The Investigation on Effect of the Curing Temperature on the Properties of Poly(Silylene Arylacetylene)

ABSTRACT Poly(silylene arylacetylene) (PSA) resins serve as a heat‐resistant resin matrix and can be used for functional materials such as wave transmission and ablation materials. In this work, the relationship between the curing temperature and properties of a poly(dimethylsiliylene ethynylenephenyleneethynylene) (PSA‐M) resin was investigated. The curing degree of the cured PSA‐M resins was characterized by the acetylene groups content. The porosity, density, water uptake, mechanical properties, and thermal stability of the cured PSA‐M resins with various curing degrees were investigated. The results reveal that the properties of the cured PSA‐M resins change obviously as the curing temperature increases. With the curing temperature increasing, the density of the cured PSA‐M resins decreases a little and then obviously increases. The flexural strengths of cured PSA resins gradually decrease and then reach a stable value, while the flexural moduli first decrease slightly and then increase for the cured PSA‐M resins with the increase in the curing temperature. When the curing degree arrives at a certain extent, the coefficient of thermal expansion of the cured PSA‐M resins tends to remain stable from room temperature to 450°C.