Document BvDj5MBQXq9KVqMO80Vpwk7xj

Period Covared MAY, 1966 to NOVEMBER, 1966 FILE, 14! d a t e , 12/19/66 S.C. DEC 2 2 1966 N39906 KN-66-11 Copy No. <d" 1. Numerical File 2. Research Office File No. 141 3. library File No. 141 4. M. Hunt/E. Gonick, Pigts., Wilmington 5. N.G. Fisher, Central Research, Wilm. 6. P. J. Monahan ( X File ) 7. J.R.Giacin 8. H. R. Linton/B. H. Perkins/F. F. Ehrich 9. W.S,Struve/A, A.Brizzolara/Library 10. Extra 11. Extra 12. Extra 13. Extra 14. Extra 15. Extra NEWARK PLANT PIGMENT COLOR RESEARCH REPORT SUBJECT: PIGMENT PHOTOCHEMISTRY PERIOD COVERED: MAY, 1966 to NOVEMBER, 1966 SUBMITTED BY: J. R. GIACIN APPROVED BY; F. F. EHRICH Date Submitted: 12/12/66 Date Released: m7 ABSTRACT: NE 1834 An extensive series of quinacridonequinone/N,N' diphenyl-p-phenylenediaraine solid solutions was prepared; and the samples were evaluated for outdoor durability. Quantitative studies were carried out on quinacridonequinone/ N,N'-diphenyl-p-phenylenediamine solid solutions under anaerobic conditions,and the rates of photodegradation of quinacridonequinone were determined. DUP050053869 INTRODUCTION Previous workers have shown that the photos tabillty of qulnacridonequlnone (QAQ) is Increased when N,N*-diphenyl-pphenylenediamine (DPD) is incorporated into solid solution with qulnacridonequlnone. A simple admixture appears to have no effect. A quantitative study was carried out on both quinacridonequinone and quinacridonequinone/N,N` -diphenyl-p-phenylenediamine solid solution with the long range objective of eluci dating the mechanism of qulnacridonequlnone photodegradation and the mechanism by which the N,N' -diphenyl-p-phenylenediamine Inhibits the degradation of qulnacridonequlnone. These studies were carried out by incorporating the quinacridonequinone or quinacridonequinone/N,N*-diphenyl-p-phenylene diamine samples into "Butacite" laminates and irradiating the slides. This technique affords an anaerobic system which can be studied by visible spectroscopy. RESULTS AND DISCUSSION An extensive series of quinacridonequinone/N, N' -diphenyl-pphenylenediamine solid solutions was prepared and the samples were evaluated for outdoor durability. In this study, the solid solutions were prepared with both recrystallized and crude qulnacridonequlnone (the crude QAQ was found to contain 2.4# CrOs). The samples were evaluated in "Incite" acrylic lacquer, and in 32J aerylife enamel. The samples were evaluated in both paint systems as metallies at aluminum concentrations of 10# and 75#. The samples were also evaluated in both paint systems as tints at a toner concentration of 95#. In all cases, the paint systems were evaluated both with and without nickel carbonate. The results of this study after three months exposure are tabulated in the following Exposure Series #66477, DUP050053870 . -2- 1. W,S,Struve/A.A.Brizzolara/Res.Pile. 2. B.H.Perkins/B.J.Godfrey, Newark 3. P.P. Ehrlch/W.J.Marshall, " 3 4. J.R, Giacin 5. Extra 6. Extra 7. Extra Newark# New Jersey June 24, 1966 SERIES NO. 66477 EVALUATION OP THE OUTDOOR DURABILITY OP A SERIES OP SOLID SOLUTIONS , ' PREPARED PROM QAQ/DPD 3gJ TOe a c k y UO ENa mEL OBJECT: (a) Evaluation of a series of QAQ/DPD solid solutions for durability evaluation, with purified QAQ being used in the 1834/15 series and plant material being used in the 1834/25 series# (b) To examine the effect of NiCCb on pigment durability. PIGMENTS EVALUATED: The following with and without NiCOs TBM-m - `Pure Q!AQ (recrystallized from HaS04) 15B - QAQ/DPD solid soln. ISO - " 15D I >' 15E - ii 11 n 11 11 