本文選題：羥基改性PBZ~o + 苯并唑類聚合物與纖維��； 參考：《浙江工業(yè)大學(xué)》2017年碩士論文

【摘要】：苯并唑類聚合物(PBZ)是一雜環(huán)類的聚合物,分二唑與單唑兩大類。二唑類以聚對苯撐苯并雙VA唑(PBO)為著名,包括雙噻唑(PBT)和雙咪唑(PBI),其纖維具有高強、高模、耐高溫及阻燃等優(yōu)異特性,已展現(xiàn)巨大的應(yīng)用前景。而改性PBZ的單體尤其是AB型單體研究漸漸成為目前的研究熱點,用它聚合紡絲制備的改性PBZ纖維,著重于改善原纖維存在表面相對惰性,耐壓縮性能及紫外穩(wěn)定性能不足的同時,避免原有工藝帶來的問題。本文選擇PBZ最簡結(jié)構(gòu)的單唑類聚合物(PBZo)并以羥基改性為目標(biāo),通過AB型改性PBZo新單體:聚6-羥基-2,5-苯并咪唑(HPBIo)和聚6-羥基-2,5-苯并VA唑(HPBOo)的設(shè)計與創(chuàng)制,探索其應(yīng)用于均縮聚或與PBO單體共縮聚制備羥基和咪唑綜合改性PBO樹脂與纖維的效果,以提高PBO纖維的軸向抗壓能力以及復(fù)合粘結(jié)性能。研究內(nèi)容主要包括以下4個方面:首先系統(tǒng)研究了AB型HPBIo單體的關(guān)鍵中間體4-氨基-2-羥基-5-硝基苯甲酸(AHNA)的兩種合成技術(shù):以對氨基水楊酸(ASA)為原料,經(jīng)酰胺化、硝化與水解反應(yīng)三步法合成AHNA,總收率56.3%,純度99.21%。以對氨基水楊酸甲酯(MAHB)為起始原料,經(jīng)硝化和水解兩步合成AHNA,總收率66.6%,純度98.22%。在此基礎(chǔ)上,再以AHNA為原料,經(jīng)還原反應(yīng)合成AB型HPBIo單體4,5-二氨基-2-羥基苯甲酸(DAHBA),并對水合肼還原工藝進(jìn)行條件優(yōu)化后,收率55.3%,純度98.84%。然后,研究以ASA為原料,經(jīng)重氮偶合與還原反應(yīng)合成DAHBA,并對偶合與還原工藝條件進(jìn)行條件優(yōu)化,獲得總收率為39.4%,純度為99.04%。同時,以成功合成DAHBA的新路線作參考,探索研究以2,4-二羥基苯甲酸為原料,經(jīng)重氮偶合反應(yīng),還原反應(yīng)兩步合成羥基改性HPBOo纖維單體2,4-二羥基-5-氨基苯甲酸(DHABA),總收率為34.5%,純度為95.12%。最后,以DAHBA與AB型PBO單體4-(5-氨基-6-羥基苯并VA唑-2-基)苯甲酸銨(ABAA)為單體原料,探索經(jīng)共聚制備羥基與咪唑綜合改性PBO的聚6-羥基-2,5-苯并咪唑/對苯撐苯并雙VA唑(HI-PBO)樹脂纖維,熱分解溫度達(dá)到552℃,結(jié)果表明:HI-PBO分子量越大其耐熱溫度就越高。本文合成的若干中間體以及新單體的分子結(jié)構(gòu)均經(jīng)過IR,NMR,MS等定性分析確認(rèn)。本研究具備新穎性,并具有良好發(fā)展的工業(yè)化前景,可為推動我國改性PBO纖維的發(fā)展提供技術(shù)支持。
[Abstract]:Benzoxazole polymer (PBZ) is a heterocyclic polymer, which is divided into two groups: diazole and monazole. Diazoles are famous for their poly (p-phenylene benzobis VA) (PBO), including dithiazolium (PBT) and diimidazolium (PBI). Their fibers have excellent properties such as high strength, high modulus, high temperature resistance and flame retardancy, and have shown great application prospects. However, the study of modified PBZ monomers, especially AB monomers, has gradually become a hot research topic. The modified PBZ fibers prepared by polymerization spinning with the modified PBZ fibers focus on improving the relative inertia of the surface of the original fibers. Compression resistance and UV stability are inadequate, while avoiding problems caused by the original process. In this paper, the simple structure of PBZ, monazole polymer (PBZoo), was selected and the design and creation of new PBZo monomers modified by AB type: poly6-hydroxy-2-benzimidazole-5-benzimidazolium (HPBIoand) and poly (6-hydroxy-2butazole) (HPBOo) were carried out. The results of homopolycondensation or co-condensation with PBO monomers in the preparation of hydroxyl and imidazole modified PBO resins and fibers were explored in order to improve the axial compressive resistance and the composite bonding properties of PBO fibers. The main contents of the study are as follows: firstly, two synthetic techniques of the key intermediate of AB type HPBIo, 4- amino-2-hydroxy-5-nitrobenzoic acid (AHNA), were studied systematically, which were amidation of 4-aminosalicylic acid (ASAA). AHNA was synthesized by three steps of nitrification and hydrolysis. The total yield was 56.3 and the purity was 99.21. AHNA was synthesized from p-aminosalicylic acid methyl ester (MAHBB) by nitration and hydrolysis with a total yield of 66.6% and purity of 98.22%. On this basis, AB type HPBIo was synthesized by reduction reaction using AHNA as raw material. After optimization of the reduction process of hydrazine hydrate, the yield was 55.3 and the purity was 98.84. Then, DAHBA was synthesized by diazo coupling and reduction reaction using ASA as raw material, and the conditions of coupling and reduction were optimized. The total yield was 39.4 and the purity was 99.04. At the same time, with the reference of the new route of successful synthesis of DAHBA, the diazo coupling reaction was studied by diazo coupling reaction with 2o 4-dihydroxybenzoic acid as raw material. The hydroxyl modified HPBOo fiber monomer 2o 4-dihydroxy-5-aminobenzoic acid (DHABA) was synthesized by two-step reduction reaction. The overall yield was 34.5and the purity was 95.12. Finally, the poly (6-hydroxy-2-butadiazole-5-benzobisole HI-PBO) resin fiber modified by hydroxyl and imidazole was prepared by copolymerization of 4-Amino-6-hydroxybenzo-6-hydroxybutazol-2-yl benzoic acid ammonium benzoate (ABAAA) as the monomer of DAHBA and AB type PBO monomers, and the synthesis of poly6-hydroxy-2-benzobisazole-5-benzimidazole / p-benzobisole HI-PBO resin fiber was investigated through the copolymerization of hydroxyl and imidazole. The thermal decomposition temperature reached 552 鈩，

本文編號：2034658