Fractionation of partially stereoregular poly(propylene oxide)

Date

1986-12

Author

Alyürük, K.
Özden, T.
Colak, N.

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Partially stereoregular poly(propylene oxide) samples were synthesized via reactions catalysed by a preformed analytically defined trimethylaluminium hydrolysate. These samples were fractionated into two contrastingly different fractions. 1. (i) D-polymers: This fraction constituted the major part (up to 90%). It mainly contained cyclic low molecular weight oligomers (MW < 1000). The linear chains found in D-polymers had hydroxyl end groups. No double bonds could be detected spectroscopically. 2. (ii) K-polymers: This fraction was high molecular weight stereoregular polymer. Stepwise thermal precipitation from dilute isooctane solution of K-polymers yielded a succession of fractions which differed in melting point. It appears that the phase equilibria during the thermal precipitations were not controlled by the molecular weights of species.

Subject Keywords

Organic Chemistry, Polymers and Plastics, Trimethylaluminium hydrolysate, Stereoregular, Poly (propylene oxide), Fractionation, End-group analysis, Cyclic oligomers

URI

https://hdl.handle.net/11511/52252

Journal

Polymer

DOI

https://doi.org/10.1016/0032-3861(86)90199-0

Collections

Department of Chemistry, Article

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Citation Formats

K. Alyürük, T. Özden, and N. Colak, “Fractionation of partially stereoregular poly(propylene oxide),” Polymer, pp. 2009–2012, 1986, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/52252.