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Synthesis of α,ω-dicarboxypropyl oligodimethylsiloxanes by ion-exchange resin catalyzed equilibration polymerization

✍ Scribed by V.M Djinović; V.V Antić; J Djonlagić; M.N Govedarica

Publisher: Elsevier Science
Year: 2000
Tongue: English
Weight: 152 KB
Volume: 44
Category: Article
ISSN: 1381-5148
DOI: 10.1016/s1381-5148(00)00010-9

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✦ Synopsis

A series of a,v-dicarboxypropyl oligodimethylsiloxanes of predetermined molecular weights was synthesized from octamethylcyclotetrasiloxane, D , and 1,3-bis-(3-carboxypropyl)tetramethyldisiloxane (BCPTMDS) by a heterogeneously 4 catalyzed equilibration polymerization reaction using a macroporous cation-exchange resin as an acidic catalyst. The 1 1 3 structure of the obtained linear oligomers was verified by IR, H-and C-NMR spectroscopy, while their molecular weights 1 were determined by H-NMR spectroscopy, vapor pressure osmometry, functional group analysis and gel permeation chromatography. It was shown that the expected target molecular weights, ranging between 600 and 3500, were achieved with a satisfactory accuracy.

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