Document zoQYxvv3vB5aaRV2zZokgMK1n

E. I. KREBS PIGMENTS DEPARTMENT 256 VANDERPOOL STREET NEWARK, NEW JERSEY SeftrMiaM-Nfoft. Numerical File NEWARK PLANT PIGMENT COLOR RESEARCH REPORT FILE: DATE: Serial 'KN-51*-! Copy No. Copy to: 1 - Numerical File 2 - Research File MR 210; CR 176.1 3 - Library File MR 210; CR 176.1 h - - J. N. Tully/A. Siegel 5 - W. F. SpengemanA-ibrary 6 - Extra 7 - Extra JUN 2$m4 a ft. JJi NEWARK PLANT CHEMICAL DIVISION - COLORS Progress Report EFFECT OF AA-33-D ON FLAMMABILITY OF CELLULOSE ACETATE NOVEMBER, 1953 - JUNE: 195** CHARGE: 1101-11-277 1101-11-701 J .K c SUBMITTED BY: J. JACKSON APPROVED BY: B. H. PERKIN DATE SUBMITTED: 6AO/51* DATE ISSUED: 6/22/5** DUP050069872 immgflfflit This report summarizes the current status of a problem having as its objective the development of a flame retardent for cellulose acetate rug fiber. The U. S. consumption of acetate rug fiber has been estimated (letter M* Couper - J.J. 4/2/54) as 10-15 million lbs. of fiber in 1952* and a potential of 4o million lbs. in the near future seems possible. DuPont's share of this potential market could be as high as 5 million lbs. The attainment of this objective will necessitate the development of a suitable flame retardent resistant to water washing. The trade is apparently willing to pay approximately $.02 - $.05 per pound of yarn to achieve this goal. This study was undertaken as part of a broad program on the subject of inorganic pigment modifiers for organic polymers. The related subjects have been reported on in KN Reports 53-6, #+-13, 14, 15, 17, 18, and 19. Specific references to the chemistry of AA-33-D is to be found in k n -54-18 and the corresponding DSW-53-4. Although this problem is incomplete, this Progress Report has been written at this time because the writer is being transferred to other work, SUMMARY AND. CQNCmiQM? 1. AA-33-D, a coprecipitated (Fe4(1c>207)x) (Na4P207)y(H2Q)*, when suitably dispersed within the structure of the polymer, has been found to markedly decrease the flammability of cellulose acetate either in the form of cast films or co-spun rug type fiber. 2. The pigment in its original form loses its beneficial effects upon the flammability characteristics of cellulose acetate when the cast films or rug fiber is extracted in a boiling detergent or soap solution. This gain in flammability of pigmented polymer is not shown in "dry cleaning" washes. 3. Modifications of the original pigment involving antimony (1470-28C) or titanium treatments (1470-28E) have been found to markedly improve the flammability characteristics after washing tests in which the original pigment has failed, (Memoranda D. A. Rausch - J.J. 6/7/54), 4. Co-pigmentation of cellulose acetate with AA-33-D and urea has resulted in cast films or rug fibers which are flame retardent only after water washing, i.e., the polymer develops its retardeney during a water contact and is not retardent unless subjected to this treatment DUP050069873 2 5. The effects of these pigments upon such properties of the cellulose acetate fiber as - a) physical properties b) dyeability c) lightfastness d) resistance to ,,dry,, cleaning e) resistance to repeated aqueous washing will have to be determined before a decision as to their commercial merit can be determined, 6. Studies upon the effects of Iron and antimony pyrophosphates on Orion films are of doubtful significance. The magnitude of the potential market for a flame retardent in this fiber is undetermined at this time. PATEOT STATUS A survey of the literature will be made to determine the possibility of patenting these compositions of matter for the purposes outlined in this report. A literature survey on the chemistry of iron pyrophosphate has been previously written (J.J. 1/29/54). The idea of attempting to develop flame retardency in a cellulose acetate film or fiber by means of co-spinning a pigmented yarn was discussed by A. Siegel and J. Jackson on or about 11A7/53* The broad concept that inorganic film fortifiers might he used to alter the physical properties of organic polymers had been discussed previously (Memo BHP & JFH, Oct. 23 1952). Various possibilities including that of flame retardency were discussed. The first experiment was run on 11A8, 1953 and recorded in N.B.1470-8, The results of these experiments were disclosed to B.E.Pfcrkins on 11/19/53. Contact was made with the Textile Fibers group, and first experimental samples submitted on 12/9/53 (J.J,--*-W,G. Mikell). No samples have been submitted outside the company as of this date. RECOMMENDATIONS FOR FUTURE WORK: Suitable samples of 1470-28C, 1470-28E, and AA-33- ere being prepared for submission to Textile Fibers for large scale testing. The results of these studies should be followed to determine the course of the future program. The use of the AA-33-D/urea technique is of particular interest to us, since this pigment may be of value for other applications such as a transparent film fortifier for alkyd and lacquer systems. DUP050069874  3' ** The modifications involving antimony and titanium are more highly colored and less transparent*In th writer's opinion, they would he less durable in an alkyd system. This point has not been examined, however* The possibilities of flame retardants and general film fortification effects in other polymeric systems should be determined* "Yinyon" (vinyl chloride-vinyl acetate co-polymer) and "Dynel" (vinyl chloride acrylonitrile co-polymer) are both solvent spun and should readily lend themselves to this type study. The flammability of "Dynel" is reported to be very low# The effects of transparent pigments upon the protein type polymers "Vicara" is unknown. The effects of Iron and antimony or iron-titanium combinations on cellulose might be worthy of study if they have not been considered in the work on "Erifon", REFERENCES: 1. Correspondence on this subject is filed in DSM-54-8. 