Effects of side alkoxy groups on the arylacetylene unit on properties of Poly(silylene arylacetylene)s

A series of poly(dimethylsilylene arylacetylene)s with different side alkoxy groups on the arylacetylene unit (named as PSA-(AO) resins), including methoxy (MO), ethoxy (EO), pentyloxy (PO), and decyloxy (DO), were synthesized from corresponding disubstituted diethynylbenzene and dichlorodimethylsilane. The processability, heat resistance and mechanical properties, and the effects of side alkoxy groups were investigated. The results show the processability of PSA-(AO) resins is improved, while the flexural properties and heat resistance of the relative cured resins decrease with the increase in the length of side alkoxy groups. The flexural strength and degradation temperature of 5% weight loss for the cured PSA-(EO) resin with side ethoxy groups reach 20.8 MPa and 415℃, respectively.