ii it ii ii 15P i n n *i initial 11 ii ti it ratio 99$/l# 11 95%/5$ ii 90%/l& mi 8WlS ti 805^/205$ 150 - Pure DPD 15H - Admixture QAQ/DPD ratio 9 151 ~ ii ii I* 80: 25A - Crude QAQ 25B 250 _ QAQ/DPD it ii solid ti soln. 25D 25E ^ if ti ii ii ii ii 25P _ ii ii ii initial ti it it ti ratio 99; ii !! II II 250 - Admixture - QAQ/DPD ratio 25H _ ti ti ii ii 1.6A - Pure YT-752-D 16B - YT-752/DPD solid soln. - initial cone. 99#/l# 16C - YT-752/DPD 16D I"VII " *' " 95: "" 9 io# 16E - Admixture YT-752/t>PD ratio 95#/ 16P " " 90^/K REFERENCES: R/W 66-343A, 344A# S-66480 "Lucite" Lacquer EXPERIMENTAL DETAI LS : Vehicle: Aroset 777/Cymel 243-3, 70/30 on vehicle solids Means of Grinding: 1/2 pt. Jar - steel balls Drying Schedule: Baked 1/2 hr. at 250*F.* Pigment Binder (P/B)t 14/100 Other Data: Alcoa #726 aluminum was used to prepare the metallies. "TiPure" R-902 was used to prep* the tints of the enamels. EXPOSURE: Means of Application: Spray Panels and Finishes Prepared by: J. J.Pox ) Start of Exposure: Pla, July, 1966 LOCATION SETS TYPE PANEL AND SIZE PRIMER COATING PANEL MARICJ.V Pla.S^S 2 Aluminum 4x3.2 Preparakote 65-3012 P-A, B B. J. OODPREY/J. R. OIACIN RESEARCH DIVISION DUP050053871 Panel '1 ' 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 Pigment 1834-15A 15A + NiCQa 15B 15B + NiCOa 150 ISO + NiCOa 15D 15D + NiCOa 15E 15E + NiCOa 15P 15P + Nicoa ISO 15G + NiCOa 15H 15H + NiCQa 151 151 + NiCOa 25A 25A + NiCOa 25B 25B + NICQa 250 250 + NiCOa 25D 25D + NiCOa 25E 25E + NiCOa 25F 25P + NiCOa 25G 250 + NiCOa 25H 25H + NiCOa 16A 16A + NiCOa 16B 16B + NiCOa 160 16 C + NiCOa 16D 16D + NiCOa 16E 16E NiCOa 16P 16P + NiCOa RT-795-D 1834-15A 15A + NiCOa 15B 15B + NiCOa 15 C 150 + Nicoa 15D 15D + NiCOa 15E 15E + NiCOa 3 S-66477 Ai/Toner WIt 9"0 ... II It II II II II It It II II II II II II II II tt 11 II II II 11 11 II <1 11 It 1! II II 11 II II 11 11 II M II 11 It II II It 11 It 7II 5/25 II It II 11 It It II H Initial Gloss 20 fit """fid"'-----91 1089 6<J 91 10- 92 88 94 8f 81 9f 87 St 88 It 90 -7f 84 -7f 88 -It 89 2f 88 0 90 7d 88 7f 91 6d 88 It 82 -6d 86 -10 88 6d 90 9,5 68 fid 88 6f 85 5f 88 6f 86 5f 88 6f 87 -St 92 -5f 87 6d 86 9.5f 87 4d 87 9f 86 8f 89 9* St 90 9.5f 89 10 88 9f 88 95f 89 8f 88 9t 87 St 87 9t 88 9f 89 8f 82 9.5f 71 At 75 at 74 St 79 9t 80 St 69 9f 78 8f 75 1074 7f 72 9t DUP050053872 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 86 89 90 91 92 93 94 Tin 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 1834-15F 15F + NICCfe 15G 15G + NICCfe 15H 15H + NICO3 151 151 + NICCfe 25A 25A + NICCfe 25B 25B + NiCOa 250 250 + NICCfe 25D 25D + NICCfe 25E 25E + NIGO3 25F 25F + NiCOa 25G 25G + NICCfe 25H 25H + NICCfe 16A 16A + NICCfe 16B 16B + NICCfe 16C 16C + NICCfe 16D 16D + NICCfe 16E 16E + NICCfe 16F 16F + NICCfe RT-795-D, 97189 5/95 Toner/White 1834-15A 15A + NiCOa 15B 15B + NICCfe ; 15C 15 C + NiCOa 150 150 + NICCfe 15E 15E +' NI CCfe 15F 15F + NICCfe 15G 15G + NICCfe 15H 15H + NICCfe 151 151 + NICCfe -4 S-66477 7H 5/25 11 I! 11 If 11 11 U It M M 11 11 11 M It It 11 11 ii n ii it 11 11 11 u 75/25 u tl II 11 11 M It II 76 78 62 79 77 78 79 82 79 75 82 83 87 79 81 81 77 78 82 83 78 82 82 82 76 76 81 80 77 75 79 83 81 84 83 77 72 72 77 . 