2. Chemistry of AA-33- is discussed In DSN-53-1*-* 3..Effects of transparent film fortifiers on unsupported polymers -(KN-54-15) If, N.B* references - 1470 5* Monthly Summary of Inorganic Laboratory - December 1953 * July, 1954. Publications of interest in this field include 1. U.S. Department of Commerce lB-150 Biography of Reports on Flame Proofing of Textiles. 2* Literature and Patent Survey * "The Flame Proofing of Textiles" QM Research and Development Laboratories* Bibliographic Series #18. 3. Malowan Canadian Patent 499,723 Use of Water Soluble N-P. Compounds as flame retardents. 4. U.S* Patent 2,662,834, Use of bromlnated alkyl phosphate to flame retard cellulose acetate* 5. Rayon Department - Acetate Research Section - WP-123 1-14-43 Flame Proofing of Cellulose Acetate. 6. R. W. Little. Flame Proofing Textile Fabrics. ACS Monograph #104. Reinhold Pub. Co. 1947. DUP050069875 - If 7* Davis, et al. Journal of The Textile Institute ]Q T-839-854 19^9. The Urea-Phosphoric Acid Method of Flame Proofing Textiles. 8. Flame Retardants - Symposium - Church, et al. Ind. Eng. Chem. Jtg. ifl8 1950. DISCUSSION: A - Scone of Study These activities are part of a broad program on the subject of inorganic modifiers for organic polymers. (Project 701). See KN-53-6, 54-15. Most of the emphasis in this report has been placed on the evaluation of pigment possibilities for flame retardents in cellulose acetate, since early suggestions made to those working. In the Orion field did not prove to be of interest. (J.J. - W.O.Mikell 12/9/53) (Record of conversations: J.J. - W.O.Mikell 1/11/54 - 1/19/54). At the time the original samples were submitted (Dec. 1953) both the Orion group and the cellulose acetate group were working with an Orchem dichloride and dpirpohdeuncytlp(rpooplyapnheos+p$h2on./altbe.)frowmhicehthaanpeppehaoresdphtoonyol-ffer promise as a flame retardent for the materials. This product has since been abandoned by the Orion group because of detrimental effects upon the polymer (dyeability, lightfastness, etc.). (J.J. Report of visit 5/20/54 - Textile Fibers, Waynesboro, 7a.)* Work on the flammability of Orion was reported to have been dropped (Dr. W. G, Mikell) and it would appear that no emphasis be placed on this subject until the market possibilities for the application be clarified. B - Flame Retardency Mechanisms No fully satisfactory explanation of flame retardency has been advanced to date. Several hypotheses are currently in use - 1, Chemical theory - catalyzed combustion, lower exothermicity. 2, Coating theory * low melting point. Substances cover combustion site. 3. Gas theory - inert gas to smother flame. 4. Thermal theory - endothermic reaction to reduce energy source. DUP050069876 5 Chemical theory Involves concepts that the flame retardent is chemically hound to the molecule of cellulose or cellulose acetate in such a fashion as to promote the formation of reactions which are of lower exothermicity than those prevalent in their absence. Such products as strong alkalies or mineral acids such as sulfuric or phosphoric have a definite effect upon cellulose to catalyse its decomposition in the presence of heat. The ideal reaction from this point of view is (c 6h 105)x SgSi----6*c + 5X H20* instead of combustible tars and gases. C - Area - Phosphate Flame Retardenev A standard method of flame retarding cellulose involves a treatment of cellulose with a urea/phosphorlc hath treatment followed by a fusion step. Cellulose esterification is believed to take place as a result of the high temperature reactions between the Hydroxyl groups of the cellulose and the phosphoric acid or (NHw)2 EUPQl treatment in the urea/phosphoric acid flame retardency procedures, r cell - C% - 0 - P: IU d // 0 0 + The retardency is thought to result from this esterification . of the free hydroxyl groups of the cellulose molecule. The forma tion of cellulose esters makes cellulose more resistant to combus tion, Cellulose acetate is more resistant to combustion than cellulose but does contain free hydroxyl groups which can con ceivably perform in a similar fashion to those of free cellulose. It is not inconceivable, therefore, that the mechanism of flame retardency involved in these studies is the formation of a more highly esterified cellulose acetate in which the pyrophosphate ion attaches itself to the free hydroxyl groups of cellulose acetate via esterification or hydrogen bonding. The acidic nature of AA-33-& lends weight to the hypothesis that there are groups in the structure of the pigment capable of esterification. Substitution of cellulosie hydroxyl groups for water molecules in the AA-33-D is also possible. The bonds formed in the original non-aqueous dispersions of pigment and cellulose acetate may conceivably be disrupted during aqueous washing (hydrolysis of the ester). DUP050069877 -6- EXPERIMENTAL: A - TgfiftnfelMt The effects of various pigments on the flammability of cellulose acetate and Orion have been determined. The technique used in these studies has been - 1. Grind pigment 24-72 hrs, in the solvent in which the polymer is soluble. Cellulose Acetate: 15# Pigment - 8l# Acetone - Orion: 4# cellulose acetate. 