【作者】 柴玉叶；

【导师】 张淑芬； 兰云军；

【作者基本信息】 大连理工大学 ， 应用化学， 2011， 博士

【摘要】 针对线形聚合物皮革复鞣填充材料结构单一、与皮革胶原纤维缺乏立体交联,性能日益不能满足现代制革生产要求,以及经典超支化聚合物结构过于致密,分子柔顺性和机械性能欠佳而不适合直接用于皮革复鞣填充的现状,本文采用烯类支化单体,与甲基丙烯酸通过自由基聚合,制备支化聚合物皮革复鞣填充材料。采用三羟甲基丙烷(TMP)和马来酸酐(MA),合成单三羟甲基丙烷马来酸酯(MTPM)系列支化单体。优化合成条件为：对于MTPM-20和MTPM-25,90℃反应240min, MA单酯化率接近100%；对于MTPM-30,0.2%对甲苯磺酸催化剂,90℃下反应240min, MA单酯化率97.82%。经酯化率法和核磁共振法计算, MTPM-20、MTPM-25、MTPM-30和MTPM-30-C的双键官能度分别为2.0、2.5、2.7(2.8)和3.0(2.9)；其中M3质量百分数分别为20.8%、51.2%、67.5%和91.9%。以系列MTPM分别与甲基丙烯酸(MAA)进行自由基共聚,制备系列长链支化聚合物(LBP)。优化合成条件为：n(MAA)/n(MTPM)为=18：1,APS用量6.0%,反应温度为83-85℃,反应时间3h,单体中和度0.6,投料方式为MAA和APS同时后滴加。lg[η]-lgMw关系偏离Mark-Houwink线性关系呈曲线的结果表明,LBP系列聚合物具有长链支化结构。激光光散射检测器测定LBP聚合物的分子质量及分布,发现分子质量大小在15000-27000g/mol之间,分布处在1.3-1.6之间。分别通过支化概率和支化因子对LBP系列聚合物的支化程度进行表征,两种方法得到相同结论：LBP聚合物支化程度随MTPM单体平均双键官能度增加而增加。对LBP-25聚合物水溶液流变行为研究表明,其水溶液粘度随着体系pH值增加先降后升,在pH 6.0时出现最小值,其流变行为接近于牛顿流体特征。耐酸性能研究表明,LBP-20在盐酸溶液中的沉淀点接近3.0,LBP-25、LBP-30和LBP-30C的沉淀点均低于1.0。DSC分析表明LBP聚合物的Tg在279℃到290℃之间,与甲基丙烯酸(279.71℃)接近,说明二者具有相似的分子柔顺性。TGA/DTG分析结果表明LBP聚合物热稳定性符合皮革生产和加工过程的要求。应用表明,LBP系列聚合物具有优异的复鞣和填充性能,对皮革胶原纤维有很好的分散作用,可赋予皮革丰满、柔软的手感；对皮革染色性能负面影响小。其中LBP-25综合应用性能最佳,优于Baytigan AR和ART-Ⅱ。更多还原

【Abstract】 Current linear polymer retanning-filling agents are increasingly unable to fulfil requirements of manufacturing high-quality leathers. Classical hyperbranched polymers, which have been used as alternatives, are not suitable to treat skins due to poor flexibility or mechanical properties resulted from its impact structure. Focusing on above dilemma, we employed unsaturated multi-functional monomers to polymerize with usual vinyl monomers to prepare long-chain branched polymers as retanning&filling agents for leather-making via traditional free radical polymerization.Tri-hydroxymethylpropane(TMP) is employed to react with maleic anhydride(MA) to produce mono-trihydroxymethylpropane maleates(MTPMs). Optimized reaction conditions are obtained by determinating mono-esterification rate of MA: reaction temperature 90℃and time 240 min for MTPM-20, MTPM-25 and MTPM-30; MTPM-30-C is prepared by addition of 0.2%(wt%) catalyst without producing diester of maleates. The average double bond functionality(ADF) of MTPM-20,MTPM-25,MTPM-30 and MTPM-30-C are calculated by esterification rate and NMR, results are respectively 2.0,2.5,2.7(2.8) and 3.0. Mole percentages of mono-trihydroxymethylpropane tri-maleates(M3) in aforementioned MTPMs determined by 13CNMR are 20.8%、37.6%、67.5%and 91.9%, respectively。Series of long-chain branched polymers(LBPs) are synthesized by aqueous copolymerization of MTPMs with MAA via free radical polymerization. The optimized conditions:n(MAA)/n(MTPM)= 18:1, APS 6.0%(wt%),temperature 83-85℃, time 3h, feeding methodⅢ(MAA and APS simultaneously added after MTPMs addition) and degree of neutralization for monomers 0.6. NMR and low angle laser light scattering(LALLS) are employed to characterize the architecture of LBPs. The results of LALLS show that intrinsic viscosity([η]) and molecular weight(Mw) relationships for LBPs do not follow a power law relationship, from which the branched architectures of LBPs are identified. The results of LALLS indicate that Mw of LBPs is located in the range from 15000g/mol to 27000g/mol, Mw/Mn 1.3-1.6.The branched architectures of LBPs are characterized by probability of branching (Pb) and branching factor g’, the results of both determinations reveal that degree of branching increases with the increasing of ADF of MTPMs.The effects of pH and shear rates on the aqueous viscosity of LBP25 are investigated, the results show that its rheological behavior comes close to Newtonian fluid and its aqueous viscosities display a minimum at pH-6.0. The results of DSC show that LBP molecules have nearly same flexibility as that of poly-methacrylic acid due to their close Tgs(LBPs:279～290℃, poly-MAA:279.71℃). The results of TGA/DTG manifest that each of LBPs has a two-stage decomposition from 50℃to 650℃and has thermal stability suitable for leather-making.LBPs are used to treat chrome-tanned sheepskins, the treated leathers are evaluated and the results indicate that LBPs, which perform well in filling and retanning leathers, produce result leathers excellent softness, plumpness and flexibility without effecting the dyeing of leathers. The LBP-25 polymer has better application properties than both other LBPs and Baytigan AR and ART-Ⅱ.更多还原