Preparation And Performance Study Of Benzoxazine-Epoxy Resin Matrix High Temperature Resistance And Fireproof Composite

Benzoxazine resin is a new kind of phenolic resin, which has goood heat resistance and flame resistance and can be used without releasing small molecules. After curing benzoxazine and epoxy resin formed one mixed system, it has better high temperature resistance and mechanical properties, but does not meet the requirement of some applications, we can modify it by adding charring agent. In this paper, One kind of bisphenol-A type benzoxazine resin (BOZ) was synthesized by solvent-free method, co-curing it with bisphenol-A type epoxy resin (EP) and three kinds of charring agent such as red phosphorus (RP)、melamine (MA) and ammonium polyphosphate (APP), Carbon yield ratio and carbon layer structure of co-curing resin matrix was studied after them burned in high temperature flame. According this study to chose the best suitable resin to prepare the high temperature resistance and fire proof composites.Study on the resin matrix of high temperature resistance and fireproof composites:In this paper, One kind of bisphenol-A type benzoxazine resin (BOZ) was synthesized by solvent-free method, co-curing it with epoxy resin to study its curing characters. And added RP、MA and APP charring agents to prepare resin cast and test their fireproof properties. The molecular structure of this kind bisphenol-A type benzoxazine resin was characterized by Fourier Transform infrared spectroscopy(FTIR) and H Nuclear Magnetic Resonance(HNMR). By the use of TG we can measure it carbon yield ratio reach 50% under 1000℃.The co-curing reaction characteristics of BOZ with epoxy was investigated by DSC, the top temperature can reach 240℃;and its thermal properties was studied by TG-DTA, the results showed that the starting decomposition temperature was 310 ℃ and the top decomposition temperature was 670℃. The carbon yield ratio of matrix is 46.44% when 7% RP charring agent was added. The carbon yield ratio of matrix is 61.76% when 7% APP charring agent was added. Above all study we konw this two kinds of matrix were suitable to prepare the high temperature resistance and fire proof composites.Preparation and fireproof performance study of high temperature resistance and fireproof composites:In this paper two kinds of high temperature resistance and fire proof composites were successfully prepared, one is 7% RP charring agent was added and the other one is 7% APP charring agent was added. Carbon yield ratio and carbon layer structure of them was studied after them burned in high temperature flame by different times, according to these tests to measure their short-term and long-term fireproof properties. Study shows:Carbon yield ratio of these composite were studied after them burned in 1000℃ flame by 3 minutes, it was 24.43% when 7% RP charring agent was added and it was 27.79% when 7% APP charring agent was added, these number are both 10% higher than the composite without any charring agent added, so this two kinds of composites material both have a excellent property of short-term fireproof. By the same measure the carbon yield ratio of these composite were studied after them burned in 1000℃ flame by 15 minutes, it was 17.31% when 7% RP charring agent was added and it was 24.11% when 7% APP charring agent was added, these number are both 15～20% higher than the composite without any charring agent added, so this two kinds of composites material both have a excellent property of long-term fireproof.Preparation and fireproof performance study of CAM/BOZ/EP resin matrix high temperature resistance and fireproof composites:In order to make APP has lower hygroscopicity and better compatibility when it was added in polymer resin matrix, in this paper CAM was preparated. Study the relationships between reactant ratio、reaction concentration、temperature and the yield of the CAM. XPS was used to measure its elements characterized. Add the CAM carbon agent into BOZ/EP glue to preparate CAM/BOZ/EP resin castings and composites, and study the impact of CAM fire resistance of the material by burning experiments. Experimental results show that:when reactant ratio m (APP):m (aluminum sulfate) was 1:0.9, reaction temperature was 80℃, the reaction product was 15.97%, the concentration reaches a maximum yield of 58.95%.Compatibility with the polymer and CAM is improved, the carbon yield ratio of matrix is 68.83% when 5% CAM charring agent was added.,the composite material have a excellent property of both short-term and long-term fireproof when CAM was added. Carbon yield ratio of these composite were studied after them burned in 1000℃ flame by 3 minutes and 15 minutes, it was 30.24% and 25.82%, Carbon layer coated well on the glass fiber protective and composite structure remains intact and still have a certain strength, it has have a excellent property of fireproof.