ISSN:
0887-6266
Keywords:
Hooke numbers
;
tensile properties
;
semi-interpenetrating networks
;
molecular composites
;
fibers
;
liquid crystalline polymers
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Hooke numbers He ≡ σb/(E∊b) are calculated from published ultimate tensile strengths σb, tensile moduli E, and ultimate elongations ∊b. Data for common thermoplastics and natural fibers each follow a function He = [1 + (∊b/∊crit)ab]-1/b with a Hookean region I (He = 1) at ∊b ≪ ∊crit, a non-Hookean region III at ∊b ≫ crit, and a transition region II for ∊b ≈ ∊crit. Only non-Hookean regions III were found for semisimultaneous interpenetrating networks from polyisobutylene-polymethyl methacrylate, thermoplastic elastomers from segmented polyamide-polyethers, molecular composites from poly(p-phenylene benzobisthiazole) and poly[2,5(6)-benzimidazole], and three groups of various synthetic fibers. The Hooke numbers of lyotropic and thermotropic liquid-crystalline polymers vary with the heat treatment and depend on orientation angles for orientation angles greater than ca. 10°. Hooke numbers much greater than 1 are observed for highly stressed polymers. ©1995 John Wiley & Sons, Inc.
Additional Material:
10 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/polb.1995.090330611
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