Reference

Styryl-telechelic polyisobutylenes

Styryl-telechelic polyisobutylenes. II. Amphiphilic sequential copolymers of styryl-telechelic polyisobutylenes with vinyl acetate or N-vinyl-2-pyrrolidone. Keszler, B.; Kennedy, Joseph P. (Inst. Polym. Sci. 9003-27-4 and 26202-27-7 are also occured in this study., Univ. Akron, Akron, OH 44325, USA). J. Macromol. Sci., Chem., A21(3), 327-42 (English) 1984. CODEN: JMCHBD. ISSN: 0022-233X. DOCUMENT TYPE: Journal CA Section: 35 (Chemistry of Synthetic High Polymers) Section cross-reference(s): 36, 37 Styryl-telechelic polyisobutylenes [i.e., linear and 3-arm star polyisobutylenes capped with polymerizable p-styryl end groups (I and II, resp.)] were copolymd. with vinyl acetate (III) [108-05-4] or N-vinyl-2-pyrrolidone (IV) [88-12-0] by conventional free-radical techniques. The products obtained with I-III systems were sol., most likely branched isobutylene-vinyl acetate block copolymers (V) [26202-27-7], whereas those polymers [89678-91-1] prepd. with I-IV or I-IV combinations were networks consisting of polyisobutylene (VI) and poly(N-vinyl-2-pyrrolidone) (VII) sequences. That the copolymn. of I with III results in sol. products and that with IV yields networks is due to the very different reactivities of styrene with III and with IV. Hydrolysis of III units in V gave vinyl alc. (VIII) units, i.e., these products are branched block copolymers consisting of random III-VIII copolymer sequences connected to III sequences. The overall compn. of these sol. amphiphilic materials was detd. from conversion and mol. wt. data and by 1H-NMR spectroscopy; their mech. properties were examd. by stress-strain measurements. The compn. of amphiphilic VI-VII networks was calcd. from conversion and elemental anal. data. These gels bound both water-sol. dyes [methyl orange (IX) [547-58-0]] and hydrocarbons (C6H6) [71-43-2]. The 1st binding const. that characterizes the binding of IX by these VI-VII networks is 1 order of magnitude larger than that characteristic of the binding of this dye by cross-linked VII or by serum albumin. .

Photochemical polymerization of N-vinylpyrrolidinone in different solvents

Photochemical polymerization of N-vinylpyrrolidinone in different solvents. Allaev, Zh.; Gafurov, B. L.; Rashidova, S. Sh. (Inst. Khim. Polim. 78-67-1 and 9003-39-8 are also occured in this study., Tashkent, USSR). Uzb. Khim. Zh., (6), 37-40 (Russian) 1983. CODEN: UZKZAC. ISSN: 0042-1707. DOCUMENT TYPE: Journal CA Section: 35 (Chemistry of Synthetic High Polymers) The kinetics was detd. of polymn. of N-vinylpyrrolidinone [88-12-0] in EtOH and dioxane initiated by photochem. decompn. (l = 365 nm) of AIBN [78-67-1]. The rate consts. of the primary reactions were detd. by using 4-hydroxy-2,2,6,6-tetramethylpiperidinyloxy inhibitor and the rotating sector method. The polymn. was of the ~1.5 order in the monomer and ~0.6 order in the initiator indicating participation of the monomer in the initiation and chain termination by both recombination and disproportionation. The propagation rate consts. in EtOH at 25 and 40° were 1.4 x 103 and 2.03 x 103 L/mol-s, and the termination rate consts. of these temps. were 5.50 ′ 108 and 3.50 ′ 108 L/mol-s. The corresponding values in dioxene were 1.23 ′ 103, 1.87 ′ 103, 3.4 ′ 108, and 3.20 ′ 108 L/mol-s. The obtained polymers [9003-39-8] had mol. wts. 30,000-57,000. .