78 83 74 77 74 76 83 80 79 78 82 80 66 72 63 74 8f 8f 41 4f 4f , 8f 4f 8f 0 10- 3f 8f St 109f 100*5f 9f 7.5f 9f 0 10- 0 Sf 7f 9f 9. St 10- $f 10- 9f 10 7f 9 5f 7f 95f 10 3f 8f 4f 10- st 9f 5f 7 St 5f 5f St 0 2f 3t 8f 3f 8f DUP050053873 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 1834-25A 25A + NlCQs 25B 25B + NiCOs 250 250 + NiCCb 25D 25D + NiCCb 25E 25E + NiCOb 25F 25F + NiCOs 25 G 250 + NiCOs 25H 25H + NiCOb 16A 16A + NiCCb 16B 16B + NiCCb 16 C 16C + NiCOs 16D 16D + NiCOs 16E 16E + NiCOs 16F 16F + NiCOs RT-795-D YT-748-D 10/90 " 75/25 5/95 Both sets at 5S -5 3-66477 72 If 78 9.5f 82 2f 81 10- 73 3f. 75 7f 78 5f 85 7f 62 5f 61 5f 60 5f 69 5f 73 2f 78 8f 77 If 72 8f 72 6f 79 '8f 75 6f 66 7f 75 5f 76 6f 75 4f 78 4f 68 6f 76 8f 78 6f 81 7f 73 10 86 8.5f 74 8. 5f 73 6f y DUP050053874 6 S-64480 "LPCITE11 ACRYLIC LACQUER Panel Pigment Initial Gloss 20' Metallies 75/25 Al/Toner 1 2 3 4 5 6 7 8 9 10 11 12 13 14 1834-ISA 158 15 C ISO 15E 15P 15H 151 16A 168 160 160 1633 16F + NiCftOs If II !Y II (I tl If 1! If It It 11 15 RT-795-D 52 5f 40 6d 34 6d 29 9.5 27 if 51 it 43 5f 37 4f 31 9f 52 9.5 44 9.5 40 8f 36 6f 32 Sf 63 10 Tints 16 17 18 19 20 21 22 23 24 25 26 27 28 29 '30 31 32 5/95 Toner/White 1834-15A 15B 150 150 15E 15P 15H 151 16A 16B 160 160 16E + NICItO3 II 11 I! It M It It It It It It 16P If RT-795-D 72 3f 72 5d 63 7d 70 7f 72 5f 63 51 74 3f 73 3f 67 71 70 1060 71 49 51 73 51 66 51 63 9.5 71 81 DUP050053875 -7 - In an attempt to determine the role played by the N,N* - diphenyl-p-phenylenedlamine as a stabilizing agent for quinaeridonequinone, a series of solid solutions was examined by infrared spectroscopy in the N-H and 0=0 stretching regions. data obtained are tabulated in Table II. The TABLE II Sample QAQ/DPD 10C$/0# 99^/1^ 95^/5$ Average N-H3, 3.243-0.001a 3.25 tO.OOlu 3.246to. 001 |x Average N-H 3.298to. 001a 3.296to.001u 3.297+O.OOlu Average CmD 6.15 to, 001a 6,l53t0,001a 6,152to,001a 3Q$/l0fo 3.252to. 001(X 3.297^0. 001a 6.153-0.ooia 85&/15& 80&/20& 3. 25lt0. OOlp. 3.25li0.001u 3.300u 3.300a 6,153t0.001a 6,153^0.ooia a - Infrared frequencies reported are the average of three individual measurements. It can be concluded that the incorporation of N,N* diphenyl-p-pnenylenedlamine into solid solution with quinaeridonequinone has little or no effect on the N-H and C=0 stretch ing frequencies of quinacridonequinone. In a continuation of the study of quinacridonequinone photochemistry, a series of quinacridonequinone/N,N' -diphenyl-pphenylenediaraine "Butacite" laminates was prepared and the slides were exposed. The degradation of quinacridonequinone was followed by measuring the visible spectrum and obtaining the change in optical density at 420ma. A plot of the data obtained from this experiment showed the disappearance of the quinaeridonequlnone followed a first order rate expression, d (QAQ) k (QAQ) dt A tabulation of the rate constants obtained is listed in Table III. TABLE III K x 10a hrs."1 "379" 3.2 3.7 3.2 3.4 DUP050053876 -8* From these results It was concluded that N,NI -diphenyl-pphenylenediamine does not enhance the photostability of quinacridonequinone in the absence of oxygen. This is in contrast with its effect in the presence of oxygen. This finding was confirmed in another experiment. It was shown that in the absence of oxygen, quinacridone quinone , which is incorporated into a "Butacite" laminate, will undergo a rapid photoreduction to give 6,13-dibydroxyquinaeridone hr. RH The 6,13-dihydroxyquinacridone was found to be unstable toward oxidation back to the quinone. Although the qulnacridonequinone was shown to undergo photoreduction in the absence of oxygen, the reduction reaction may not be a quantitative process and the loss of quinacridonequinone under these conditions may be accounted for by a photoreduction process plus secondary processes. Still to be answered is the question as to whether photoreduction is a chemical process whereby the quinacridonequinone undergoes degradation upon outdoor exposure. To determine the wavelength and/or wavelengths of light responsible for initiating photoreduction of quinacridonequinone, a series of quinacridonequinone "Butacite" laminates was i exposed employing various filters. The disappearance of the 420mu absorption band was followed and the rate constants determined. The data are tabulated in Table IV. TABLE IV Experimental Conditions K x 102 hrs. 1. No filter 2. No filter - quartz slides 3. 