Document 4vZBDoxmBo35Nx7p2L7O4Zqq1

E. I. DU PONT RE NEMOURS & CO. ,,, .#3 CO: A, A. Brizzolara R, F. White E. A. Stefancsik R. A. Johnson G. Grimm T. S. Pile R. A. HAGEMAN Technical Supervisor Pigments - Newark ^ Newark, New jersey ' September 15, 1964 Date Submitted: 8/1/64 DESOTO1S 5898 * HOT TINT COMPATIBILITY The following data and speculations are based on the writer*s examination of Dow and Rohm & Haas literature on acrylic emulsion paints. It is quite apparent that methocel is widely used as a viscosity control agent, and that it could be the major cause of our difficulties with "Hot" tint compatibility. R. Pascal has reported that RW-768-P was successfully used at DeSoto when the formulation was changed from methyl cel lulose to hydroxyethyl cellulose, a more water soluble type. Pascal has also reported that three systems (DeSoto*s, Dow1s 2647 and Rohm & Haas * Rhoplex AC-34) containing methyl cellulose all show hot tint sensitivity. To definitely pin this point down, I have requested an experimental emulsion from DeSoto without methocel for test. If we could obtain this, a rigorous understanding of the problem would be at hand. A discussion of this general matter of emulsion formu lation with P & F would be of considerable help. It is my under standing that they do not use methyl cellulose, it would be interesting to know why not. // V JJjdm Attachment /. j Ja c k s o n ^7 Senior Research Chemist Technical Section N39901 PROM METHOCEL - DOW CHEMICAL LITERATURE Chemistry: 1. polymer methyl cellulose CH2-OCH3 H OCH3 made from cellulose + NaQH + methyl chloride; also H I O-CH2-C-CH3 substitution available propylene glycol ether of cellulose OH 2. Vary in number substituted OH groups which determine solubility - viscosity, etc. Solution! Methocel is a nonionic hydrophilic polymer which forms aqueous dispersion by swelling and successive hydration of structural layers. No distinct solubility limit occurs. The degree of hydration is adversely effected by temperature. This dehydration lowers the viscosity level of a given methocel suspension i.e., viscosity drops with increase in temperature, Direct cold water dispersibility of methocel products is assisted by the addition of approximately 2% (based on methocel) of wetting agents such as Witco's #912 and Dowfax 9N10. Thermal Gelation: Thermal gelation is one of the unique properties of methocel i.e,, the tendency of the methocel in dispersion to gel on heating (result of dehydration of the outer layers of polymer). Tests made on DeSoto's #2898 whitebase indicate that its viscosity is lowered substantially by heating it to 120P. DUP050053756 DISPERSION m ii (Swelled structure separated by water. Hj>0 acts as lubricant) B20 H20 H20 HgO H2O Dehydration results in lack of lubrioation between layers and subsequent gelation. The addition of salts and other additives depresses the thermal gel temperature. Effectiveness is a function of valency, high valence being more effective. The gelation phenomenon is thermally reversible on cooling. Addition of ethanol or propylene glycol raises the gel ation temperature, Armac? Armac HDTf Hyamine 1622, urea also reported to raise the gelation temperature ADDITIVES Methocel is a nonionic and, therefore, not precipitated by metal ions.