Document M4v4QKvLEwrk5vEN164QK2Gmk

lbB87 Chemical Abstracts Vol. 78,1973 V5 Pr 16887r Mechanism of the thermal stabilization of poly(vinyl chloride) with metal carboxylates and epoxy plasticizers. Anderson, Donald F.: McKenzie, D. A. (Union Carbide Corp., Tarrytown, N. V.). Amcr. ('hern. Sue., Die. Org. Coatings Plast. Chem., Pap. 1971, 31(1), 740-56 (Eng). A model for degrading PVC |9002-8fi-2) (a mixt. of J-chtoro-2-hexenc (6734-98-1) ana 2-chloro-li-hcxene (28046-G2-0)) underwent rapid esterification as the main reaction in the presence of a mixt. of cadmium 2-ethylhexannatc (2420-98-6J and barium 2-ethylhexannate (2457-01-4), using cyclohexane oxide [286-20-4] as a model for the epoxy plasticizer. CdClj was formed in catalytic amts, as a byproduct, and catalyzed 2-hexen-4-yl-(2-chlorocyclohexyl) ether formation. The 2 reactions and the ligand transfer reaction between C'dt'L and BaCOi were related to the synergism obsd, in PVC thermal stabilization by combinations of epoxy plasticizers with Ba-Cd or Zn-Ca soap systems. The esters and chloroethers were thermally stable at 150'; at this temp., the PVC model degraded rapidly to HCI and 2,4-hexadiene. 16888s Comparison of stability tests for poly(vinyl chloride). Stiga, J. P.; Ryan, J. T.; Loan, L, D. (Bell Teleph. Lab., Inc., Murray Hill, N. J.). Amer. Chem. Soc., Dw. Urg. Coatings Plast. Chem., Pap. 1971, 31(11,757-62 (Eng). Values obtained for the discolorization, processability, and HC1 evolution of PVC (9002-8G-2) resins (both homo- and copolymers with, and without organotin stabilizers) exhibited only the most general correlations. The resin ordering in any one test was not reproduced by any other, indicating that a test closely related to use or processing conditions should be used to assess the relative usefulness of the resins. 16889t Incipient degradation of poly(vinyl chloride). Deanin, Rudolph D.; Borzenski, Frank J.; Watterson, Arthur C., Jr. (Dep. Chem., Lowell Techno!. Inst., Lowell, Mass.). Amer. Chem. Soc., Die. Org. Coatings Plast. Chem., Pap, 1971, 31(1), ,763-9 (Eng). The incipient degradation of PVC (9002-86-2) was detd. by measuring the degree of unsatn. that occurred before visible discoloration using ir spectroscopy. The ir spectroscopy ' was a measure of incipient degradation throughout all the aging period before initial color change for Ba-Cd-Zn stabilized PVC plastisols, for degradation during the last 33% of the time before initial discoloration for the dynamic aging of Ba-Cd-Zn rigid formulations, and for the last 53% of the time before initial discoloration for Sn-Rtabilized plastisols. For the dynamic aging of Sn rigid formulations, ir spectroscopy measured degradation during the last 50% of the time before initial discoloration; but for Pb-stabilized systems, no ir absorption was obsd. to indicate increasing unsatn. 16890m Predicting long-term creep of polyethylene. Putans, A.; Urzhumtsev. Yu. S.; Kalnroze, Z. (USSR). Polim. Mater. Vod. Khoz. 1971. 28-38 (Russ). From Ref. Zh., Khim. 1972, Abstr. No, 3S772. Isothermal creep data for low-pressure polyethylene (9002-88-4) at const, temps, and nonisothermal creep data obtained during thermal cycling showed that creep deformation during cycling grew significantly compared with the isothermal creep at the av. temp, of the cycle; in time the nonisothermal deformations became larger than the isothermal deformation at the max. cycle temp. An approxn, of the relaxation spectra as a generalization of the Charles distribution law is given and used to predict isothermal creep at extended times, based on short term high temp, test data. When the method was applied to nonisothermal creep evaluation, there was good agreement Jbr short-term creep, but significant error at extended duration 16891n Faciors affecting water vapor transmission through free polymer films. Swarbrick, J.; Amann, A. H.; Lindstrom, R. E, (Sch, Phcrm., Univ. Connecticut, Storrs, Conn.). J. Pharm. Sci. 1972. 