| With the social and economic development, Scientific technologies advances insociety ,demand for paper and paper variety and performance become more intense. Widththe use of paper, according to different usage purposes, to give papers to the appropriaterequirements also increased. To meet the field of aerospace and high temperature applications,high temperature specialty research and development is imperative.To ensure thermal stability performance of special paper, Enhanced resin is required .The traditional high-temperature epoxy resin is hard to meet the needs, which requiressynthesis good high temperature resin for specialty paper bonding. Benzoxazine as a new typeof phenolic resin, not only has excellent thermal properties, flame resistance and electricalinsulation, and overcome the shortcomings of release of small molecules in formingcuring process of traditional phenolic resin, products has low porosity, near-zero shrinkage,thus causing the widespread interest in the study.In order to improve the mechanical properties of specialty paper, heat resistance andtoughness, flame retardant and other comprehensive performance, In this paper, methods ofmolecular design, and the third component copolymer resin blend were used. In this paper, theintroduction of the benzoxazine polymerizable groups such as A series of high heat resistancebenzoxazine intermediate with a molecular weight has been synthesised , and compared withtraditional small molecule-based benzoxazine intermediates ,benzoxazine with a molecularweight of its own, thus further solidifying , with more excellent toughness than smallmolecule-based benzoxazine , as paper-based composites reinforced resin, curing molding toform three-dimensional network structure, and successive point between the molecular chainlength and flexibility, to realize the full tangles of short fiber and packages,which will helpenhance paper strength and toughness of composites. Further with the epoxy resin copolymer,rubber modified blends the mechanical properties and toughness of specialty paper, andthrough the introduction of benzoxazine organic and / or inorganic flame retardant ingredientsPreparation of specialty paper.1. In this thesis, with bisphenol AF, bisphenol A, formaldehyde, MDA, diamine as rawmaterial ,three diamine bisphenol-type benzoxazine BOZ-AFMDA, BOZ-AMDA,BOZ-HDM has been synthesized, and by heating polymerization reaction of the benzoxazine.PBOZ-AFMDA has good overall performance, with 5% weight loss temperature of 480℃,700℃in nitrogen atmosphere, the residual carbon was 87.28%, the initial temperature ofintermediate thermal ring-opening polymerization is 177℃, exothermic peak temperature to 234℃. BOZ-AMDA system thermal performance in hot pursuit , a 5% weight losstemperature of post-curing resin was 350℃, 700℃in nitrogen atmosphere, the residualcarbon rate of 44%. The thermal ring-opening polymerization of the initial temperature of 209℃, exothermic peak temperature of 251℃. BOZ-AHDM cured resin derived poor thermalperformance of a 5% weight loss temperature was 150℃, 700℃in nitrogen atmosphere,the residual carbon was 30%.2. Series of synthetic Benzoxazine resin were adopted to impregnated enhanced sheet,the results show that the mechanical properties of paper sheet enhanced , the order ofenhancement from strong to weak :AFMDA, AMDA, AHDM, benzoxazine has a veryexcellent results to improve the physical strength of paper sheet, especially AFMDA system,AFMDA system based materials impregnated special paper, the tensile strength of up to7.42kN / m, tear strength up to 2707mN. Values of epoxy resin on the sheet enhancementsignificantly different to enhance the best is E44, E44 enhance the tensile strength of the sheet,tear, elongation up to 6.52 kN / m, 2964 mN, 2.19% . When the epoxy resin content is 30%,the best performance, the 700℃in nitrogen atmosphere, the residual carbon rate was28.3%.3. Improve toughness of the resin and paper-based materials with liquid rubber and thetoughness of the resin matrix significantly improved ,the toughness of the sheet also willimprove, but the heat-resistant of sheet and resin to vary on some extent. toughening effect.ofATBN system is better than CTBN .4. flame retardants and flame-retardant epoxy resins adopted with benzoxazine blend orcopolymer resin impregnated paper-based base paper, the results show that the benzoxazineresins containing halogen flame retardant AFMDA system is better at room temperature,limiting oxygen index of 27.1 %. Brominated epoxy resin not only own good flame resistanceof sheet (EC1750 system, limiting oxygen index up to 27.8%), while also maintaining themechanical properties of paper sheets. Common modification of epoxy resin flame retardantsheet has excellent overall performance, limiting oxygen index of 28.4, in nitrogenatmosphere 5% weight loss temperature of 300℃, 700℃when the residual carbon was72.9%.
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