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Title: Local Glass Transition Temperature T g ( z ) Profile in Polystyrene next to Polybutadiene with and without Plasticization Effects
Abstract

Rubber toughening of glassy polystyrene (PS) has been manufactured commercially for decades as high impact polystyrene, where rubbery poly‐butadiene (PB) inclusions are added to modify the PS matrix response to deformation and impact. In this study, measurements of the local glass transition temperatureTg(z) of PS next to PB rubber are presented, expanding the previous data to a polymer with a much lowerTgvalue (PBTgbulk= −96 °C). After accounting for a small molecule additive present in the commercial PB sample that would otherwise migrate over to the PS domain causing plasticization, it is found that theTg(z) profile in PS next to PB is consistent with previous results. It is also demonstrated that these broad and asymmetric experimentally observedTg(z) profiles are not caused by the migration of low molecular weight chains across the interface by comparing samples made with two different poly(n‐butyl methacrylate) molecular weights.

 
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Award ID(s):
1709132 1151646
NSF-PAR ID:
10047116
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Macromolecular Chemistry and Physics
Volume:
219
Issue:
3
ISSN:
1022-1352
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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