61(10), 1645-7 (Eng). Significant ermeation differences from expected behavior existed with ydrophilic cellulose acetate phthaiate (I) 19004-38-0] films when the atm. adjacent to the distal surface of the film was devoid of water vapor; no such effect was obsd. with lipophilic poly(Bu methacrylate) |9003-03-8) films. The effect increased with temp, and was due to partial dehydration of the I film. The method of film prepn., e.g. casting or spraying, did not affect the permeation charat i eristics of the I films. 16892p Structural processes during heat treatment of oriented polyethylene with straightened chains. Zubov, Yu. A.; Sukhov, F. F.; Selikhova, V. i.; Bakeev, N. F. (Fiz.-Khim. Inst. im. Karpova, Moscow, USSR). Dokl. Akad. Nauk SSSR 1972, 206(2), 384-6 |Phys Chem) (Russ). X-ray diffraction of cryst. polyethylene 11) |9002-88-4), obtained hy compression (7000 kg^cm-1) at 270 (Zubov. Yu. A., et al., 1970). shows that healing causes thermal expansion ol its crystals in the plane (Li:o) normal to the direction of its aligned chains. Healing 1 rontg. crystallites with folded chains causes no change in Lnn. This difference is caused by the differences in the space (crystal defects) available for expansion: in 1 contg. the aligned chain bundles the defects are large and can be filled-in during the thermal expansion, while in I contg. the folded-over chain bundles such spaces are small and insufficient for the inner expansion of the crystallites. 16893q Critical, two-dimensional tensile deformation polymers and the mechanism of liquid permeability. Man: V. N.; Gromov, A. N. (USSR). Uokl. Akad. Nauk SSSR 1!'.: 206(2), 414-17 (Chem Technol) (Russ). The permeability coe: (x) of unstretched or biaxiallv oriented polyethylene < |9002-88-4| or poly(tetrafluoroethylene) (II) (9002-84-0) fib toward heptane do not depend on the hydrostatic pressure f/'i liq. when the deformation (8) is sub-crit. When A/A,.,,, was > x of I slightlv decreased while x of II increased when P w: increased. These differences are explained by the absence . microfissures or small defects in I and their piesence in ll. 1 with large mech. anisotropy (i.e., the ratio of the elongations r break in 2 perpendicular directions) acquired a large no. , defects when stretched bi-directionally and have high x when th crit. A is reached. The x detn. of biaxially oriented filir provides a measure of the no. of defects in these films. 16894r Packing density of macromoleculcs in th polyethylene-surfactant-modified asbestos system. RevyaU M. M.; Markina, A. Ya. (Beloruss. Tekhnol, Inst. im. Kirovc Minsk, USSR). Vestsi Akad. Navuk Belarus. SSR, Ser. Khim Navuk 1972, (5), 55-8 (Belorussian). With increasing asbestc and surfactant concns., the packing d. of surfactant rnodilic asbestos-filled polyethylene (9002-88-4) (contg. 5-30% a"bestos increased (from 0.946 to 1.145 g/cm1), regardless of the surfactan compn., the Brinell hardness increased, but \vassurfactant-comp= n.-dependent, and the water absorption decreased to at absorption tomp.