Accession Number : AD0703909

Title :   MODELS OF A DEGRADING POLYMER NETWORK.

Descriptive Note : Technical rept.,

Corporate Author : PRINCETON UNIV N J FRICK CHEMICAL LAB

Personal Author(s) : Shaw,Montgomery T.

Report Date : MAR 1970

Pagination or Media Count : 29

Abstract : Regular, two and three dimensional networks of linear analogs to elastic polymeric chains were 'degraded' randomly in an attempt to establish a relationship between the force produced by a constantly strained network and the number of chain scissions. This behavior is important for the quantitative interpretation of chemical stress relaxation data. The models showed that the initial modulus of the three dimensional networks should vary as the number of crosslinkages (tetrafunctional) to the 4/3 power. The initial rate of decay of the relative force for random main chain cleavage was (in the limit of infinite network size) equal to twice the rate of decay of the relative number of chains between the crosslinkages. At high degrees of degradation (relative number of chains between crosslinkages equal to 1/e), the models indicated that the relative force would approach zero in the limit of infinite network size. The behavior of the models showed that the force decay of a degrading network is considerably more rapid than had been generally thought. (Author)

Descriptors :   (*ELASTOMERS, *CHEMICAL BONDS), ELASTIC PROPERTIES, POLYMERS, MATHEMATICAL MODELS, STRESSES

Subject Categories : Physical Chemistry
      Elastomers and Rubber

Distribution Statement : APPROVED FOR PUBLIC RELEASE