15# figment - 85# dimethyl formamide. 2. Add 2-5# of dispersed pigment (dry basis) to a solution of the polymer in a suitable solvent, 3. insure good mixing of dispersed pigment and polymer by stirring one hour with air driven propeller agitators fitted with water cooled condenser covers to prevent evaporation of solvent, 4. Make ,015** or 006M (wet film thickness) draw-downs on plate glass and dry 30-45 min. at 160F to evaporate solvent, 5. Cut films into 1" x 5" strips and determine flammability with the longer dimension held vertically. Characteristics such as - a) ease of ignition b) ease of propogation or lack of propagation of flame c) relative amount of volatile combustible gases evolved d) degree of softening of polymer during burning e) tendency to after-glow in residue were determined. In the early work an attempt was made to determine the time required to burn each strip. Both the accuracy and the precision of this procedure is low and,in the absence of standard A.S.T,C.C.burning equipment, qualitative observations of the type previously indicated are probably satisfactory. Observations made in repeated tests, using a micro burner (flame from a drawn out glass tube), have been shown to correlate qualitatively with actual A.S.T.C.C. type tests on pile fabrics. The slow evaporation of acetone or DMF from within a dry film has to be considered. Occasionally improper results were experienced when tests were made on films which were apparently free of solvent, but which showed much Improved flammability characteristics after standing 24-48 hrs. (Evaporation of solvent?). DUP050069878 mm mm Cellulose Acetate burns quite vigorously giving off copious volumes of highly flammable gases. The substance melts during com bustion and the tarry mass continues to burn. The addition of of AA-33-P apparently increases the ignition temperature and reduces the amount of combustible volatile gases. The melted.tars do not appear to be self sustaining in flammability characteristics. The softening point of the pigmented cellulose acetate appears to be lower than that of the unpigmented material. Orion possesses char acteristics similar to cellulose acetate, but burns much more violently, 6, After preliminary determination of flammability In cellulose acetate, the pigmented films have been subject to a standard washing cycle consisting of a 30 minute boil in a *2% Dupanol WA solution. In this test films or fibers pigmented with products such as SW-156?, lose their retardency characteristics, i.e. they burn in a manner similar to the unpigmented polymer. This point (6) has received considerable study since a satis factory flame retardent for this application must be resistant to washing. Analysis of fibers before and after washing show that the explanation of the loss in retardency cannot be an extraction of the pigment from the fiber (N.B,1470-20). No change in the X-ray pattern of the pigment was detected as a result of incorporation into the cellulose acetate, and subsequent washing of the cast films. This loss in flame retardency during washing was found to proceed more rapidly if thin films (,006M wet) were used in place of ,017" films. Washing of the films in acidified Dupanol WA solution appears to markedly reduce the loss In flame, retardency ordinarily'experienced in the Dupanol or soap and water wash. (N.B.1470-233 The suggestion made by G. Seidel that washing in N8L0H containing solutions might benefit the system was tested and round to be ineffective, (N.B, 1470-30). It Is Interesting to note that AA-33-B dispersions made with acetone-water mixtures are inferior in flame retardency to a similar composition dispersed in acetone. (N.B. 1470-26). B - Modifications of M-33-D1. Since the major deficiency of the original pigment tested (AA-33-D - SW-1567, 1570) appears to be its loss in flame retardency effects after washing, emphasis has been placed on attempts to modify this pigment rather than seek entirely new pigment possibilities. This product also has possible utility as a colorless, transparent film fortifier for alkyd and lacquer samples. See KN~53~6, KN-54-18. DUP050069879 -8- 2. Variables studied* Reference ____JiMMfoflll 1, 1470-12 2. 1470-22 Vary Fe/Na ratio in precipitate. Treat precipitate with metal salts to.. M reduce sodium content Fe+3, Pb*12, Ca'tz, Mn ^ 3 1470-23 Make pigment surface hydrophobic instead of hydrophilic Used "Hyponate" petroleum sulfonate Naphthenic acid "Arquad S" cationic agent Silicone SC-50 (sodium methyl siliconste G.E.) 4. 1470-25 Dehydration of the AA-33-D prior to acetone grind* 5. 1470-28,36 Coprecipitation of Fe/Sb, Fe/Al pyrophosphate* Filming with Al, Sb, Ti compounds* 6. 1470-29 Filming with Fe, and Pb salts of carboxy methyl cellulose. Precipitation with K^HPgOy in place of Na^PgOy 7* 1470-37 a. 1470-38 9. 1470-39 Copigmentation with AA-33-D and urea Copigmentation with AA-33** and Carbopul 934 AA-33-D and Urea-formaldehyde Filming with urea-formaldehyde. 10* 1470-42 Copigmentation with water insoluble, solvent soluble urea formaldehyde resin Aerotex P-200. The results of these studies in cellulose acetate are tabulated in Table l,and in Orion in Table II. As can be seen from Table I, the products of particular interest at this time are 1470-28C - .8 mol Fe/.2 mol Sb pyrophosphate (?) and 1470-28E - Feu.