-independent min. with OP-7 surfactant, Th' Brinell hardness values for OP-7 and 246 prepn. compns. wer< higher than those of sulforicinoleale surfactant ones. J. Malek 16895s Measurement of the normal stress difference usinr the Barus effect. Funatsu, Kazumori; Mori, Yohiro (Fac Eng., Univ. Kyushu, Fukuoka, Japan). Kobunshi Kagaki 1972, 29(9), 638-42 (Japan). The first normal stress differenti of polypropylene (9003-07-0) at high shear rates detd. by usinf. the Barus effect assuming the strain generated inside the nozzle completely relaxed after the fluid emerged from the nozzle agreed with the value ealed. from the exit pressure at the tube end. The result for polyethylene (I) [9002-88*4] was ~30% smaller than the literature values. The first normal stress differences of I extruded through a capillary and a slit varied -20%.. 16896t Contact charge-transfer absorption spectrum between polystyrene and oxygen. Tsubomura, Hiroshi; Yamamoto, Naoto; Akaishi, Satoru (Fac, Eng. Sci., Osaka Univ., Toyonaka, Japan). Kobunshi Kagaku 1972, 29(9). 657-61 (Japan). The absorption spectra at -- 273 nm and <260 nm of polystyrene (1) (9003-53-6) film in high pressure 0 increased the intensity with increasing 0 pressure and were assigned to the contact charge transfer absorption due to the interaction between the I Ph groups and O. The direction of the transition moment of the contact charge transfer band detd. for a stretched 1 film was nearly perpendicular to the Ph ring plane. 16897u Crystallization kinetics of isotactie polypropylene in the presence of colloidal particles of lead. Zharinova, T. A.; Deinega, Yu. F.; Ulberg, Z. R.; Nizhmk, V. V.; Mikhailov, B. A. (Inst. Kolloidn. Khim. Khim. Vodv, Kiev. USSR). L'kr. Khim. Zh. (Russ. Ed.) 1972, 38(10), 989-93 (Russ). The rate of growth of spherulites in isotactic polypropylene [25085-53-4) was investigated in the presence of colloidal lead J7439-92-1] particles (i|5%) at different cryst. temps. 0 38-56). The presence of colloidal particles increased the no. of crystn. nuclei and decreased the induction period of crystn. Max. growth rate (at 150) was obsd. at 0.57c concn. of colloidal Pb: further increase in Pb concn. decreased the growth rate to a const, value about the same as at 0.17c Pb. lG898v Effect of glow discharge on the adhesion properties of fluoroplastic materials. Stepanova, 1, A.; Zayats, A. I.; Kublanovskaya, A. 1. (Inst. Obshch. Neorg. Khim., Kiev, USSR). Ukr. Khim. Zh. {Russ. Ed.) 1972, 38(10), 1018-21 (Russ). When Ftoroplast F~4 (I) (9002-84-0) is exposed to an ionized gas discharge in partial vacuum its surface acquires CO, OH, and other groups more reactive than CF_, groups. Such 1 has '10-14 kg/cmJ adhesive strength to Ni or Pd. The exposure to glow discharge modifies the ir spectra of 1; these changes are discussed. 16899w Structural changes before the start of necking in polyethylene. Narzullaev. B. N.; Nizamidinov, S.; Slutsker, A. 1.; Yastrebinskii, A. A. (Tadzh. Gos. Univ. im. Lenina, Dushanbe, USSR). Dokl. Akad. Nauk Tadzh, SSR 1972. 15(81, 18-20 (Russ). X-ray diffraction shows that p-./vo.'/tv lenv (!) 19002-88-4) film elonsatcd until there i* r.r-rkirv; hr--v- progressively more oriented. Similar conclusions are reached bv observing the sepn. between marks on 1 surlace in the vicinity ot the progressing neck; the sepn. decreases as the distance from the neck increases. 1690Oq Velocity of sound and other condition functons of plastics. Schenkel, Gerhard (Stuttgart, Ger.). Kunststv/fe 1972, 62(9), 575-80 (Ger). The sound propagation rates in polystyrene (9003-53-6), PVC (9U02-S6-2), puMA/c methacrylate) 19011-14-7], and polyethylene |9002-88-4] are ealed, as functions OLI 7389