Poly@-hydroxycinnamic acid) was synthesized by thionyl chloride activated polycondensation of p-hydroxycinnamic acid at ambient temperatures and by polycondensation of its various monomeric esters at elevated temperatures. The thionyl chloride activated polycondensation proceeds as a 2-stage process, yielding reduced viscosities of up to 102 mL/g. 360 MHz proton NMR spectra indicate an all-trans structure and the absence of side reactions. The polymer with a melting temperature of 313 "C can be pressed into films.Present address: Polyfibron Div., W. R. Grace Co., Atlanta, GA 30336. d, On leave of absence from the Facultad Quimicas, Universidad Nacional Autonoma de Mexico, 04510-Mexic0, D.F., Mexico. e, Systematic name: 3-(4-hydroxyphenyl)propenoic acid.Systematic name: frans-3-(4-acetoxyphenyl)propenoic acid. g, Systematic name: 4-hydroxyphenyl3-(4-acetoxyphenyl)propenoate.
Synopsisl-Methyl-3-methylenecyclobutene (MMCB) and 1,2-dimethylenecyclobutane (DMCB) copolymerized readily with isobutene with aluminum chloride as initiator in methyl chloride solution at temperatures from -95 to -78OC. No polymers were obtained with methylenecyclobutene (MCB) under similar conditions. The copolymerization of MMCB with isobutene took place through a 1,5-addition reaction while that of DMCB through both 1,2-and l,4-addition reactions. Large amounts of gel were present in the copolymers obtained from DMCB if the reaction was carried to high conversion. The commonly observed effects of dienes (i.e., rate retardation and molecular weight depression) on cationic copolymerization reactions were observed but to a much higher degree with these small ring dienes. The thermal crosslinking behavior of the resulting copolymers was investigated. In conjunction with the copolymerization studies, homopolymers of MMCB, DMCB, and 3,3-dimethyl-l-isopropylidene-2-methylenecyclobutane (IMCB) were prepared and their chemical structures examined.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.