(p2?H filmed with TiOp (?) The exact chemical compo sition of these products is unknown. These products were designed on the assumption that (1) metallic combinations might give better results than those from a single metal (similar to Erifon studies). (2) filming of the AA-33-D particle might affect its water sensitivity. These combinations have not been exhaustively studied and it is entirely possible that some other Fe/Sb or Fe/Tl, or possibly Fe/Sb/Ti combination, might give even superior results. DU P050069880 9 The urea/M-33-D copigmentation work is also extremely interesting and should he pursued further. This makes use of the AA-33-D in its original form, which would probably he more useful in other pigment applications than the Sb and Ti treated variations The published work on the urea-phosphoric treatment of cellulose was of value in this phase of the study (Davis, et al J. Textile Inst. \T-839 1949) (little - Flame Proofing of Textile Fabrics. ACS Monograph IOh- Reinhold Pub. 1947), and offers a possible explanation of the mechanism of phosphate type flame retardents. C Other Studies on Flammabllitv 1. Alkyd Resin A dispersion of AA-33-D - SW-1567 at P/B = .19 in a Syntax 26/Resimene 881 system was compared in flammability char acteristics with a clear of the same vehicle. Films of .015 wet film thickness were made on glass plates and subsequently baked and stripped. The inclusion of AA-33-D had a beneficial retarding effect on the rate of combustion of these strips. (N.B.1470-11). The use of AA-33-D in a casein brushout formulation applied to the surface of paper stock had some beneficial effect on the rate of combustion of the paper. Attempts to incorporate the pigment within paper stock by a beater dyeing procedure gave no improvement in flammability characteristics. (N.B.1470-35). . 3 Viscose AA-33-D as such is decomposed by the highly alkaline solutions encountered in this field. The pigment in its present form would be unsatisfactory since it could not be Incorporated into the fibers by co-spinning. 4-V-tnvl A sample of AA-33-D (1567) has been submitted to Newburgh (F<&F) for evaluation of possible flame retardency In vinyl films. (R.H.Z. - Luaena 4/6/54, 4/8/54). DUP050069881 -- 10 *> mi EXPERIMENTAL RESULTS OBTAINED CELLULOSE ACETATE STUDIES - CAST FILMS ElfiffigSk Lot Amount Reference Effect on Flammability AA-22-D 1499 AA-33-D SW-1567/ 14?0 2% 2% 1470-8 1470-8 slight retardency Retardent - effect lost on washing. AA-33-D Variation in Na/Fe 2$f 1470-12 Retardent mm effect lost on washing AA-33-D Treated with Fe+3 it Caj tt M Pb*^2 ii it Mn*^ it " Hyponate h% 4# h% h% 147n0-22 n ti 1470-23 Retardit ent mm MB efiftect lon st on n wasnhing tt m n n tt tt ti tt m v.sl.better than aa-33' - lost on washing it " Naphthenic Acid *t it ** "Arquad 8" hi it it mm n ti tt .mm f ti it ti w n ii " Silicone SC-50 it n dehydration pH variations ii co pptd Fe/Sh it Fe/Al it Film with A1 it Sh ti it it Ti ti it n FeCMC ti i phCMC Use K to eliminate Na w h% hi h% hi h% h% hi hi hi 4# n 1470-25 1470-24 1470-28* tt it ii n 1470-29 it it ii m* it n n tt it ii tt i? tt tt 'mrn n ii ii tt tt it n ti it M - much better hi, --. v.sl. " - si. " - si. " thtian it tt AiAi -33 tt it n lo st on ii wasnhing tt II tt n n it AA-33-D Co-spin with Urea h% AA-33-D 11+70-37 Not 2% Urea retardent - Retardent after washing n Co-spun ^arhojpul 4# Co-spin UreaFormaldehyde h% w Film with UreaFormaldehyde h% " Co-spin AA-33-D hi Aerotex 2i P-200 1470-38 it 1470-39 1470-42 slight retardent - lost on washing not not retardent retardent - after washing slight retardent Retardent - after washing Not " Not retardent after washing See also 1470-36 DUP050069882 11 TABLE I (Coat'd.) Pigment Lot Amount S.eferen.ee Effect on Flammability GI-734-D SW-1709 AA-34-D 1690 2% Tetrachlor phthallc anhydride 2% Tetrachlor phthalind.de 2% Mn5(P3010)3 1376~28B H Cpe3CPPl|.>a 1376-18A 4# Fe2p27 1376-18B 4# 5/6 PeU(P207)3 1^15-77A 4# 1/6 Fe(0H)3 1470-8 11+70-8 1470-11 1470-11 1470-23 1470-23 1470-23 1470-23 ineffeI! ctive It H II II Not as good as AA-33-D. Effect lost on washing. + *= AA-33-D Effect lost on washing. 2/3 Feif(P207>3 1415-77B 1/3 Fe(0H)3 PePO^ 1470-24 4$ Fe5(P3010)3 11+70-24 M62P27 1415-6 4$ sto2p27- 1470-130 4jg Tl(OH)^ 1376-54A 4{g & 54b 1376-14 4jg 1470-23 1470-24 1470-24 1470-31 1470-44 1470-44 1470-44 Urea 4jg 1470-44 + * AA-33-D Effect lost on washing. + ** aa-33-0 Effect lost on washing. + * AA-33-D Effect lost on washing, slightly retardent. Effect lost on washing. Not retardent Not retardent aftfr washing, Retardent Effect loat on washing. Not retardant Not retardent after washing. Not retardent Not retardent after washing. DUP050069883 * '<4 -12 %m&M OHLON STUDIES - CAST FILMS Pigment L2i .Amount Reference AA-22-D AA-33-D 1499 3# 1567 3# m 1470-9 1470-9 GI-734-B 1576 AA-34-P 1690 Basic Alum. Sulfate 1446-29 A--I--I) Sb^(P207)^ 1376-86D % 3$ 3$ 3f 3$ Tetrachlor phthallc anhydride 3% 50/50 #2 & #8 3i 50/50 #7 & #8 3f 50/50 #2 & #7 3% Sbi^CPaOy^ various 3% compositions m 1858** 3-6# 1470-9 3470-9 1470-9 1470-9 1470-9 1470-9 1470-9 1470-9 l4709 1470-13 1470-12 Effect on Flammability Ineffective *** Slightly lessflammable* Mot as good as 3f * Ineffective Ineffective * * Ineffective * Ineffective * Beneficial - less flammable* v.sl. less flammable Mot different from AA-33-P. Hot different from Sb^CPgOy)^ Inferior to #7 Less flammable than control si.less flammable than control * No change in results when films washed 30 min. .2# Dupanol WA. at 212F ** Product supplied by Orchem-Polyphosphonate from ethane-phosphonyl dichloride and diphenylol propane. DUP050069884 Serial KN-5^-16 Copy Ho. l Copy toi 1a - Numerical File Research File MR 210) CR 176.1 I - Library pile MR 210) CR 176.1 V - J. R. fully/A. Siegel 5 * W. F. SpengemanAibrary 6 Extra 7 Extra HBWAHK PLANT CHEMICAL DIVISION * COLORS Progress Report EFFECT OF AA-33-B ON FLAMMABILITY OF CELLULOSE ACETATE NOVEMBER, 1953 * JUNE, 195** CHARGE* 1101-11-277 1101-11-701 SUBMITTED W/Z. Z. APPROVED BY* DATE SUBMITTED* 6/10/5** DATE ISSUED: 6/22/5** DUP050069885 This report summarizes the current status of a problem toying as its objective the development of a flame retardent for cellulose acetate rug fiber. The 0. 8. consumption of acetate rug fiber has been estimated (letter M. Couper - J.J. 4/2/54) as 10*15 million ibsu. of fiber in 1952, and a potential of Vo million lbe. in the neair f_uture s.. ee. ms possible* DuPont's share of this potential market coutld be as high as 5 million lbs. The attainment of this objective will necessitate the development of a suitable fli re resistant to water washing. The trade is apparently willing to pay approximately $.02 $*05 per pound of yam to achieve this goal* This study was undertaken as part of a broad program on the subject of inorganic pigment modifiers for organic polymers. The related subjects have been reported on in SI? Reports 53-6* 54-13, 14, 15, 17, 18, and 19* Specif!c references to the chemistry of AA-33-D is to be found in m-54-18 and the corresponding PSM-53*** Although this problem is incomplete, this Progress Report has been written at this time because the writer is being transferred to other work* mjzmmim* 1. M-33-D, a coprecipitated (Fe4(P207)x) (!?a4^207)y<%G)|, when suitably dispersed within the structure of the polymer, has been found to markedly decrease the flammability of cellulose acetate either in the form of oast films or eo-spun rug type fiber. 2. The pigment In its original form loses its beneficial effects upon the flammability characteristics of cellulose acetate when the cast films or rug fiber is extracted in a boiling detergent or soap solution* This gain in flammability of pigmented polymer is not shown in "dry cleaning" washes. 3. Modifications of the original pigment involving (1470-28C) or titanium treatments (1470*282) have been found to markedly the flammability characteristics after washing tests in which the original pigment has failed. (Memoranda D* A. Rausch - 0.J. 6/7/54). 4. Co-pigmentation of cellulose acetate with AA-33-D end urea has resulted in oast films or rug fibers which are flams retarding only after water washing, le., the polymer develop# its retarded* during a water contact and is not retardent unless subjected to treatment. DUP050069886 -2 - 5. file effects of these pigments upon such properties of the cellulose acetate fiber as - physical properties disability lightfastnesa resistance to "dry" cleaning resistance to repeated aqueous Hashing Hill have to be determined before a decision as to their commercial merit can be determined* 6* Studies upon the effects of iron and antimony pyrophosphates on Orion films are of doubtful significance, fhe magnitude of the potential market for a flame retardent in this fiber is undetermined at this time* nfiXjiSEffftii. A survey of the literature will be made to determine the possibility of patenting these compositions of matter for the purposes outlined in this report* A literature survey on the chemistry of iron pyrophosphate has been previously written (J.J. 1/29/5V). The idea of attempting to develop flame retardency in a cellulose acetate film or fiber by means of co-spinning a pigmented yarn was discussed by A* Siegel and J. Jackson on or about 11/17/53. The broad concept that inorganic film fortifiers might be used to alter the physical properties of organic polymers had been discussed previously (Memo BHP & JFH, Oct. 23*1952). Various possibilities including that of flame retardency were discussed* The first experiment was run on 11/18, 1953, and recorded in H.B.1470-8. The results of these experiments were disclosed to B.H.Perkins on 11/19/53. Contact was made with the Textile Fibers group, and first experimental samples submitted on 12/9/53 (J.J. W.O. Mlkell). Mo samples have been submitted outside the company as of this date. Suitable samples of 1470-280, 1470-28B* and AA-33-D ere being prepared for submission to Textile Fibers for large scale testing* The results of these studies should be followed to determine the course of the future program. The use of the AA-33-D/urea technique is of particular interest to us* since this pigment may be of value for other applications such as a transparent film fortifier for alkyd and lacquer systems. DUP050069887 3 The modifications involving antimony and titanium are more highly colored and less transparent,In the writer's opinion, they would he less durable in an alfcyd system. This point has not been examined, however. The possibilities of flame retardants and general film fortification effects in other polymeric systems should be determined. "Finyorn" (vinyl chloride-vinyl acetate co-polymer) and "Dynel" (vinyl chloride acrylonitrile co-polymer) are both solvent spun and should readily, lend themselves to this type study. The flammability of "Bynel is reported to be very low* The effects of transparent pigments upon the protein type polymers "Vicara" is unknown. The effects of iron and antimony or iron-titanium combinations on cellulose might be worthy of study if they have not been considered in the work on "Erifon". > REFERENCES! 