The main advantage of silicon nitrogen rubber is that it has excellent thermal stability, does not decompose at 430 ～ 480 ℃, and some can even withstand high temperatures above 500 ℃. The outstanding weakness of silicone rubber is the poor hydrolytic stability, which was once considered to have no future. Later, it was found that polymers introduced with cyclodisilazane in the main chain had good thermal stability. Cyclic disilazane-containing elastomers modified with silarylene do not lose weight when heated to 425 ° C in air, and the weight loss is only 10% at 570 ° C, and has good hydrolysis stability.