【作者】 王海龙；

【导师】 施文芳；

【作者基本信息】 中国科学技术大学 ， 高分子化学与物理， 2009， 博士

【摘要】 由于高分子材料性能优良,从而得以迅速发展,大量取代传统材料,广泛应用于各个领域。但是大部分高分子材料易燃,在加热或者有充足氧气的情况下很容易着火并迅速燃烧,释放大量烟尘和有毒气体,污染环境,造成危害。目前市场上用于高分子材料阻燃为目的阻燃剂仍以卤素型阻燃剂为主,它们虽然阻燃效果好,但是在燃烧时释放卤化氢等有毒腐蚀性气体,会造成“二次灾害”。因此,近几年来,关于含磷阻燃有机化合物以及阻燃树脂的研究成为“热点”课题。本论文合成了新型磷酸酯环氧单体,超支化聚磷酸酯环氧树脂,超支化聚膦酸酯丙烯酸酯以及超支化聚磷酸酯多胺,分别作为阻燃树脂及其固化剂,并详细研究了它们的热/光固化行为、阻燃性能、热学性能等,具体研究内容提要如下:合成了五种磷酸酯环氧化合物,采用FTIR、¹H-NMR和³¹P-NMR对其分子结构进行了表征。将含磷的三官能团脂环族环氧单体TECP作为一种反应型阻燃剂应用于阳离子光固化体系,将其与商业化双官能单体UVR-6110混合固化,制备一系列阻燃样品。氧指数（LOI）测试表明,当TECP的添加量达到50%时,其氧指数由原来的21增加到27;动态力学性能测试表明,其软化温度和玻璃化温度分别由86℃和131℃下降到55℃和91℃;力学性能测试表明,其拉伸强度上升了11%。实时红外结果显示其为凝聚相阻燃机理。采用A₂+B₃法合成了超支化聚磷酸酯环氧树脂（E-HBPP）,将它与DGEBA以不同比例混合热固化制备一系列树脂样品。LOI测量表明,随着E-HBPP含量的增加,炭层膨胀程度随之增大,氧指数也随之增加。TGA和实时红外光谱的结果表明,磷酸酯在300℃左右降解生成焦磷酸,在固化膜的表面覆盖一层液膜,保护碳层不被继续氧化。因此,含磷量越高,同时成炭量也越高。DMTA结果表明,E-HBPP和环氧树脂体系具有良好的相容性,且固化膜的交联密度和玻璃化转变温度均随E-HBPP含量的增加而降低;同时,当E-HBPP加入量小于20%时,可以有效地改善环氧体系的机械性能。采用A₂+B₃合成途径,以无水哌嗪和三官能度丙烯酸化磷酸酯（TAEP）为原料,通过迈克尔加成反应,制备了超支化聚磷酸酯多胺（HBPPA）。将HBPPA作为多官能团固化剂应用于双酚A环氧体系,DMTA结果表明以HBPPA固化的环氧树脂,其玻璃化转变温度有所降低。使用热重分析和LOI测定固化物的热性能和阻燃性能,结果发现由于聚合物结构中HBPPA的复合,其整体热稳定性在高温时得到了提高,氧指数亦有显著上升,当全部使用HBPPA作为固化剂时,LOI值可以达到31。采用A₂+B₃方法,以胺乙基哌嗪和二官能度丙烯酸化膦酸酯（DABP）为原料,合成超支化聚膦酸酯丙烯酸酯（HBPA）,将它与单体DABP以不同比例混合光固化制备一系列树脂样品。光聚合动力学研究表明,其双键转化率随着HBPA含量的增加而增加,纯HBPA的转化率达到81.0%。LOI测量表明,随着HBPA含量的增加,炭层膨胀程度随之增大,氧指数变化范围为36～39。TGA和实时红外光谱的结果表明,固化膜的热降解速率主要受交联密度和含磷量两个因素的影响,而最终成碳量随着DABP含量的增加而增加。DMTA结果表明,HBPA和单体树脂具有良好的相容性,且固化膜的交联密度和玻璃化转变温度均随HBPA含量的增加而降低。更多还原

