POLYMERIZATION CONTROL IN CASTING OF METHYLMETHACRYLATE
DSpace at IIT Bombay
View Archive InfoField | Value | |
Title |
POLYMERIZATION CONTROL IN CASTING OF METHYLMETHACRYLATE
|
|
Creator |
RAMASESHAN, V
TRIVEDI, MK RAGHUNATHAN, TS |
|
Subject |
polymerization
methylmethacrylate bulk casting gel effect curing time temperature cycle |
|
Description |
This paper reports a technique for the controlled bulk polymerisation of methylmethacrylate initiated by benzoyl peroxide. Due to the high exothermic nature of this polymerisation process, casting of thin sheets and profiles must generally be carried out at relatively low temperatures and over extended intervals of time at a constant rate. Curing profiles of 6-12 h have been considered incorporating the kinetic features of polymerisation which includes a gel effect. The influence of the gel effect on the propagation and termination rate constants can be divided into two regions: one up to 20% conversion, and the other beyond it. In the first range the gel effect is independent of conversion while in the latter stage its influence is characterised by Ross-Laurence parameters. The study indicates that no advantage is gained through the employment of two-stage initiator loading. Curing cycles of longer duration can be generated for thicker castings from the analysis given.
|
|
Publisher |
JOHN WILEY & SONS LTD
|
|
Date |
2011-08-17T00:18:25Z
2011-12-26T12:55:13Z 2011-12-27T05:43:56Z 2011-08-17T00:18:25Z 2011-12-26T12:55:13Z 2011-12-27T05:43:56Z 1993 |
|
Type |
Article
|
|
Identifier |
POLYMER INTERNATIONAL, 32(3), 275-281
0959-8103 http://dx.doi.org/10.1002/pi.4990320310 http://dspace.library.iitb.ac.in/xmlui/handle/10054/9676 http://hdl.handle.net/10054/9676 |
|
Language |
en
|
|