多羟基聚丁二烯的合成及其弹性体的制备研究

发布时间：2018-04-17 04:40

本文选题：端羟基聚丁二烯 + 多羟基聚丁二烯　；参考：《中北大学》2017年硕士论文

【摘要】：聚烯烃多元醇是一种制备弹性体的重要原料。常用的聚烯烃多元醇主要是分子链段中含有两个羟基的端羟基聚丁二烯(HTPB),其本身具有透明度好、粘度低、耐油耐老化、低温性能和加工性能好的优点。但用HTPB制备的聚氨酯弹性体一般具有较低的拉伸强度和断裂伸长率。多羟基聚丁二烯(PHPB)是结构中比HTPB含有更多羟基的遥爪型液体材料。由PHPB与异氰酸根反应生成的支化聚氨酯弹性体比线性聚氨酯弹性体结构中的氨酯基氢键多。高聚物分子间氢键的增多使得分子之间内聚力增大,提高了聚氨酯弹性体力学性能。因此,通过分子设计改性HTPB制备出分子链段中含有多个羟基的PHPB具有一定的实用价值和科学理论意义。1.本文通过分子设计在氢氧化钠碱性条件下,以HTPB和环氧氯丙烷(ECH)为原料,四丁基溴化铵(TBAB)为催化剂,首次在HTPB两端接入更多的羟基制得PHPB。并用红外光谱仪(IR)、氢核磁共振仪(1H-MNR)进行测试表征。通过单因素实验优选了合成PHPB的工艺条件。合成PHPB的较适宜的条件为:反应温度为55℃,反应时间1.5 h,原料、氢氧化钠以及催化剂的摩尔比为n(HTPB):n(ECH):n(Na OH):n(TBAB)=1:2.9:3:0.03。TG分析结果可知,较佳条件下合成的PHPB的热稳定性比HTPB的热稳定性好。2.以合成的PHPB为原料,甲苯二异氰酸酯(TDI)为固化剂,1,4-丁二醇(BDO)为扩链剂,二月桂酸二丁基锡(DBTDL)为催化剂,采用一步法制备聚氨酯弹性体。利用差示扫描量热仪(DSC)、热重分析仪(TG)以及电子万能拉伸试验分析仪对聚氨酯弹性体的力学性能和热性能进行测试分析。实验结果表明,当固化参数R=1.2,催化剂用量为0.6%,n(BDO):n(PHPB)=3:1,固化温度为65℃时,制备的聚氨酯弹性体力学性能较好。较优条件下制得的弹性体进行的拉伸强度为4.04 MPa,断裂伸长率为282.02%,玻璃化转变温度在-20℃左右,热分解温度为226℃,最大热失重速率出现在278.71℃和464.18℃,表现出优异的热学性能。3.不同的HTPB和PHPB固化体系粘度随时间的变化不同,采用DV2T型旋转粘度仪测定了不同的HTPB和PHPB固化体系粘度随时间的变化。测定结果显示:BDO作为扩链剂,DBTDL作为催化剂,固化参数R=1.2,HTPB-TDI和PHPB-TDI固化体系较佳。固化参数R相同时,PHPB-TDI-BDO-DBTDL体系固化所需时间比HTPB-TDI-BDO-DBTDL体系所用时间短。4.采用非等温差示扫描量热法研究了二月桂酸二丁基锡对HTPB-TDI-BDO和PHPB-TDI-BDO体系固化反应的动力学影响。结果表明,HTPB-TDI-BDO固化体系不加催化剂时表观活化能为60.28 KJ·mol-1,加入二月桂酸二丁基锡的表观活化能为48.39 KJ·mol-1,反应级数分别为0.886和0.864。PHPB-TDI-BDO固化体系无催化剂时表观活化能为52.38 KJ·mol-1,而加入催化剂二月桂酸二丁基锡的表观活化能为39.16 KJ·mol-1,反应级数分别为0.873和0.843。该结果说明,二月桂酸二丁基锡的加入降低了HTPB-TDI-BDO和PHPB-TDI-BDO固化体系的表观活化能,加快了固化反应速率,缩短了固化时间;PHPB-TDI-BDO固化体系比HTPB-TDI-BDO固化体系的表观活化能低,所需固化时间更短。
[Abstract]:Polyolefin polyol is an important raw material for preparation of polyolefin elastomer. Polyol is mainly used for hydroxyl terminated polybutadiene chains containing two hydroxyl groups (HTPB), which itself has good transparency, low viscosity, anti-aging oil, has the advantages of low temperature performance and good machining performance. But the polyurethane elastomer with HTPB prepared with low tensile strength and elongation at break. Polyhydroxylated polybutadiene (PHPB) is a telechelic liquid material containing more than HTPB in the structure of hydroxyl groups. Hyperbranched polyurethane elastomer produced by the PHPB and isocyanate reaction than ammonia ester bond of linear polyurethane elastomer structure in the multi. Cohesion between increased polymer molecular hydrogen bonds between the molecules increases and improves the mechanical properties of polyurethane elastomer. Therefore, through the molecular design of modified HTPB prepared by molecular chains containing multiple hydroxyl groups with a PHPB The practical value and scientific theory significance of.1. through molecular design in sodium hydroxide alkaline conditions with HTPB and epichlorohydrin (ECH) as raw materials, four Butyl Ammonium Bromide (TBAB) as the catalyst for the first time in the hydroxyl HTPB ends more access to the system PHPB. and infrared spectrometer (IR), hydrogen nuclear magnetic NMR (1H-MNR) were characterized