DEVELOPMENT OF NEW POLYMERS FOR AIRCRAFT APPLICATION
Abstract
Studies of the curing action of organic agents on chloroprene ( I)- methacrylic acid (II) copolymers resulted in the discovery of 6-amino-2-mercaptobenzothiazole (AMBT) and p-aminophenol, which produced films with a tensile strength of 4000 psi after a 14-day cure. Substitution of pure benzidene for the technical grade increased the tensile strength more than 600 psi. Diamines displayed a prolonged curing action; the tensile strength after 100 days was higher than that after 14 days. The nature of the diamine cure and the possibility of amide formation were studied. The rate of room-temperature cure was largely a function of the rate of lacquer solvent removal. Ketones generally appeared to remain longer in copolymer films due to association with the carboxyl groups. Monomer relative reactivity ratios for I(r sub I) and II(r sub II) were determined at 30 deg C. In emulsion, R sub I = 5.9 + or - 0.5 and R sub II = 0.14 + or - 0.05; in bulk, r sub I - 1.4 + or - 0.5 and r sub II = 0.16 + or - 0.07. Low-temperature properties were examined for I-methacrylamide, I-acrylonitrile, and I-acrylic acid copolymers; results with I-II, rubber, and neoprene were included for comparison. The results indicated the poor low-temperature flexibility of the copolymers as comparaed to neoprene. The I-II and I-acrylonitrile copolymers exhibited inferior dynamic flexibility but slightly superior flexibility under static stress.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 30, 1953
- Accession Number
- AD0012372
Entities
People
- Albert Haefner
- Henno Keskkula
- John Adams