【作者】 荔栓红；

【导师】 王兴亚；

【作者基本信息】 西北师范大学 ， 高分子化学与物理， 2009， 博士

【摘要】 材料是科学和工业发展的基础,研究与开发高性能与特种功能,具有较大实用价值的新型材料已成为当今材料科学领域的研究热点。近年来,随着高分子材料应用范围的迅速扩大,对高分子材料的耐热性提出了越来越高的要求,聚酰亚胺类聚合物以其优异的耐热性能而受到普遍关注,特别是N-取代马来酰亚胺类聚合物,二十世纪八十年代中期以来已成为一个研究热点。聚合物热稳定性包括两个方面,其一是与形变、比容、强度等物理变化有关的耐热性,这种变化是大分子运动或链运动所引起的,常用热形变温度、软化点、玻璃化温度、熔点来表示;其二是与分解、降解、解聚等化学变化有关的热稳定性,以热分解温度、热失重温度、耐化学性等来表征。聚合物耐热性是由其结构决定的。提高聚合物耐热性可通过三个途径:引入极性基团、芳杂环以及进行交联。共混和复合也是提高聚合物材料耐热性的有效途径。在乙烯基单体聚合物中引入N-取代马来酰亚胺（英文缩写“NPMI”）、马来酸酐（英文缩写“MA”）等,可有效提高其耐热性,制成所谓的耐热通用树脂,这是一个十分有价值的研究方向。本文首先采用悬浮聚合工艺合成了苯乙烯-丙烯腈- N-取代马来酰亚胺（英文缩写“St-AN-NPMI”）三元共聚物SMIA;确定了悬浮聚合合成St-AN-NPMI三元共聚物SMIA聚合反应上限温度为75℃;得到了NPMI、St单体配比与三元共聚物SMIA玻璃化温度Tg之间的关系: Tg_{SMIA- NPMI}=105.3+1.27*NPMI（%） Tg_SMIA-St= -0.0743^*[St（%）]²+6.5714*St（%）-15.4同时,得到了NPMI、St单体配比与三元共聚物SMIA维卡软化温度Vicat之间的关系: Vicat（SMIA- NPMI）=98.357+1.3286*NPMI（%） Vicat（SMIA-St）= -1.514*St（%）+197.07也得到了St单体配比与三元共聚物SMIA熔体流动速率MI之间的关系: MI_SMIA-St= 0.69*St（%）-24.21并确定了合成St-AN-NPMI三元共聚物SMIA所用NPMI的质量规格:纯度> 97%;第二,进行了SMIA共聚反应的中试研究。确定2M3聚合釜进行SMIA共聚反应中试放大试验聚合釜搅拌浆型为斜浆,搅拌转速170转/分钟,中试放大准则为单位体积功率Pv,依次制定出了2M3聚合釜进行SMIA共聚反应的温度控制方案,并成功实施;在2M3聚合釜中成功进行SMIA共聚反应中试放大试验,并利用2M3聚合釜合成的SMIA共聚物,在1500吨/年的ABS树脂生产线上制备出了N-I、N-Ⅱ两个牌号的耐热ABS树脂。第三,进行了SMIA共聚反应的工业试验研究。通过研究发现合成SMIA共聚物的聚合反应,反应初期单位时间转化率增量最大,为26.6%;在工业试验装置30M3聚合釜中合成SMIA共聚物,理论上反应初期聚合釜内部的温度与夹套换热水的温度差为35.64℃,聚合反应温度为70℃时,所需夹套换热水的温度只要低于34.36℃即可满足要求;在30M3聚合釜中成功进行7批合成SMIA共聚物的工业试验,工业试验结果重现性、稳定性良好;利用30M3聚合釜工业试验合成的SMIA共聚物,在兰州石化合成橡胶厂ABS车间工业装置上生产出了N-I、N-Ⅱ两个牌号的耐热ABS树脂,并进行了推广应用。第四,对St-NPMI二元共聚物SMI的合成技术进行了研究。发现采用常规悬浮聚合方法合成St-NPMI二元共聚物SMI,组成不均一,St配方量在55份以上时,SMI的差动热分析表现出两个Tg峰;采用聚合反应后期补加AN的常规悬浮聚合方法合成了St-NPMI二元共聚物SMI,在较大St配方量范围,SMI的差动热分析也表现出两个Tg峰;采用常规乳液聚合方法合成了St-NPMI二元共聚物SMI, St配方量在65份以上时,SMI的差动热分析同样表现出两个Tg峰。作者首创悬浮溶液聚合方法,并采用该方法合成了St-NPMI二元共聚物SMI,在较大St配方量范围,SMI组成均一,差动热分析只表现出一个Tg峰;在此基础上采用正交试验法,确定了悬浮溶液聚合法合成St-NPMI二元共聚物SMI的最佳配方及工艺条件,并采用悬浮溶液聚合法合成的St-NPMI二元共聚物SMI,制备出了性能良好的耐热ABS树脂,其维卡软化点最高可达154℃。第五,研究了系列乳液聚合技术合成SMIA树脂的方法。（1）采用常规乳液聚合法合成SMIA树脂,能完成反应,但乳液放置10小时变粉色,得到的聚合物经凝聚后干燥,产物呈现出粉红色的外观;（2）采用常规乳液聚合法、油溶性热分解引发剂合成SMIA乳液,聚合反应能完成,但反应过程中产生了较高比例（1.0³.0%）的块状析出物,乳液产物不变色;（3）采用预乳化工艺下油溶性热分解引发剂合成SMIA乳液,聚合反应能顺利完成,体系稳定性有了较大改善,反应过程中析出物减少,乳液产物不变色;（4）首创有初级乳液的预乳化工艺下油溶性热分解引发剂合成SMIA乳液的乳液聚合方法,聚合反应极易控制,反应过程非常稳定,聚合结束基本无析出物产生,乳液产物不变色。在此基础上对有初级乳液的预乳化油溶性热分解引发剂合成SMIA乳液工艺的反应温度、凝聚和熟化温度等工艺条件进行了优化。第六,分析了不同NPMI配方量的SMIA共聚物在不同温度（190、200、210、230℃）、不同剪切速率（10¹03 s-1）下的流变性能。（1）在相同的NPMI配方量（0～20%）及相同的温度（190～230℃）下,共聚物熔体的剪切应力随剪切速率的增大而增加,且二者的对数近似为线性关系,可用线性方程表示,其斜率即为熔体的非牛顿指数n;共聚物熔体都是假塑性流体,各自的非牛顿指数因温度而异且有一定的分布范围;在相同的NPMI配方量及相同的剪切速率下,剪切应力随温度的升高而减小,剪切应力对数减小的幅度和温度升高的幅度基本呈线形关系。在相同温度与相同剪切速率下,剪切应力随NPMI配方量的增加而增大,剪切应力对数增大的幅度随NPMI配方量的增加不尽相同。（2）在相同的NPMI配方量（0～20%）及相同的温度（190～230℃）下,表观粘度随剪切速率的增大而减小,且二者的对数近似为线性关系,其斜率n-1因温度而异并有一定的分布范围;在相同的NPMI配方量及相同的剪切速率下,表观粘度随温度的升高而减小,表观粘度对数减小的幅度和温度升高的幅度基本呈线形关系。在相同温度与相同剪切速率下,表观粘度随NPMI配方量的增加而增大,表观粘度对数增大的幅度随NPMI配方量的增加不尽相同。（3）在相同的NPMI配方量及相同的剪切速率下,表观粘度随温度的增加而减小,且1000/T与表观粘度对数近似为线性关系,其斜率就是表观流动活化能,表观流动活化能随NPMI配方量增加而变大。更多还原