by single factor experiment. The optimum process conditions of the synthesis of PHPB. The optimum conditions for the synthesis of PHPB, reaction temperature 55 C, reaction time 1.5 h, raw materials, sodium hydroxide and catalyst molar ratio of n (HTPB): n (ECH): n (Na OH) n: (TBAB) the results of =1:2.9:3:0.03.TG analysis, compared with the thermal stability of PHPB synthesized under optimal conditions than the good thermal stability of.2. HTPB using the PHPB as raw material, toluene diisocyanate (TDI) as curing agent, 1,4- butanediol (BDO) as chain extender, butyl tin two lauric acid two (DBTDL) for catalytic Agent, preparation of polyurethane elastomer by one step method. By using differential scanning calorimetry (DSC), thermogravimetric analyzer (TG) test and analysis of mechanical properties and thermal properties of electronic universal tensile test analyzer of polyurethane elastomer. The experimental results show that when the curing parameters of R=1.2, the amount of catalyst is 0.6%, n (BDO): n (PHPB) =3:1, the curing temperature is 65 degrees centigrade, the preparation of polyurethane elastomer properties. The tensile strength under the optimum condition of the elastic body is 4.04 MPa, the elongation is 282.02% glass transition temperature of -20 degrees Celsius, the thermal decomposition temperature of 226 DEG C, the maximum heat loss rate in 278.71 degrees and 464.18 degrees, showing excellent thermal properties of.3. HTPB PHPB and different curing system viscosity with different time, different HTPB and PHPB curing system viscosity with time was measured by DV2T type rotary viscometer The determination results showed that: BDO as chain extender, DBTDL as catalyst, curing parameters R=1.2, HTPB-TDI and PHPB-TDI curing system is better. The curing parameters of R phase at the same time, the PHPB-TDI-BDO-DBTDL system required for curing time than HTPB-TDI-BDO-DBTDL system in short time.4. using non isothermal effects of tributyltin two lauric acid two kinetics of HTPB-TDI-BDO and the PHPB-TDI-BDO curing reaction DSC. The results showed that the HTPB-TDI-BDO curing system without catalysts. The apparent activation energy is 60.28 KJ / mol-1, adding acid two butyl tin two laurel activation energy was 48.39 KJ - mol-1, the reaction order was 0.886 and 0.864.PHPB-TDI-BDO respectively. No apparent catalyst curing system the activation energy was 52.38 KJ and two mol-1, adding acid butyl tin catalyst two bay the apparent activation energy is 39.16 KJ - mol-1, the reaction order is 0.873 and 0.843. respectively the results That two lauric acid two butyl tin decreased with the addition of HTPB-TDI-BDO and PHPB-TDI-BDO curing system of apparent activation energy, accelerate the curing reaction rate, shorten the curing time; PHPB-TDI-BDO curing system of HTPB-TDI-BDO curing system than the apparent activation energy is low, the curing time is shorter.

【学位授予单位】：中北大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ334

【参考文献】