Reference

Intrinsic crazes in polycarbonate: phenomenology and molecular interpretation of a new phenomenon

Intrinsic crazes in polycarbonate: phenomenology and molecular interpretation of a new phenomenon. Dettenmaier, Manfred (Lab. Polym., Ec. 24936-68-3 and 25037-45-0 are also occured in this study. Polytech. Fed. Lausanne, Lausanne CH-1007, Switz.). Adv. Polym. Sci., 52-53, 57-104 (English) 1983. CODEN: APSIDK. ISSN: 0065-3195. DOCUMENT TYPE: Journal CA Section: 36 (Physical Properties of Synthetic High Polymers) The title subject was discussed on the basis of literature data and new exptl. data that utilized tensile, birefringence, and d. measurements, small-angle x-ray scattering, and SEM. It was demonstrated that intrinsic crazing of bisphenol A polycarbonate [24936-68-3] is a post-yield phenomenon occurring when the material is stretched to high stresses and strains in a temp. region close to the glass transition temp. The initiation of intrinsic crazes apparently is governed by a temp. and stress activated instability of the entanglement network frozen-in during the glass transition. An almost identical crazing behavior was also obsd. in stretched poly(Me methacrylate) [9011-14-7] and preoriented polystyrene [9003-53-6] at high stresses and strains in the vicinity of the glass transition temp. .

Photopolymerization of MMA in aqueous micellar solution

Photopolymerization of MMA in aqueous micellar solution. Wang, Erjain; Zhu, Deying; Feng, Xinde (Inst. Photogr. Chem., Acad. Sin.Chemicals with cas numbers 80-62-6 and 9002-93-1 also play role., Beijing, Peop. Rep. China). Gaofenzi Tongxun, (4), 274-80 (Chinese) 1983. CODEN: KFTTAR. ISSN: 0453-2880. DOCUMENT TYPE: Journal CA Section: 35 (Chemistry of Synthetic High Polymers) The kinetics of photopolymn. of Me methacrylate (I) [80-62-6] in micellar soln. was studied using Ph2CO [119-61-9] and Et3N [121-44-8] as catalysts. Catalytic effects of micelles in the polymn. of I with surfactants such as Na dodecanesulfonate [2386-53-0], cetyltrimethylammonium bromide [57-09-0], and Triton X 305 [9002-93-1] were obsd.; the ionic micelles were the more effective ones. The polymn. rate and mol. wt. of PMMA [9011-14-7] increased with increasing concn. of micelles in soln. The solubilization sites of the Ph2CO-Et3N-I system in ionic micelles were established indicating that the polymn. occurred in the micelle-water interface. The orientation of I in micelles resulted in an increase of the regularity of configurational sequences in the PMMA. .