* * Dow's pamphlet is in error here, since these, are not correct designations for Armour's Armac series of products. DUP050053757 ill * Dow recommends the following defoamers: a. Foaraiclde 581B - Colloids, Inc. b. Antifoam A, AF, B, 0, - Dow c. Nopco KPS d. Nopco NXZ e. ,, Lauryl alcohol, tri-n-butylphosphate, poly glycol 1200, 2000. f. Latex paint system - Nopco NDW ,/g. Polyvinyl acetate - Nopco 1497 h Acrylic systems - Nopco JMK i. Styrene Butadiene - Nopco JMK j| 2$ - 1000 PPM (solution weight basis) VISCOSITY STABILITY 1. Numerous agents added to Methocel dispersion have anomalous effects on the viscosity. Monobutyl phenyl phenol Incxgaas + 60# sodium monosulfonates Robert's Chemical Company 100; i4o$ 4500$ 14000$ Dowicide B] F G Chemical 8$ 400$ 58000 pH range 3-11 has little effect on viscosity stability in storage. Solutions in strong acid or alkali will show decreased viscosity on storage. METHOCEL - UTILITY IN LATEX AND EMULSION PAINTS In addition to viscosity control, methocel, addition to various latex and emulsion paints results in1 2 3 1. better package stability 2. better application properties (thixotropy effects) 3. good color and wash resistant characteristics Methocel 65HG and 90HG types are widely used. The writer is speculating that the weak tints resulting from the "Hot" tinting of DeSoto's #2898 and other systems may be due to some temperature reversible phenomena such as the gelation referred to in the previous section which results in lowered vis cosity and possibly decreased dispersion of the blue concentrate. This may be further complicated by the specific interactions of the surfactants, and other components of the blue or green disper sion on the methocel dispersion. * DUP050053758 - iv - The function of the very high amount of surfactants found in the Hilton-Davis products may be two-fold: (a) a portion to obtain a good color dispersion; (b) a portion to keep the methocel containing White base undisturbed (not gelled etc.) on addition of the color concentrate. Our experience to date with Witco1 s #912 seems to bear this out since it is known that this agent aids in the dlsolution of methoeel. Other materials such as Dowicide G, Propylen Glycols etc., which are known to raise the gelation point of methocel will /7V'^ be tested. DOW >8 ACHYLIC EMULSION SYSTEMS - GENERAL AGENTS USED Dow's recommendations includes AGENT PROBABLE FUNCTION ethylene glycol. Poly glycol 1200 defoamer Dowfax 9N10, 9N9 Methocel 65-HG V Hydroxyethyl cellulose)cpc. Colloid 70TPS, Nopco 1497, Nopco NXZ defoamers PMO-30 Potassium Tripolyprhosphate Tam 01 731 t Daxad 30 nonionic wetting agent Emcol 5138 wetter for Methocel? wetter for methocel. Pigment. thickener thickener (Colldld Inc,Nopco Chemical) Preservative (Troy Chemical). Pigment dispersant Pigment dispersant Pigment dispersant Witco? Usual pH 8.5-9.0 Problems of color acceptance are referred to. Additional wetting agents (alkanolamine condensates, alkyl phenyl-ethylene oxide condensates) are recommended, BHOPLEX ACRYLIC EMULSIONS - GENERAL AGENTS USED Rohm and Haas literature refers to the use of: AGENTS PROBABLE FUNCTION Hydroxyoctyl cellulose Methyl cellulose Tamol 731 Triton CF10 Tamol 850 Balab 748, Nopco 1497, Nopco NXZ Ethylene glycol: pH 9.0 thickeners. Pigment Dispersant Pigment Dispersant Pigment Dispersant Antifoams . (Methocel Dispersant?) defoamer. DUP050053759 VI. AQUEOUS DISPERSIONS REFERENCE #6 A. BW-4-31-P - Role of Structure of Surfactants (JJ) The role of the structure of surfactant and quantitiy used on the dispersion of BT-352-P has received considerable attention. An accelerated making procedure based on the use of a Jiffy-Mill has been developed and gives fairly reproducible results. Evaluation Table I lists some of the tests made and results achieved in casein brushout. Siponio E15 and Pluronic F68 are superior to