ISSN:
0032-3888
Keywords:
Chemistry
;
Chemical Engineering
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
The mechanical and optical properties have been examined of a series of polyurethane-polystyrene two-phase systems produced by simultaneous polymerization. Torsion pendulum data show two separate glass transitions which are essentially those of the constituent homopolymers. Thus these systems do not from true interpenetrating networks. Phase inversion from a continuous polyurethane to a continuous polystyrene phase occurred at the relatively low styrene concentration of 20 to 25%. Measurements of the stress-optical coefficients supported this finding. When polystyrene formed the continuous phase, straining produced softening at strains below about 15 percent. Birefringence measurements indicated that the rubbery polyurethane domains did not orient in these compositions. The stress-optical coefficients showed no time dependence. The strain-optical coefficients decreased with increasing temperature.
Additional Material:
7 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pen.760150504
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