【Abstract】 Material is a foundation of the development of science and industry. The research of novel material with high-performance and functions become a hot point in material science field recently. With the polymeric material widely used, the performance of heat-resistance is paid more and more attention. For its outstanding heat-resistance polyimide resin, especially N-phenyl maleimide (NPMI) is the best choice and has been studied from 80’s twenty century.The thermal stability of polymer material can be understood from two directions. One is revolves in the physical changes such as deformation, specific volume, strength. These changes usually induced by macromolecule and/or chain movement are testified with heat deformation temperature, softening point, glass transition temperature (Tg) and melt point. Another one is the chemical changes, for example, material decomposition, degradation, depolymerization which are demonstrated by decomposition temperature, weight loss temperature and solvent-resistance.The heat-resistance of polymer determined by its own molecular structure can be improved through three methods: The introduction of polarity groups and aromatic ring structure to the main chain or crosslinking; the compounding or blending; grafting NPMI, maleic anhydride to vinyl polymers. The later is the most promising method in producing high heat-resistance polymer material. (1)In this paper, NPMI-g-styrene(St)-acrylonitrile(AN) (SMIA) copolymer is synthesized by suspension polymerization. The upper limit temperature in the reaction is defined at 75℃. The following equations show the relation between Tg and the ratio of NPMI to St. Tg(SMIA- NPMI)=105.3+1.27*NPMI(%) Tg(SMIA-St)= -0.0743*[St(%)]2+6.5714*St(%)-15.4The following equations show the relation between the Vicat softening point and the ratio of NPMI to St. Vicat(SMIA- NPMI)=98.357+1.3286*NPMI(%) Vicat(SMIA-St)= -1.514*St(%)+197.07The following equation shows the relation between the melt index(MI) and the ratio of NPMI to St. MI(SMIA-St)= 0.69*St(%)-24.21 The purity of NPMI> 97%.(2)T he pilot test of SMIA copolymerization was conducted. The propeller type was pitched-blade turbine and the speed was at 160, 170 r/min. Amplification test criteria was defined at power in volume Pv. The temperature control method was determined. The copolymer SMIA was successfully carried out in pilot test and two brands of ABS products(N-I and N-II) were produced in 1500 t/a industry production line.(3)Industrial pilot test of SMIA copolymerization was carried out. During the study, it is found that the conversion arrived up to 26.6% in the initial unit reaction time. Theoretically, the initial reacting temperature is 36℃, higher than that of internal jacket water. So when the polymerization temperature is 70℃, the water temperature in internal jacket is only required about 34℃. In 30m3 reactor, seven batches of copolymer SMIA were produced. The N-I、N-II were produced and acquired application.