Renex 20, our presently used agent in this application. Examination of these dispersions in DeSoto1s acrylic emul sion system indicated that the strength advantages noted in casein are carried through (See Table II). However, all of these pigment dispersions fail the so called "Hot Tint" test (weaker when tinted at 120F. then when tinted at 8oF.) . The phenomenon appears to involve a flocculation of the blue since it can be "rubbed up" to standard strength. In most cases this is a reversible phenomenon i.e. the weak tint comes back to standard strength on cooling. The basic cause of this situation seems to involve the Methocel used as a viscosity controlling agent in the DeSoto system. We are trying to prove this by requesting Methocel-free vehicle from the manufacturer. The addition of Witco #912, a proprietary mixture of anionic and nonlonlc type agents, to either a Renex or Siponio E15 system, reduces the hot tint sensitivity. The use of this agent, to assist methocel solution,is known to the trade. Dispersions using mixtures of Slponie E15 and Witco #912 show decreased levels of foam, good hot tint dispersibility but lower strength levels than desired. This approach is receiving further attention. 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X X O 0 <1> (0 <o S3 S3 S3 0 (D tt) (U P3C3fi3 CO o T00 *H 3 tnimn CM CMOJ c m in rH H CM ll>4 ooo H *H *ri OOO a Pi Qi rt ri rl CO COCO 0 0 rH 0 0 H O H 3 CO / inin CM CM oo no OH >*>i OO HH OO Pi Pi H 4H coco trurun OJ OJ 0J O OOO ino o Hintn 5h H ooo rt H *rl OOO Pi Pi Pi rl *H *H CO CO CO u 0 uPHS O 0 _0_i I? 0 0 *H o H <H * CQ H in O fH rH H g ClJ |*J u O: mm CM CM OO-sfr MM oo H *H OO CU & d *H CO CO iruniAin <M c m o j c m o ia o winwrH Hw OwJ oooo rl trl "H *rl $O3 $O3 SO3 SO3 ft ft ft ft rl Tt <rl vH CQ CO W 03 Pi jrj S E S3 S' -rt *C J>s 60 d S-w ^* M 43 5^ T? -P 5O 6 fcH CO tCO H cosnSp3owfooa CO H rH tH lt 1 1 1 lilt 00 CO CO CO CO CO 00 CO CO 00 oo rH H o H oo iH H o ooo o H rH rH rH rH DUP050053761 o rH rH N- b- us; rH rH QO cd ON _ HI *0 6S fri O ON *H CD o CD H CD nH i P 53 & C6D0 O cd O oo o CD p CO rH S ><$ >H oo CdCVI oo \/ I PS qs X>H cTo sS oo \/ !25 9 PS 3& oo .CVJ.CU % o CVI OJ.OJ tS1 o \/ 0 oo1 srO8 a PS 1 PH s ao *0 rH ..CO CO CO 0 r CM a o1 -tog, B 9O19 CO O 0-09 - a yrn m 9 ow O W0CO-0ow CO GO P- ft <1) 9 B PS H CO J* cd 3 60 w0H po 3A: <<cu 2Ss 0) cd I <u CD 3 Ss CJ cd M O CD J& cd 3 cd M M 8' & GQ * * > . 60 rH H I! CD I cd a o cd <D P ^.co CD cd cd CD CD VO in i >afc 9 33 > H CO COO in in o * -G-OJ CO CO CM CM rH rH cd HCO' HOO rH pH O O (D N- PUP ft OO oa inn s in in in in in in 9 CM c m p CM CM CM CM CM CM in CM td cd O in vp o pP 60 o .CM \ vo o\ CO a rH OO o rH EH CD P o U CD rH f&cr in 3: CD <D -a CD tf S s60 P0 O~ O t>>OQ H in o n =s* n 9-5 1-5 rH rH & ft CD o o O *H o H CM in cd PS PS CD CD OI 60 60 P P P 11 ft 1*5 hD O fe fej H H ft ft ft in in in in CM CM CM CM p cd in ft rH o\ CM P-=t 1x5 CM o vp \ CM ^r CM H o p 5> uo JS-O c q ^Eh t- A CO in in in in 1S- > -- N- H i 89 s 1 9 9 98 co 00 00 co 00 00 CO 00 CO o oo o Q o o oo H rH rH rH rH rH rH rH rH DUP050053762 w o o o . CM w w p I cd o s 03 P O d *0 . in H W CD o H rt d 0o4 vi d CQ t0H) 3P 0u3 P CD C>D O ><D P O H O 03 iH d cd _ <D <H o*s CD H cd rd p o cd d 0 & H O p HP d cdP P Q (X< <D i . Pn H d on rl Pif C<QD dCISa OcdP03 CQ d U 03 M> &Q OPbCOOOhCO W& pp ^OJ 03 03 rH COLA o *1 mA* Pj o <j 1 I in mm CM CM CM CO 00 00 OOVOOO d! O O O 0 < ri H *H duo udo d uP_ rAdH-* pPdHMI rCdHM cm <d 1 PS d p p k CD P P Ai CD CD P> CD <D 3s Po O P T5 <D 03 S CD *C0D CD *H 03 CQ CO o 