【Abstract】 Over the last few decades the replacement of conventional materials by synthetic polymeric materials has increased dramatically owing to their versatility,low density, and some other novel properties.Although the polymers have become widely accepted in various areas,many of them are extremely flammable and,in presence of sufficient heat and oxygen,burn easily and rapidly.The problem is not only the destruction of the materials but the smoke and toxic gases generated which are the main causes of hazards in a fire.Although in the last few years there has been an increase of heteroelements used in flame retardants,the commercial market is still dominated by the compounds based on halogens.These compounds present exceptional efficiency,interfering with the reactions responsible of flame propagation.However,during the combustion they release toxic and corrosive gases.Therefore,the interest has increased in the research of halogen-free based flame retardants,such as phosphorus flame retardants,which are more environmentally friendly and less aggressive in a fire.The present thesis is aimed on the development of new environmentally flame retardant materials.The detailed outline is elaborated as follows:Five phosphate epoxy monomers were synthesized and the molecular structures were confirmed by FTIR,¹H-NMR and ³¹P-NMR spectroscopic analysis.The phosphorus-containing trifunctional cycloaliphatic epoxide resin, tri（3,4-epoxycyclohexylmethyl） phosphate（TECP） was used as a reactive-type flame retardant for cationically UV curing coatings.A series of flame retardant formulations by incorporating into a commercial difunctional cycloaliphatic epoxide resin, CYRACURETM UVR-6110,were prepared,and exposed to a medium pressure lamp to form the cured films under the presence of diaryliodonium hexafluorophosphate salt as a cationic photoinitiator.Their flame retardancy examined by the limiting oxygen index showed the improvement up to 27 for 50 wt%TECP addition compared with 21 for pure UVR-6110.The T_s and T_g decreased from 86℃and 131℃to 55℃ and 91℃,respectively,by using dynamic mechanical thermal analysis,whereas the tensile strength showed a slight increase（11%） with 50 wt%TECP addition.The thermogravimetric analysis（TGA） and real time FTIR measurement demonstrated the condensed-phase flame retardant mechanism.A novel epoxy-terminated hyperbranched polyphosphate（E-HBPP） was synthesized by employing an A₂+B₃ polycondensation and characterized by FTIR,¹H NMR and GPC.E-HBPP was used as a reactive-type flame retardant for Diglycidyl ether of bisphenol-A/ m-phenylene diamine（DGEBA/mPDA） system.A series of flame retardant resins were prepared and their flame retardancy was monitored by the limiting oxygen index.The results showed that the LOI value of the cured samples and the degree of expansion of the formed char after burning increased along with the E-HBPP content.Their thermal degradation behaviors were investigated by thermogravimetric analysis and in suit FTIR and showed that the phosphate group of E-HBPP first degraded to form poly（phosphoric acid）s at around 300℃,which had a major contribution to form the compact char to protect the sample from further degradation.The dynamic mechanical thermal properties were studied by dynamic mechanical thermal analysis（DMTA） and the results showed a good miscibility between E-HBPP and DGEBA.The mechanical properties of the cured films were also investigated.Less than 20%E-HBPP addition improved both the tensile strength and elongation at break.Through Michael addition from piperazine as an A₂ monomer and tri（acryloyloxyethyl） phosphate（TAEP） as a B₃ monomer,a novel hyperbranched polyphosphate amine（HBPPA） was synthesized via the "A₂+B₃" approach.HBPPA was used as a multifunctional curing agent for bisphenol A epoxy resin.Dynamic mechanical thermal analysis showed the decrease of the glass transition temperature. The thermal degradation properties and flame retardancy were investigated by thermogravimetric analysis（TGA） and limiting oxygen index（LOI）.The obtained results showed that the incorporation of HBPPA into bisphenol-A epoxy resin increased its thermostability and char yield during the decomposition by raising the second stage decomposition temperature.The LOI value significantly increased with the addition of HBPPA.A novel hyperbranched polyphosphonate acrylate（ttBPA）,used as a reactive-type flame retardant in UV-curable systems,was successfully synthesized by the reaction of di（acryloyloxyethyl） benzenephosphonate（DABP） with N-（2-aminoethyl-） piperazine,and characterized by FTIR,¹H NMR and GPC measurements.HBPA was blended with DABP as a monomer in different ratios to obtain a series of flame retardant resins.Their maximum photopolymerization rates(R_p^max) and final unsaturation conversion（P^f） in the cured films at the presence of a photofragmenting initiator were investigated.The results showed that the P^f increased along with HBPA content and the pure HBPA has the maximum value of 81.0%in the photo-DSC analysis.Their flame retardancy was monitored by the limiting oxygen index（LOI）, and showed that the UV cured films greatly expanded when burning,and the degree of expansion increased along with HBPA content.However,the LOI values varied from 36.0 to 39.0,which can be ascribed to the condensed phase mechanism.Their thermal degradation behaviors were investigated by thermogravimetric analysis and in situ FTIR spectroscopy,and showed that the phosphonate group of HBPA first degraded to form poly（phosphoric acid）s at around 300℃,which had a major contribution to form the compact char to protect the sample from further degradation. The dynamic mechanical thermal properties were studied by dynamic mechanical thermal analysis and showed a good miscibility between HBPA and DABR The crosslinking density and T_g of the cured films decreased along with the content of HBPA in the blends.更多还原