Cationic Polymerization and Related Problems

Wavelength tunability in photoinitiated cationic polymerization

Onium salts, widely used cationic photoinitiators, have absorption in the short wavelength of the UV spectrum. However, their spectral sensitivity can be tuned up to the visible region by using several methods. Photosensitization of onium salts, their charge transfer complex formation and their free radical promotion are some techniques that are used to provide wavelength flexibility. This chap...

Writing and Related Problems for EFL Students

ESL students who write in English may present written material in a rhetorical and organizational mode that reflects the pattern which is valued in their native culture and rhetoric. Considering the violation of English code of writing in the writings of Iranian students, we will notice one common characteristic: They are reluctant (or ignorant of) to write a unified paragraph. Their writing co...

Observation of eliminative cationic polymerization within van der Waals clusters

Cyclic Oligomers in the Cationic Polymerization of Heterocycles

The cationic polymerization of heterocyclic monomers may lead to polymers containing substantial, yet Variable amounts of cyclic oligomers. This review gives a survey of the systems where such oligomers have been found. Oligomer formation is generally observed in the polymerization of oxiranes and thiiranes. The most frequently observed oligomers are the cyclic dimers and cyclic tetramers but o...

Preparation of cationic polyacrylamide by aqueous two-phase polymerization

Cationic polyacrylamide (CPAM) was synthesized by aqueous two-phase polymerization technique using acrylamide (AM) and dimethylaminoethyl methacrylate methyl chloride (DMC) as raw materials, aqueous polyethylene glycol 20000 (PEG 20000) solution as dispersant, 2,2′-azobis(2-amidinopropane) dihydrochloride (V-50) as initiator and poly(dimethylaminoethyl methacrylate methyl chloride) (PDMC) as st...