ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
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 anionic polymerization of a variety of secondary alkyl crotonates and related monomers initiated by fluorenyllithium (complexed with tetrahydrofuran) in toluene at -78°C. is reported. No crystallinity could be developed in any of the samples, and nuclear magnetic resonance was uniformative about possible tacticity. The polymerization techniques were ineffective when applied to n-alkyl esters. Polymer was obtained from isopropyl cinnamate and N,N-dimethyl crotonamide, but not from isopropyl thiocrotonate or isopropyl 2-pentenoate. The physical properties of injectionmolded specimens of polymers of isopropyl, s-butyl and cyclohexyl crotonate were examined in some detail; the polymers exhibited a desirable combination of high service temperatures and good impact resistance for a vinyl homopolymer but were extremely difficult to mold. Poly(isopropyl crotonate) had a heat distortion temperature of 125°C. at 85 psi, a notched Izod impact of 2.4 ft.-lb./in. of notch, and a flexural modulus of 274,000 psi.
Additional Material:
3 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1967.070110916
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