1. Correspondence on this subject is filed in DSN-54-8. 2* Chemistry of AA-33-D is discussed in DSN-53-*-. 3, Effects of transparent film fortifiers on unsupported polymers --(KN-54-15). 4, N.B. references - 14-70 5, Monthly Summary of Inorganic laboratory December 1953 - July, 1954* Publications of interest in this field include - .1* U.S. Department of Commerce IB-150 Biography of Reports on Flame Proofing of Textiles* 2. Literature and Patent Survey - "The flame Proofing of Textiles" ^01 Research and Development Laboratories. Bibliographic Series #18. 3* Malowan Canadian Patent 4-99,723 Use of Water Soluble H-P. Compounds as flame retardants. 4-. U.S* Patent 2.662,834-., Use of brominated alkyl phosphate to flame retard cellulose acetate* 5* Rayon Department - Acetate Research Section - WP-123 1-14-4*3 Flame Proofing of Cellulose Acetate* * 6* R, W. Little. Flame .Proofing. Textile Fabrics. ACS Monograph #104-. Reinhold pub. Co. . DUP050069S8S 7* Davia, et al. 4J0ournal of The jTtietfOxt,ile Institute The Grea-Phospnorio Acid Method of Flame Proofing Textiles* 8. Flame Retardants - Symposium - Church, et al* Xnd. Eng. Cham. 418 1950* vzmmmi A - ftBfiM-PJLStiito These activities are part of a broad program on the subject of inorganic modifiers for organic polymers* (Project 701)* See Klf-53-6, 54-15* Most of the emphasis in this report has been placed on the evaluation of pigment possibilities for flams retardants in cellulose acetate* since early suggestions made to those working lathe Orion field did not prove to be of interest* (J.J. - W.G.mkell 12/9/53) (Record of conversations* J.J. - W.G.Mikell 1/11/54 - 1/19/54). At the time the original samples ware submitted (Dec. 1953) both the Orion group and the cellulose acetate group were working with an Orchem product (polyphosphonate from ethanephosphonyldichloride and dlphenylpropane $2. Ab.) which appears to offer promise as a flame retardent for the materials. This product has since been abandoned by the Orion group because of detrimental effects upon the polymer (dyeability. lightfastness, etc.). (J.J. Report of visit 5/20/54 - Textile Fibers, Waynesboro, Va*). Work on the flammability of Orion was reported to have been dropped (Dr*>W. G* Mikell) and it would appear that no emphasis be placed on this subject until the market possibilities for the application be clarified. b - fima.^,^J^cxJapMaiga8. No fully satisfactory explanation of flame retardency has been advanced to date. Several hypotheses are currently in use - 1. Chemical theory - catalysed combustion, lower exothermiclty. 2. Coating theory - low malting point. Substances cover eombusticii tite# 3. Gas theory - inert gas to smother flame* 4* Thermal theory - endothermic reaction to reduce energy source. DUP050069889 -5 Chand.cal theory involves concepts that the flame retardent is chemically hound to the molecule of cellulose or cellulose acetate in such a fashion as to promote the formation of reactions which are of lower exothermicity than those prevalent in their absence* Such products as strong alkalies or Mnsral adds such as sulfuric or phosphoric have a definite effect upon cellulose to catalyse its decomposition in the presence of heat* The ideal reaction from this point of view is <c#LO%>x 2^---- %3 + 9* %0* v instead of combustible tars and gases* C A standard method of flame retarding cellulose Involves a treatment of cellulose with a urea/phosphoric bath treatment followed by a fusion step* Cellulose esterification Is believed to take place as a result of the high temperature reactions between the Hydroxyl groups of the cellulose and the phosphoric add or (NEUo treatment in the urea/phosphoric add flame retardency procedures* + ch2 the retardency is thought to result from this ssterlfioation of idle free hydroxyl groups of the cellulose molecule* The forma* tion of cellulose esters makes cellulose more resistant to combus tion* Cellulose acetate is more resistant to combustion than cellulose hut does contain free hydroxyl groups which can con ceivably perform in a similar fashion to those of free cellulose* It is not inconceivable, therefore, that the mechanism of flams retardency involved In these studies is the formation of a more highly esterified cellulose acetate in which the pyrophosphate ion attaches itself to the free hydroxyl groups of cellulose acetate via esterification or hydrogen bonding. The acidic nature of AA-33-D lends weight to the hypothesis that there are groups in Mis structure of the pigment capable of esterification. Substitution of cellulosic hydroxyl groups for watsr moleculss in the AA-33-I5 Is also possible. The bonds formed in the original non-aqueous dispersions of pigment and cellulose acetate may conceivably be disrupted during aqueous washing (hydrolysis of the ester)* DUP050069890 6 A - Technique The effects of various pigments on the flammability of cellulose acetate and Orion have been determined. The technique used In these studies has been - 1. Grind pigment 24-72 hrs. in the solvent in which the polymer is soluble. Cellulose Acetatei 15% Pigment - 61$ Acetone - cellulose acetate, Orion: l$% Pigment - &5$ dimethyl formaaide. 