00 o OPCD H d rd OH ud HPd*CPoQ M cd cd CD SCBD >> coco coco VO *- pp dd oo 03 CQ * CD CD CM c--* CD <D bCM E CO O rH DUP050053763 CQ >| H P O P& 0 P <5--1, WO a! O 1 a. ah 0 cd 0P > 0 P % % t CQ CQ CQ P- O t 0 B 00 00 pcd 0 cd cd cd d P PP P P P P O P P P ^ S: > P 0 O BP O O PP P P P a a a 0 B U CQ >PK > A CQ CQ CQ CQ 0* Sc & * CQ P P CQ ^ 0 P CQ A CQ > P 0, btf C** <P H 0 O H Pc O0 P s CQ O 1 I I1 3 ,54 & *4 rH P CQ X> PX > > > 0> 0 H CQ O U *d 0 p -p 0 u A 0 u 0 P CQ 0 CQ <d A *H OO A0 P O P O O P 0 H cd rH CQ *& 0 CD d P H cd O rH H >> & XO 0 T* P PO O rH >> P 0 O8 rH & cd 0 0 *H P CQ 0 H d 0O P cd 1 rH O k V*H X OO P vj P 0 cd .X .X *2 Sc & ,24 P PP tt> X X X i4 > 0 00 * >> 0 U P X XP OS >*P rH O 0 OP p AO OO nr! P A cd O O A rH t >> 8 A OO O 0 O H P P B pi A Q O O P *d rH O P p P p P O CQ p P A vi cd cd cd H H DESOTO ACRYLIC EMULSION #2898 COMPATIBILITY HOT VERSUS COLD TINT1 0 O <2 A CQ O *^0| in ts* |I <Q CO CM in in 0* m CVJ CVJ CM CM 00 in ooon CM m 0 > rH 0 CVJ CQ OJ H0 P inC rH rH 00 vo in p * H 0 A r-f CM- a m 0 O mP O 0 CM 0 P* p O pp P p p pp 0 P 0p % OO CM P p0 P X ^ P O 0 O X& 0 0OO &1 O O 0 A A A'd P Acd P P 0 P P P rO P P P p P 0 P A CQ ca CQ <C <4 A CO A $6 A <4 A 0O P I P A ft AA OO A O O P AA 0 0 00 00 O 0 CO CO P CM CM CM CM CM CM 00 CM CM P P 0 rfd- 8 8 I8 8 1 38 8 18 0P 3 00 00 00 CD 00 00 0000 00 COCO 0 P P Js O O O O O 0 00 0 00 CQ A A A P p P P P p p p p p p DUP050053764 fe Sfc & moOo > dd d d d cd eg p eg eg PP o p P P pp 0p P P u pp P 03 03 03 0 0 W & SB p p CO P rH St * d 03 j> SB 0 03 0 > > > >> rH rH rH rH rH P O O O 6O d P P P PP <D o o O O O 0 < rH o rH O rH O C3 rH rH cd <d cd cd cd 08 8 0I U Pi U Pi Pi d 0 o> 0 0 0 P O p p P P P P Pp Pp p 03 03 0 0 0 P CO o mo m o oo 1I P-4 CM PH CM < o] tnoN < P-4 . CO o in tn in rHVO * OJ cu rH OJ W.OI1 in rH CM MH S'' <$ o rH VO rH dP CO CO 00 CO O O AP X X X H *H 0 03 03 03 3: d 0 d 0) d ^t-=o<d v n Pd Pd 0000 M A 0 Ph Ph -- fc- tS- o o H rH rH oooo 1 5 1 81 0o0 CD O CD O CoOCoO rH rH rH rH rH 0P ^JP H fctO rH d W0 Pi Pi P 00 50 dP pd Pi *rl PP 0 50 H dO H O a oo OP 0 p0 p C Pi O0 iH > P0 uu o Pi P^> rH T5 H 0 cd pd P0 P$ _0 ds O *rH H P P cd P rH d d0 O fH oo Q *H rH 0-1 <H d 00 P T5 od p cd p 00 a 0o 0P 0 nO S0 03 vH O d rH Cd rH P0 O 0a P d in iP 0H 3 0 P Pd d -h rH P * P rH D 0 P rH > O O0 ISOH rH *d 0 Pi a 0 P< Pi >> rH 0 CM d rH o *H > 0O Pi o Pi p H O S: P in T* rH 0 P3 TJ *d o cd H d CM o rH CPl rPHi CO oP oP p H H 3 IS bO d H nd rH 0 rH rd rH *0 s cd 3 CM Oh rH Oh o\ H o 3 oO oo p ri >> IS p p d d oa 0 o p rH cd 0 dd O rH *rH P P Pi Oh OO A_ od Pi o Pi*ri 0 P Pi O0 0A <*H 0 Ch *H CM d o *H 0 Pi 0 P. 0 H V 0 Pi cd P P>i P o p P P a 0 p p << oo O o p P d P 0 d p p 50 d 0 Pi P 0 0 P cd aH P rH D DUP050053765 VI. AQUEOUS DISPERSIONS REFERENCE #7 A. BW-461-P - Increased Strength (JJ AND RFW) Work has been contined on the modification of the BT-352-P route to an improved blue dispersion for DeSoto Paint. Emphasis has been placed on: 1. Development of optimum size reduction method and isolation techniques for making BT-352-P. 2. Development of optimum conditions for converting a high strength BT-352-P to an aqueous dispersion. A stronger BT-352-P (Lot 31308) has been produced by grinding the CPC crude with a higher Blancol ratio (15$ vs. 10$ toner basis) and an increased power input (45 vs. 25 Amps.), following Shriver washing to 7000 ohms and thickening to a solid of 25$ instead of the conventional acid extraction and Diphenyl Quanidine floccu lation. This product was then made into an aqueous dispersion util izing 50$ of EmuiphorEL-620. The