350m|a, cut-off filter 4. 325-385mu transmittingfilter 5. 400m|J. cut-off filter 6.0 7.4 8.16 16.6 17.0 It is concluded from these experiments that photoreductlon of quinacridonequinone can be initiated by a visible and/or ultraviolet light source. The 400mix cut-off filter and the 325-385m|.i transmitting filter were examined after irradiation and no deterioration was detected. DUP050053877 -9 - A series of "Butacite" laminates of quinacridonequinone, quinacridonequinone/N, N1 -diphenyl-p-phenylenediamine solid solution and quinacridonequinone/quihacridone solid solution ("Newport" Gold) was exposed and the rate constants for the disappearance of quinacridonequinone determined. The data are tabulated in Table V. Sample QAQ QAQ - Bure QAQ - Pure QAQ/QA 75#/25$ QAQ/QA 75%/25% t abl e; V Average K8, 8.2 x 103Sh* rs."1 9.2 x 102hrs.*"x QAQ/DPD 80%/20% QAQ/DPD 80//20% 8*2 x 10ahrs."1 a - Average value for two runs. It was concluded that neither the N,N-diphenyl-p-phenylenediamine nor the quinacridone will enhance the photostability of quinacridonequinone in the absence of oxygen. These findings are in contrast with the results obtained in the presence of oxygen. SUGGESTED WORK ON QUINACRIDONEQUINONE PHOTOCHEMISTRY 1. Prepare solid solutions of quinacridonequinone and substituted p-phenylenediamlnes. The two phenylenediamine derivatives suggested are: fa) N,N' -bisfp-nitrophenyl)-p-phenylenediamine (b) N,N' -bis(p-methojiyphenyl)-p-phenylenediamine Their effect on quinacridonequinone photostability should be evaluated both in a laminate and under outdoor conditions. 2. Effect crystal growth of quinacridonequinone and determine the effect of particle size on the rate of photo reduction. 3. Exposure of quinacridonequinone and quinacridonequinone/N,N* -diphenyl-p-phenylenediamine solid solutions under various atmospheres and determine their effects on photoreduction. ' This procedure s hould afford a means of determining whether the reduction of quinacridonequinone to the dihydroxy- derivative and its reoxidation to starting material are quantitative processes. It is suggested that the photolysis be carried out under ijd) NO DUP050053878 4. Determine the intrinsic viscosity of the "Butacite" resin and determine the effect of its exposure in the presence of quinacridonequinone on the intrinsic viscosity. Such a study could determine whether quinacridonequinone was under going reduction to either its serai-quinone or the dihydroxy derivative in the presence of oxygen, since the radical reactions undergone by the "Butacite" resin should be nonreversible* 5, Devise experiments to determine whether the quinacri donequinone reacts in the singlet or triplet excited state* This may be done by employing triplet quenching agents and determine their effect on the rate of quinacridonequinone photoreduction. The quinacridonequinone may also be employed as a possible sensitizing agent. Per example, it might be employed as a sensitizing agent for the photo, oxidation of tetramethylethylene. This oxidation requires singlet oxygen which is