2. Add 2-50 of dispersed pigment (dry basis) to a solution of the polymer in a suitable solvent, 3. Insure good mixing of dispersed pigment and polymer by stirring one hour with air driven propeller agitators fitted with water cooled condenser covers to prevent evaporation of solvent. 4. Hake ,015" or .006" (wet film thickness) draw-downs on plate glass and dry 30-45 min, at l6oF to evaporate solvent* 5* Cut films into 1" x 5" strips and determine flammability with the longer dimension held vertically* Characteristics such as - a) ease of Ignition b) ease of propagation or lack of propogation of flame c) relative amount of volatile combustible gase: evolved d) degree of softening of polymer during burning e) tendency to after-glow in residue s ? were determined* In the early work an attempt was mads to determine the time required to burn each strip* Both the accuracy end the precision of this procedure is low and,In the absence of standard AwSkT,Ci?Uwrning equipment, qualitative observations of the type previously indicated are probably satisfactory. Observations made in repeated tests, using a micro burner (flame from a drawn out glass tube), have been shown to correlate qualitatively with actual A.S.T.C.C. type tests on pile fabrics. The slow evaporation of acetone or BMP from within a dry film has to be considered. Occasionally improper results were experienced when tests were made on films which were apparently free of solvent, but which showed much improved flammability characteristics after standing 24~h8 hrs. (Evaporation of solvent?). DUP050069891 -7- Cellulose Acetate turns quite vigorously giving off copious volumes of highly flammable gases* The substance melts during com* bustion and the tarry mass continues to burn* The addition of 2$-5% of AA-33-D apparently Increases the ignition temperature and reduces the amount of combustible volatile gases. The melted tars do not appear to be self sustaining in flammability charactorieties. The softening point of the pigmented cellulose acetate appears to be lower than that of the unplgmented material. Orion possesses char* acteristlca similar to cellulose acetate, but burns much sure violently. 6. After preliminary determination of flammability in cellulose acetate, the pigmented films have been subject to a standard washing cycle consisting of a 30 minute boll in a .2# Dupanol WA solution. In this test films or fibers pigmented with products such as 3W-1567, lose their retardency characteristics, i.e, they burn in a manner similar to the unplgmented polymer. This point (6) has received considerable study since a satis factory flame retardent for this application must be resistant to washing* Analysis of fibers before and after washing show that the explanation of the loss in retardency cannot be an extraction of the pigment from the fiber (N.B.1470-20). Ho change in the X-ray pattern of the pigment ms detected as a result of incorporation into the cellulose acetate, and subsequent washing of the cast films. This loss in flame retardency during washing was found to proceed more rapidly if thin films (.006" wet) were used in place of .015" films. Washing of the films in acidified Dupanol WA solution appears to markedly reduce the loss in flame retardency ordinarily experienced in the Dupanol or soap and water wash. (N.B.1470-23) The suggestion made by o. Seidel that washing in NHkOH containing solutions might benefit the system was tested and round to be Ineffective. (N.B. 1470-30). It is interesting to note that AA-33-D dispersions made with acetone-water mixtures are inferior in flame retardency to a similar composition dispersed in acetone* (H.B. 1470-26). B - ,lftO&s3irBU 1. Since the major deficiency of the original pigment tested (AA-33-D - SW-1567, 1570) appears to be its loss in flame retardency effects after washing, emphasis has been placed on attempts to modify this pigment rather than seek entirely new pigment possibilities. This product also has possible utility as a colorless, transparent film fortifier for alkyd and lacquer samples. See KH-53-6, KH-54-18. DUP050069892 -8. 2* Variables studied* ,1* 1470.12 2 1470-22 Vary Fe/Ha ratio la precipitate. treat precipitate with metal salts to^ ,, 4 reduce sodium content Fe+3, Pb*8, Ca*2, l|Bp* 3. 1470-23 Make pigment Surface hydrophobic instead of hydrophilic. Used "fiyponate" petroleum sulfonate Naphthenic acid "Arquad S" cationic agent Silicone SC-50 (sodium methyl siliconete G.E.) * 4. 1470-25 Dehydration of the AA-33-D prior to acetone grind* 5. 1470-28,36 Coprecipitation of Fe/Sb, Fe/Al pyrophosphate. Filming with Al, Sb, T1 compounds* 6. 