product tested out satisfactorily versus Hilton-Davis Super Seatone Phthalo Blue in DeSoto Acrylic finish, and DuPont's "Lucite" and "Flowkote". Samples have been sub mitted to DeSoto Paint and F & F for evaluation. Experimental studies leading to this result are tabulated on the next page. DUP050053766 97 - NB 108-31 - Study of MyRJ-59 (polyoxyethylene stearate); Ethomeen C-25 (ethoxylated coco amine); EthornId HT-60 (hydrogenated tallow oil); Ethofat 242-60 (ethoxylated fatty acid); Ethofat 242-25 (ethoxylated fatty acid, higher POE). None of these surfactants was satisfactory in strength or hot tint compatibility. NB 108-32 - Study of Siponic E-15 (ethoxylated steary - cetyl . alcohol) Renex 20 (POE ester of fatty and resin acids); Sinclair 1440H (esterfied styrene - maleic anhydride copolymer); Dowfax 9N10 (ethoxylated nonyl phenol). A specially milled BJ-352-P (29809) was used. None of the products were adequately strong. All were poorer in hot tint compatibility. NB 108-33. 34. 35 - Study of Siponic E-15. Renex 20 Utilizing specially milled (104-13E) BT-352-P (high energy milled Shriver thickened) products exhibited adequate strength to the competitive, but were inadequate in hot tint eompatibi1ity. Addition of Defoamer, Nopco Chemical's Nopco L, NXZ, and NOW had little effect on strength and marked effects, on foam reduction. Addition of Witco's #912 agent to white tint base prior to addition of blue will correct hot tint compatibility. NB IO8-36 - Continuation of Studies on High Energy Milled BT-352-P Utilizing Renex 20 and Lioal 30W (ethoxylated vegetable oil). Cold tint strength was fairly close to the C#, Llpal 30W showed some improvement in hot tint compatibility versus standard agent, Renex 20. NB 108-37, 40 - Continuation of Studies using High Energy Milled BT-352-P Coupled with Siponic E-15, E-4 and E-15 Mixtures and a New Surfactant Emulphor EL-620 (ethoxylated castor oil). Strength was inadequate. Hot tint compatibility was very good when the latter agent was used at 25$ toner basis. Increasing surfactant level to 50$ gave rise to an excellent product, NB 108-39 - Continuation of Studies of Surfactants - Surfonic l6 & 17 (Structures Not.KnownExactly) and Adsee 85 (polyoxy ethylene thio Ether) None of these were adequate in hot strength compatibility. NB 108-43 108-40D was scaled up through homogenizer. Products were obtained which were stronger than the competitive and satisfactory in hot tint compatibility. DUP050053767 - 98 - NB 108-49 Various lots of Ernulphor EL-620 were tested for uniformity of effect in DeSoto1s vehicle. All worked satisfactorily, MB 108-57 Tests were made in Motile Paints acrylic (known to contain Methocel) to compare standard BW-431-P* Hilton-Davis Super Seatone* and experimental 108-43 type. The latter product was again for superior to BW-431-P arid satisfactory versus the competitive. MB 108-53. 55 108-43 type was scaled up successfully in the plant (BT-352-F - Lot 31308). MB 108-54 A study was made of other so called ethoxylated castor oils (Atlas G-1292> G-1295, G-1300). Some strength advantage over Ernulphor EL-620 was shown hut hot tint compatibility in DeSoto vehicle was inadequate. Red Shade Aqueous Dispersion Studies were undertaken to develop a red shade dispersed paste. These are summarized below. MB 108-41 N-623 (solvent milled Blue LB) was Jiffy milled with 35# Ernulphor EL-620. Products were weaker and duller than Harmon's Super Seatone Phthalo Blue and satisfactory in hot tint compatibility. MB 108-45. 