obtained through a triplet-triplet annihilation reaction involving a triply excited species and ground state oxygen. EXPERIMENTAL The infrared spectra were recorded on a Perkin-Elmer 21 spectrophotometer as mujol mulls. The visible and ultraviolet spectra were recorded on a Beckman DtJ spectrophotometer. All laminates were prepared with glass slides unless otherwise stated. All exposures were carried out with a carbon arc light source unless otherwise stated* PREPARATION OP SOLID SOLUTIONS Pure samples of quinacridonequinone were obtained by recrystallization from cone, sulfuric acid* The N,N* -dlphertylp-phenylenediamine used was recrystallized several times from ethanol and then methylenechloride* Crude quinacridonequinone was used In the preparation of several samples for outdoor evaluation. The samples used in the rate studies employed recrystallized quinacridonequinone. The solid solutions were prepared by salt milling. The solid solutions were assayed for quinacridonequinone and N,N' -diphenyl-p-phenylendlamine. The quinacridnn^xnone was analyzed by visible spectroscopy, Tb/-> w. r -uiphenyl-p-phenylenediamine was first extracted from K*e solid solution by continued saxlet extraction with methanol and the cone, determined spectroscopically* The x-ray diffraction patterns taken showed the absence of a peak char acteristic of N,Ntdiphenyl-p-phenylenediamine although control experiments, showed that the N,N'-diphenyl-p-phenylenediamine was present in concentrations great enough to afford characteristic peaks if it was present as a simple admixture. Prom this evidence it was concluded that solid solution had been attained. DUP050053879 - 11 DETERMINATION OF RATE CONSTANTS The laminate slides were exposed and the absorption spectra were recorded at pre-determined time intervals, The rate studies were based on the disappearance of the 420mu absorption bend characteristic of quinacridonequinone. A first order rate rela tionship was obtained by plotting the log of absorance (420mu band) vs. time. A least squares calculation was used to obtain the slope and to fit the data points. The rate constant was ob tained from the slope by the relationship: K 68 .3 Slope 6,13-DIHYDR0XIQUINACRID0NE An authentic sample of 6,13-dihydroxyquinacridone was prepared by chemical reduction of quinacridonequinone by sodium hydrosulfite. Twenty (20) grams of quinacridonequinone was dissolved in 250 ml. of 50,0$ sodium hydroxide solution and charged into a 5 liter flask. Five hundred (500) ml. of water and 1,000 ml. of dimethylformamlde were also charged into the flask. The reaction mixture was stirred and maintained under a nitrogen atmosphere. To the reaction mixture was added 500 ml. of sodium hydasbsulflte saturated solution, at a dropwise rate. The temperature was maintained at 50. After complete addition, the reaction mixture was filtered under a nitrogen stream and the filter cake was washed until the filtrate was base free. A sample of the 6,13-dyhydroxyquinacridone was dried under a nitrogen atmosphere under reduced pressure and sublimed nto a quartz slide. The visible and ultraviolet spectra were immediately measured. The visible spectrum showed a broad band between 556-65011^. Upon inadlation of quinacridonequinone laminate the development of a broad band between 550-650m|j was assumed to be characteristic of the reduction product. Exposure of the 6,13-dihydroxyquinacridone to oxygen afforded a rapid oxi dation to the parent qhinone. This reaction can be carried out as a dark reaction, or can be photo initiated. DUP050053880