Simon, E. and Thomas, F. W. (to Lockheed Aircraft Company), U. S. Patent 2,577,279, December 4, 1951; 2,577,280, December 4, 1951; 2,577,281, December 4, 1961; 2,591,884, April 8, 1952; 2,602,783, July 8, 1952; 2,634,244, April 7, 1953; 2,642,403, June 16, 1953.
3.
Detrick, S R. and Barthel, E (to DuPont), U. S. Patent 2,787,601, April 2, 1957.
4.
Barchet, E. (to DuPont), U. S. Patent 2,788,335, April 9, 1057
5.
Mitchell, A. (to DuPont), U S Patent 2,814,600, November 26, 1957
6.
Young, D. M , Hostettler, F , Shriver, L. C and Mc-Laughlin, R. W., "Polyesters from Lactones ", Division of Pamt, Plastics, and Printing Ink Chemistry, 130th Meetmg ACS, Atlantic City, N J., September, 1956.
7.
Ibid , "Polyurethanes from Lactone Polyesters".
8.
Young, D M. and Hostettler, F. (to Union Carbide Corporation), U S Patent 2,878,236, March 17, 1959; 2,890,208, June 9, 1959, 2,933,478, April 19, 1960; 2,990,379, June 27, 1961, 3,051,687, August 28, 1962.
9.
Hostettler, F. and Young, D. M. (to Union Carbide Corporation) U. S. Patent 3,169,945, February 16, 1965, 3,186,971, June 1, 1965.
10.
Smith, C. H., Industrial Engineering Chemistry, Product Research and Development, 2, 27 (1963)
11.
Davis, S., McClellan, J. M. and Frisch, K. C , Isocyanate Symposium, Soc. of Plastics Engineers , Minneapolis, Minn , October 1957 .
12.
Backus, J K , Barnard, D. L., Darr, W. C. and Saunders, J. H., J. Appl. Poly Science, 12, 1053 (1968).