【作者】 彭翠华；

【导师】 谭晓明；

【作者基本信息】 华中师范大学 ， 有机化学， 2008， 硕士

【摘要】 本文采用顺序聚合方法,首先利用蓖麻油（CO）与2,4一甲苯二异氰酸酯（TDI）反应生成预聚体（CO-PU）,然后将CO-PU与丙烯酸-2-羟-3-氯丙酯（HCAA）混合,用过氧化苯甲酰（BPO）作引发剂、二丁基二月桂酸锡（DBTDL）作催化剂制备出了一种新型的聚氨酯互穿网络聚合物（IPN-Interpenetrating Polymer Network）。利用游离TDI和—NCO的测定,研究了反应条件对CO-PU合成的影响;利用拉伸强度的测定,研究了体系组成对IPN力学性能的影响;利用热分析（DSC、TG）研究了IPN的结构及其耐热性能。结果表明:升高反应温度,CO-PU中游离TDI和剩余—NCO的含量都逐渐降低;提高nNCO/nOH比例,CO-PU中剩余—NCO的含量逐渐增大,游离TDI含量也逐渐增大;随着反应时间的延长,—NCO含量逐渐减小;加入催化剂DBTDL后,—NCO的含量明显降低。在常温条件下,CO-PU能够与HCAA形成IPN;随着固化时间的延长,IPN的拉伸强度逐渐增大,8d后基本达到最大值22.06MPa;增加nCO-PU/nHCAA或CO-PU中nNCO/nOH,IPN的拉伸强度都是先增大,后减小;在BPO和DBTDL的用量分别为0.5%和0.2%时,CO-PU/HCAA的拉伸强度最大;在形成CO-PU/HCAA后2265cm^-1处的—NCO特征吸收峰基本消失。在受热过程中IPN的分解是分步进行的,热分解分为三个阶段,在220℃～328℃首先分解的是聚氨酯网络,失重率为33.09%,然后在328℃～440℃时聚烯烃网络分解,失重率为53.32%,最后在440℃～500℃是整个体系开始分解形成小分子的过程,失重率为8.69%;体系组成对IPN的耐热性能有一定的影响,在nCO-PU/nHCAA为4:1、6:1和7:1的IPN中,nCO-PU/nHCAA为6:1的IPN耐热性最好,nNCO/nOH为2.0、2.5和3.0的IPN中,nNCO/nOH为2.5的IPN耐热性最好。聚氨酯网络的分解主要形成CO₂、H₂O和异氰酸酯、醇等,聚烯烃网络的分解主要形成烯烃、烷烃化合物;CO-PU/HCAA热分解反应是一级动力学,其热分解活化能根据体系组成不同而不同,nCO-PU/nHCAA为4:1、6:1和7:1的CO-PU-2.5/HCAA热分解活化能分别为:52.88kJ/mol、59.42kJ/mol和53.53kJ/mol;nNCO/nOH=2.0、2.5、3.0的IPN热分解活化能相差不大。更多还原

【Abstract】 A kind of prepolymer（CO-PU）were synthesized by 2,4-toluene diisocyanate（TDI） reacted with castor oil（CO）with steping polymerizing method in this paper.Then the new castor oil polyurethane interpenetrating polymer（IPN）were made by CO-PU mixed with 2-hydroxyl-3-chlorop ropyl acrylate（HCAA）,benzoperoxide（BPO）as initiator and dibutyl tin laurate（DBTDL）as catalyst at room temperature.The effect of reaction conditions on synthesis of CO-PU were studied by testing the free TDI and-NCO;the effect of the system composition on the mechanical properties of IPN were studied by testing tensile strength;the structure and heat resistant of IPN were studied by using thermal analysis（DSC,TG）.The results showed:the remaining -NCO and TDI content of CO-PU increased gradually with increasing temperature,the remaining -NCO and TDI content of CO-PU decreased with increasing the reatio of NCO/OH;the remaining -NCO content of CO-PU decreased with time;the remaining -NCO content of CO-PU decreased obviously after adding catalyst DBTDL.The castor oil polyurethane prepolymer CO-PU was mixed with HCAA,and formed IPN at room temperature;the tensile strength of IPN was gradually increased with curing time increaseing,with the maximum about 22.06MPa at 8th day.The tensile strength of CO-PU IPN increased at first and then decreased with increasing the double bond mole ratio of CO-PU and HCAA,with the maximum at 6:1,and NCO/OH mole ratio nNCO/nOH in CO-PU with the maximum at 2.5;the CO-PI/HCAA had the maximum tensile strength at the content of initiator BPO equal to 0.5%and catalyst DBTDL equal to 0.2%.The special absorption peak of-NCO at 2265cm^-1was disappeared after CO-PU/HCAA formed.The results of TG and DSC revealed that IPN’s thermal decomposition divided into three stages,the first was degeneration of the polyurethane network which lose weight was 33.09%from 220℃to 328℃,the second was degeneration of the polyurethane network that lose weight was 53.32%from 328℃to 440℃,the last was the melting of the segment that lose weight was 8.69%from 440℃to 500℃;The heat resistance was different about the system composition.The CO-PU/HCAA has the max△H and the best heat resistance when nCO-PU/nHCAA was 6:1.The CO-PU-2.5/HCAA has best heat resistance.The degeneration of the polyurethane network formed CO₂,H₂O and isocyanate,alcohol,et al.The degeneration of the polyolefine network formed major olefin and hydrocarbon of methane series.The degeneration of CO-PU/HCAA was one-order reaction,the activation energe respectively was different with different system compositon.The Ea was 52.88kJ/mol、59.42 kJ/mol and 53.53kJ/mol when nCO-PU/nHCAA was 4:1、6:1 and 7:1;The Ea was similar when nNCO/nOH was 2.0、2.5 and 3.0.更多还原