Preparation Of Silane Benzoxazine And Its Application In Composites

The work in this paper included:1.Benzoxazine was synthesized by BPA,paraformaldehyde and KH-550,resulting PB by curing,then resulting PBS by curing with the modified silica. The chemical structure of b-BZ was characterized by FT-IR,1H-NMR.The curing characteristics was studied by DSC and the thermostability was studied by TG. The results show that:in N2, ring opening polymerization of b-BZ was 181℃.To PB,temperature of 5% weight loss was 302℃, temperature of 10% weight loss was 375℃ and carbon residue was 53% in 800℃;to PBS,temperature of 5% weight loss was 316℃, temperature of 10% weight loss was 407℃, and carbon residue was 59% in 800℃.The SEM image of polymers shows that bisphenol siloxane benzoxazine with the modified silica has good compatibility and ductibility.2. Two kinds of the modified silane coupling agent was synthesized by choosing appropriate raw material and study its application in lignin and nylon-6 Composites The p-BZ was synthesized by using phenol, paraformaldehyde and KH-550 in the ratio of 1:2:;the c-BZ was synthesized by using cardanol, paraformaldehyde and KH-550 in the ratio of 1:2:1. The p-BZ and c-BZ were first blended with a certain quality of lignin, and then mixed with nylon-6, resulting nylon-6/phenol benzoxazine-type modified silane coupling agent/lignin composite(p-BZN) and nylon-6/cardanol benzoxazine-type modified silane coupling agent/lignin composite(c-BZN). TG analysis shows:to p-BZ, temperature of 5% weight loss was 342℃, temperature of 10% weight loss was 364℃, and carbon residue was 19% in 800℃;to c-BZ, temperature of 5% weight loss was 345℃, temperature of 10% weight loss was 367℃, and carbon residue was 16%;to nylon-6, temperature of 5% weight loss was 387℃, temperature of 10% weight loss was 404℃, and carbon residue was 2%. At room temperature,tensile strength of p-BZN is 39.92MPa, elongation at break was 7.59%, and the Izod impact strength was 2.80KJ/m3, Charpy impact strength was 3.43 KJ/m3; tensile strength of c-BZN was 42.83MPa, elongation at break was 8.14%, and the Izod impact strength of 2.93 KJ/m3, Charpy impact strength of 3.95 KJ/m3.3. We had a research on thermal degradation kinetics of p-BZN and c-BZN. Using Kissinger maximum weight loss rate method of thermal degradation activation energy is 144.16KJ/mol and 149.49KJ/mol.