1470-29 Filming with Fe, and Fb salts of carboxy methyl cellulose. Precipitation with K^HPgOy in place of N%%0^ .7# 1470-37 8 1470-38 9* 1470-39 Copigmentation with AA-33-D and urea Copigmentation with AA-33-D and Carbopul 934 AA-33-D and Urea-formaldehyde Filming with urea-formaldehyde* 10* 1470-42 Copigmentation with water insoluble, solvent soluble urea formaldehyde resin Aerotex P-200* The results of these studies in cellulose acetate are tabulated in Table I,and in Orion in Table XX. As can be seen from Table X, the products of particular interest at this time are 1470-28C - .8 mol Fe/*2 mol Sb pyrophosphate (?) and 1470-288 - Fe4(p207>3 filmed with TiOz (?). The exact chemical compo sition of these products is unknown. These products were designed on the assumption that (1) metallic combinations might give better results than those from a single metal (similar to Brifon studies). (2) filming of the AA-33-D particle might affect its water sensitivity. These combinations have not been exhaustively studied end it is entirely possible that, some other Fe/Sb or Fe/Ei, or possibly Fe/Sb/Tl combination, might give even superior results* DUP050069893 9 The urea/AA-33-D copigmentation work is also extremely interesting and should he pursued further. This makes use of the AA-33-D in its original form, which would probably he more useful in other pigment applications than the Sb and Ti treated variations. The published work on the urea-phosphoric treatment of cellulose was of value in thist phase of the study (Davis, et si J. Textile Inst. 1+0 T-839 1949) (Little - Flame Proofing of Textile Fabrics. ADS Monograph 104 Reinhold Puh. 194-7) and offers a possible explanation of the mechanism of phosphate type flame retardents. c. othw. ffMLgg. i. Atol-Mflln A dispersion of AA-33-D - SW-1567 at P/B .15 in a Syntex 26/Resimene 88l system was compared in flammability char acteristics with a clear of the same vehicle. Films of .015 wet film thickness were made on glass plates and subsequently baked and stripped. The inclusion of AA-33-D had a beneficial retarding effect on the rate of combustion of these strips. (N.B.14-70-11). 2. Parer The use of AA-33-D in a casein brushout formulation applied to the surface of paper stock had some beneficial effect on the rate of combustion of the paper. Attempts to incorporate the pigment within paper stock by a beater dyeing procedure gave no improvement in flammability characteristics. (N.B.14-70-35). 3* Viscose / AA-33-D as such is decomposed hy the highly alkaline solutions encountered in this field. The pigment in its present form would be unsatisfactory since it could not be incorporated into the fibers by co-spinning. h * ^sample of AA-33-D (1567) has been submitted to Newburgh (F&F) for evaluation of possible flame retardency in vinyl films. (R.B.Z. - Luzena 4-76/54-, 4-/S/54-). DUP050069894 10 - TABLE 1 EUPERIMmffAL RE3ULT8 OBTAINED CEU.BI.08B ACETATE STUDIES -CAST FILMS iai Aasani Bs&caasa Effect on M-22-D AA-33-D SW-1567/ % 1470*8 14-70*8 slight retardency Retardent * effect lost oh washing. AA-33-D Variation ih Sl/P 2$ 1470-12 Betardent - effect lost on washing AA-33-D Treated with, MiB B Ca* H 1470-22 B BetardH ent effect lost on washing B B8 tt ;>;g- M II B B BB B fl B Mn*2 4$ II v.si.better than AA-33-0 B B Hyponate 4* 1470-23 B lost on washing B II Haphthenic H Add 4* tl "Arquad SM 4? B ft n B II B I B If B B B B Silicone II B SC-50 dehydration pH variations B 8 II oo pptd Po/Sh Pe/Al Film with A1 tl BB gfc tt it B ijjjt B b it FeCMC B b PbCMC Use K to eliminate Ha 4* Mi MM4M?iii % 4M?i 1470-25 1470-24 1470-28* 8 It 1470-29 B It It B II B 8B B It B B II 8 B II B much better than AA-33-0 1. M " B B v.al. si. w B B si. " " lo8 st 8on wasBhing "II II B -B B AA-33-D Co-spin with Urea 4* AA-33-D 1470-37 Hot 2% urea retardent * Retardent 'after washing " Co-spun ^arbojpul slight 4j{ 1470-38 retardent - lost on washing ** Co-spin Urea* not not retardant Formaldehyde 4jf " retardent - after washing film with Urea* slight retardent Formaldehyde 4# 1470-39 Betardent - after " Co-spin AA-33-U 4i 1470-42 not * Jerotex . 2% P-200 - Not retardent after washing .f f *See also 1470-36 DUP050069895 - 11 TABLE 1 (Cont'd*) Pigment hS& ilBMft flflfffl.lMl QI-734-D SW-1709 AA-34-D 1690 Tetrachlor phthalie anhydride Tetrachlor phthalimlde Mn5(p3io)3 1376*288 F3<P04>2 1376-18A 2* 23C 2< 2% 4* 4^ 1470-8 1470-8 1470-11 1470-11 1470-23 1470-23 P2p27 1376-18B 436 1470-23 5/6 Fd4(I07)3 1415-771 4* 1470-23 1/6 FTo H)3 .jsfto.s ?n nummm IneffeM ctive R n 11 N Not as good as AA-33-D. Effect lost on washing* + AA-33-D Erfsot lost on washing* 2/3 F4(Ifc07)3 1415-77B 4* 1/3 F(0H>3 FePO^ 1470-24 4^ 1470-23 1470-24 Fa5(P3Oio>3 M^2P27 SlfelfeOp 1470-24 4* 1415-6 4JC 1470-13C 4jf 1470-24 1470-31 1470-44 Tl2Pfc07 T1(0H)4 1376-54A 4* ft 548 1376*14 4* 1470-44 1470-44 Urea 4* 1470-44 * AA-33-D Rffsct lost on washing* + AA-33-D Effect lost on washing* m AA-33-D sffact lost on washing* slightly retardent. Not retardant aftar washing. Retardant Effect lost on washing. Not retardant Not retardent after washing. Not retardent Not retardent after washing. DU P050069896 12 *PABLE II m imm.sJtWJDBun,-- Pigment AA-22-D AA-33-D Lot Amount Reference l4f9 1567 | 1470-9 1470-9 GI-734-D 1576 AA-34-D 1690 Basic Alum. , Sulfate 1446-29 A-I-D Sblf(P207)3 1376-86D & 3i 3* 3$ Tetrachlor phthalic anhydride 3# 50/50 #2 d #8 50/50 & #8 3$ 3$ 50/50 m & #7 Skf(P27)3 various compositions m 1858** 3* 3$ 3-6# 1470-9 1470-9 1470-9 1470-9 1470-9 1470-9 1470-9 1470-9 1470-9 1470-13 1470-12 Ineffective Slightly Ices Not as good as Ineffective Ineffective * * Ineffective Ineffective * Beneficial - less flammable* v.sl. less flammable Not different from AA-33-D. Not different froa Inferior to #7 Less flammable than control si.less flammable than control * h o change in results when films washed 30 min^ .2# Dupanol WA. ** dpricohdulocrtidseup&p&lieddlpbhyeOnryclhoelmp-rPooplaynpeh*osphonate from ethane-phosphonyl DUP050069897