Heat-resistant Polymer Matrix Rigid/Flexible Laminated Composites

Polymer matrix laminated composites are composed of organic polymer as the matrix and fiber or textile fabric(glass fiber,carbon fiber,etc.)as the reinforcement,which can combine the performance of polymer and fiber.Laminated composites are composed of matrix material and reinforcing material.According to the classification of polymer matrix,polymer matrix laminated composites can be divided into rigid laminated composites based on resin and flexible laminated composites based on rubber.Fiber reinforced laminated composites which have the advantages of light weight,high strength,good corrosion resistance,designability and low cost,are widely used in machinery manufacturing,aerospace and construction industry.It is currently popular enhancement laminated composites.As a new type of thermosets,polybenzoxazine(PBZ)not only has high heat resistance and flame resistance,but also shows excellent dimensional stability,low water absorption and excellent mechanical properties.In addition,polybenzoxazine has higher heat resistance than epoxy resin and can be compared with polyimide.But its cost is lower than polyimide.PBZ has high cost performance,and benzoxazine resin also has advantages in curing processing.The curing temperature of PBZ is lower than that of bismaleimide.Therefore,in view of high heat resistance and high cost-effective products of benzoxazine resin,and in combination with the high strength of the glass fiber,we prepared glass fiber reinforced silicon-containing benzoxazine resin rigid laminated composites.The glass transition temperature(Tg)of it was 286?.We also obtained high-power carbon fiber heating rigid laminated composites based on benzoxazine resin because carbon fiber can generate heat in the case of power.At the same time,we prepared carbon fiber heating flexible laminated composites based on silicone rubber in light of silicone rubber had great heat resistance and flexibility.It can be folded to use and enrich the type of carbon fiber heating equipment and expand the application area.The primary content of the study and the results are shown as follows:1.The benzoxazine monomer bearing alkoxysilane group was synthesized using bisphenol A,3-aminopropyltriethoxysilane and formaldehyde as raw materials.We dissolved the benzoxazine monomer in the solvent to impregnate the glass fiber cloth,then the glass fiber reinforced benzoxazine resin rigid laminated composites with high Tg were prepared.The thermal properties of the cured resin were studied by dynamic mechanical analysis(DMA).The cured resin exhibited high glass transition temperature(Tg),which reached up to 286?.Since the resin matrix itself had good heat resistance,the laminated composites also exhibited good heat resistance.The mechanical properties of the rigid laminated composites were also tested.Their tensile strength,flexural strength and impact strength reached up to 227.3MPa,587.5MPa and 86.1kJ/m2,respectively.The results showed that the rigid laminated composites had good mechanical properties.We also used scanning electron microscopy(SEM)to observe the fracture surface and found that the glass fiber covered with benzoxazine resin,indicating that the combination of both were well.2.The di-amine benzoxazine monomer was synthesized using 4,4-Diaminodiphenyl methane,phenol and formaldehyde as raw materials.We dissolved the benzoxazine monomer in the solvent to impregnate the glass fiber cloth,then we prepared benzoxazine resin-based high-power carbon fiber heating laminated composites.Dynamic mechanical analysis(DMA)and Thermogravimetric Analysis(TGA)were carried out to testify the thermal properties of cured benzoxazine resin.Benzoxazine resin exhibited good thermal property.The glass transition temperature(Tg)was 220?.The 5%and 10%weight loss temperatures(Tds and Td10)reached up to 331? and 380?,respectively,and char yield of the resin was 40%.The power of carbon fiber electro-thermal rigid laminated composites can reach the maximum power of 1700W which is the market similar products 3 to 5 times.The surface temperature reached the heat balance in 5 min.It also had the characteristics of rapid warming and cool with no power attenuation.3.The silicone rubber compounds were prepared using methyl vinyl silicone rubber(MVQ)as raw rubber,fumed silica as filler and 2,5-dimethyl-2,5-bis(t-butylperoxy)hexane as vulcanizing agent.Then,the silicone rubber compound,the glass fiber cloth and the carbon fiber paper were laminated together to prepare the carbon fiber electro-thermal flexible laminated composites based on silicone rubber.The tensile strength and tear strength of vulcanized silicone rubber respectively reached up to 8.58MPa and 18.35kN/m respectively,and its elongation at break reached up to 1331.63%.The laminated composites had good mechanical properties with excellent flexibility which can be folded to use.When the input voltage was 40V,the power of the flexible laminated composites was 11.5W,and the power density could reach 0.20W/cm2.It was found that the flexible laminated composites also had the characteristics of rapid warming and cooling with no power attenuation as the same as the rigid laminated composites.