47 Attempts to utilize Orchem1s acid pasted LB type pigment to develop a red shade product was unsatisfactory. Ernulphor EL-620 was used to make the dispersion. MB 108-48. 52 Attempts were made to use N-872 (acid swelled Blue R paste) to develop a strong red shade paste. Ernulphor EL-620 dispersions gave interesting strong red shade products, exhibiting good hot tint compatibility in the DeSoto vehicle. This process deserves further study. Siponic E-15 gave a dispersion exhibiting higher strength in Casein type dispersions. The use of acid swelled Blue R looks very interesting and will receive more study. DUP050053768 - 99 Stronger GW-749-P Studies were undertaken to develop a stronger GW-749-P utilizing the same approaches that lead to BW-461-P. These are summarized helow. m 108-42 Comparisons were made of Daxad 11 Siponic E-4 Siponic E-15 Renex 20 Emulphor EL-620 Emulphor EL-720 (more POE) utilizing a common GT-735-P (standard quality lot). Optimum strength levels and compatibility was achieved via the Emulphor EL-620 approach. NB 108-44 An attempt was made to increase the strength of GT-735-P by lowering the temperature of the standard acid extraction, and by eliminating the DPG flocculation. Products were obtained via Emulphor EL-620 use which were slightly stronger than standard GW-749-P. NS 108-46 Various isolation techniques were studied to isolate a smaller particle size GT-735-P from a special high energy milling. These compared 1. Standard acid extraction and DPG flocculation 195*5. 2. DPG flocculation 150*5. 3. ODCB and Ala(804)3 18 H2 flocculation 150*5. Route #2 gave the best result (si stronger than standard acid extraction and DPG flocculation) but inadequate to match the Harmon Super Seatone Phthalo Green. NB 108-50 Continuation of low temperature DPG flocculation (80P. ). Products obtained stronger than GW-749-P but not equivalent to competitive. DUP050053769 - 100 NB 108-56 Laboratory studies of HP milling initiated. This was a control run using Blancol. Standard strength level GW-749-? was achieved. NB- 108-57 .A study of the E. T. Oaks Corporation's pulverizer as a possible subst.itue for the homogenizer, showed that equivalent results were achieved. NB 108-58, 6l. 64 Attempts to HP mill with Polyfon T in the laboratory gave rise to stronger GW-749-P than that resulting from use of Blancol. Scale up in larger milling units is indicated. Products close to the Competitive in strength have been achieved. NB 108-59, 60P Purification via acid extraction, of N-770 seems to indi cate the possibility of achieving a higher strength GW-749-P via higher CPC purity. Should be coupled with best plant grinding conditions, if necessary. NB IO8-60, 64 HP milling withLomar D gave rise to relative small particle sized GT-735-P in the milling (as judged by particle size index) but the products after isolation via feasible methods were not as strong as those made with Polyfon T or higher amounts of Blancol. NB 108-63 Specially milled GT-735-P (higher energy input coupled with increased Blancol, ex plant milling, Shriver washed and thickened) was converted to dispersed pastes in the laboratory using Emulphor EL-620. The products are stronger than GW-749-P but are not quite as strong or intense as the competitive. Hot tint compatibility seems to be satisfactory. NB 108-62 Study of high ratios of Blancol gave rise to stronger GW-749-P, after modification of the extraction procedure. Both Polyfon T and high blancol type millings look interesting and will be studied further. The use of purified crude N-770 is also deserving of further study. DUP050053770