STRUCTURE EFFECTS ON THE SOL FRACTION-DOSE RELATIONSHIP IN RADIATION CROSSLINKING OF POLYMERS

The structure effects of polymers on the relationship between sol fraction and radiation dose arediscussed in detail. In consideration of the deviation of experimental results from Charlesby-Pin-ner's and Chen-Liu-Tang's expressions relating sol fraction to radiation dose, we introduced an ex-ponent βconcerned with the structure and property parameters of a polymer (glass transition tem-perature T_g and molecular internal rotating steric factor δ) and assumed that the fracture density isproportional to R~β(R is radiation dose). Thus, a general expression, formula (9), relating solfraction to radiation dose is derived. When β=1 andβ=0.5, this expression is reduced to the above-said two expressions. Us-ing this general expression, the experimental data of a number of polymers are treated. It is shownthat the expression is in good agreement with the experimental results, βvalue is in the range of 0. 5 to1.0.

STRUCTURE EFFECTS ON THE SOL FRACTION-DOSE RELATIONSHIP IN RADIATION CROSSLINKING OF POLYMERS*

 The structure effects of polymers on the relationship between sol fraction and radiation dose arediscussed in detail. In consideration of the deviation of experimental results from Charlesby-Pin-ner's and Chen-Liu-Tang's expressions relating sol fraction to radiation dose, we introduced an ex-ponent β concerned with the structure and property parameters of a polymer (glass transition tem-perature T_g and molecular internal rotating steric factor δ) and assumed that the fracture density isproportional to R^β(R is radiation dose).Thus,a general expression,formula (9),relating sol fraction to radiation dose is derived.When β=1 and β=0.5,this expression is reduced to the abpve-said two expressions,Using this general expression,the experimental data of a number of polymers are treated.It is shown that the expression is in good agreement with the experimental results,β value is in the range of 0.5 to 1.0.