(4) The synthetical technology of St-NPMI (SMI) was studied. By using conventional suspension polymerization, when the content of St is higher than 55%, there are two Tg peak in differential scanning calorimetry(DSC) curve. Adopting the method in which adding AN during the later reaction state and varying St content in a wider scope, two Tg peak also appeared clearly. When the content of St is up to 65%, two Tg peak also can be appeared.In this paper, SMI firstly synthesized used by suspension-solution polymerization. At a wide varying scope of St content, the content of monomers in SMI is even and homogeneous, for only one Tg peak appeared in the DSC curve. Based on orthogonal test method, the optimized recipe and reacting conditions were determined. The obtained softening point of ABS is 154℃.(5) The polymerization method for SMIA is systematically studied. a. SMIA is prepared by using conventional polymerization method. The emulsion system is stable. However, the colour of the emulsion turns to pink in static state for 10h. After drying the polymer, it is pink.b. SMIA emulsion is prepared with organic initiator by conventional process. The reaction could be conduct successfully, but some agglomeration could be produced (1.0~3.0%). The colour of the emulsion unvaried.c. Basing on pre-emulsification process and using organic initiator, SMIA emulsion is obtained. The reaction is successful and the system stability of the emulsion is highly enhanced. During the reacting, the little agglomeration is produced and the colour is good.d. The above polymerization method is easily controlled and the reacting is extremely stable. The agglomeration is very few. The reacting process is further optimized in the reacting temperature, agglomerating process and other aspects.(6)The rheological properties of SMIA with different content NPMI were investigated at different temperature (190, 200, 210, 230℃) and different shear rate(10-103 s-1). a. When the content of NPMI and the temperature remain the same, the copolymer melt shear stress climbs up with the increase of the shear rate, and the logarithms of them exhibit approximately linear relationship that can be stimulated via linear equations. The slope of the linear is the non-Newton melt index n. The copolymer melts are pseudoplastic fluid, and the non-Newton index varies due to temperature varies at a certain range. At the NPMI content and shear rate are the same, the shear stress fall down with the temperature increasing. The logarithm value of the shear stress decrease is nearly linear to that of the increase of temperature.b. At the same temperature and the content of NPMI, apparent viscosity decrease with the shear rate increase, and the logarithms of both of them exhibit linear relationship approximately, the slope n-1 varies at a certain range when the temperature fluctuate. At the same NPMI content and shear rate, apparent viscosity decrease with the temperature. The logarithm value of the apparent viscosity decrease is nearly linear to that of the increase of temperature.c. At the same NPMI content and shear rate, apparent viscosity decrease with the temperature increase and 1000/T is linear to the logarithm value of the apparent更多还原