HTPB/IPDI推进剂与衬层界面黏结性能研究进展

简述了推进剂与衬层界面黏结机理及造成界面附近推进剂软化的原因,总结了国内外关于影响端羟基聚丁二烯(HTPB)/异佛尔酮二异氰酸酯(IPDI)推进剂与衬层界面黏结性能因素以及改善界面黏结性能的技术途径的研究成果,提出了改善该类推进剂与衬层界面黏结性能的建议.     

聚氨酯缔合型增稠剂的研制

利用异佛尔酮二异氰酸酯（IPDI）与一定相对分子质量的聚乙二醇进行本体聚合得到聚氨酯单体，加入扩链剂和封端剂进行改性，最后与溶剂和助溶剂进行复配成缔合型聚氨酯增稠剂成品。对合成过程中的温度、催化剂、加料次序及滴加速率等条件进行了研究，同时对合成的缔合型聚氨酯增稠剂与国外某知名公司类似产品做了在乳胶漆中的应用对比研究。     

常温固化型四氟树脂涂料的研究

主要介绍了国内外不同FEVE型四氟树脂在性能方面的差异及各种脂肪族异氰酸酯交联剂对四氟树脂涂料性能的影响,并探讨了各种影响因素的作用机理。     

环氧树脂改性脂肪族水性聚氨酯的合成及其性能

以异佛尔酮二异氰酸酯(IPDI)、聚醚多元醇2020、聚醚多元醇3050、酒石酸和环氧树脂E-44为主要原料,合成了内交联改性的聚醚型脂肪族水性聚氨酯(WPU)乳液,讨论了影响乳液稳定性及胶膜力学性能的因素。结果表明,当环氧树脂质量分数在4.0%～6.0%、nNCO∶nOH摩尔比在4.2～4.4、酒石酸质量分数在2.0%～2.2%、聚醚多元醇质量比m2020/m3050在为2.0～2.2之间时,可得耐水性、稳定性、力学性能优良的改性WPU乳液。     

非等温DSC研究超支化聚醚/PEG/IPDI体系的固化反应动力学

采用非等温差示扫描量热法(DSC)研究了超支化聚醚对聚乙二醇/异佛尔酮二异氰酸酯体系(PEG/IPDI)固化反应动力学的影响。结果表明,PEG/IPDI体系的固化反应表观活化能约为53.278 kJ/mol,反应级数为0.914,指前因子为1.500×105min-1;加入6%的超支化聚醚后,体系的固化峰温升高,表观活化能、反应级数和指前因子分别提高至87.577 kJ/mol、0.960、1.201×1010min-1,机理函数仍遵循Avrami-Erofeev方程G(α)=[-ln(1-α)]n,只是方程中的指数n有所变化。超支化聚醚对PEG/IPDI体系的固化反应有一定的延缓作用,但不改变固化机理。浅析了超支化聚醚影响PEG/IPDI体系固化的原因。     

硬段含量对水性聚氨酯性能的影响

以聚酯多元醇和异佛尔酮二异氰酸酯(IPDI)为主要原料，引入亲水单体二羟甲基丙酸(DMPA)，按不同配比合成了系列聚氨酯乳液。考察了硬段含量对乳液粒径、表观黏度、膜吸水性、硬度、力学性能的影响，并通过动态力学性能测试(DMA)研究了软段和硬段的玻璃化转变温度。结果表明：提高-NCP/-0H物质的量之比、DMPA用量均使聚氨酯中软段的玻璃化温度Tg(s)降低，硬段的玻璃化温度Tg(h)升高，△T值增加，软硬段相分离程度增加。随乙二胺用量的增加，会使软段玻璃化转变温度Tg(s)移向高温，软硬段相分离程度降低；硬段含量提高，胶膜硬度增加，拉伸强度增加，胶膜耐水性降低。     

聚氨酯丙烯酸酯的合成研究及应用

以IPDI,PEG1000和HEMA为原料合成了可紫外光固化的聚氨酯丙烯酸酯低聚物(PUA),用作凝胶聚合物电解质中的聚合物基体。对合成的产物(PUA)进行红外图谱分析,并讨论了合成过程中反应温度,反应时间,反应物配比等因素的影响。结果表明较佳的合成条件为:n(IPDI):n(PEG1000):n(HEMA)=1:2:2.08,第一步的反应温度在60～75℃,反应时间为2 h;第二步的在55～65℃,时间为2.5 h。     

Surgical adhesives: Systematic review of the main types and development forecast

Due to several advantages over traditional approaches (e.g. sutures and staples), surgical adhesives are excellent materials for wound closure. For several decades intensive research activities have been carried out to enhance the efficiency of the adhesives in different tissues and application conditions. This article provides a concise literature review of different types of adhesives in order to understand their structure-properties relationship. Some of the most important commercial adhesives available are presented and discussed in terms of limitations and applications. The recent advances reported in the literature that could provide new avenues to the development of more efficient adhesives inspired in nature strategies are also discussed.     

Kinetic study of the reaction between hydroxyl-terminated polybutadiene and isophorone diisocyanate in bulk by quantitative FTIR spectroscopy

A kinetic study of the reaction between a hydroxyl-terminated polybutadiene (HTPB) and isophorone diisocyanate (IPDI) was carried out in the bulk state by using quantitative Fourier transform infrared (FTIR) spectroscopy. The reaction is shown to obey a second-order rate law, being first order in both the HTPB and IPDI concentrations. The activation parameters obtained from the evaluation of kinetic data are ΔH‡ = 41.1 ± 0.4 kJ mol, ΔS‡ = −198 ± 2 J K⁻¹ mol⁻¹ and E_a = 43.8 ± 0.4 kJ mol⁻¹, which are quite different from the solution values. However, they are in agreement with the results obtained on propellants by torsional braid measurements. The large negative value of the activation entropy is indicative of an associative mechanism, which is in accord with the second-order rate law for the polyurethane formation. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 1979–1983, 1997     

异佛尔酮二异氰酸酯溶液扩链合成聚乳酸类药物缓释剂

以外消旋乳酸(D,L-LA)直接熔融聚合得到的低相对分子质量聚外消旋乳酸(PDLLA)为原料,通过二异氰酸酯扩链合成了聚乳酸类药物缓释材料。当采用异佛尔酮二异氰酸酯(IPD I)为扩链剂,反应在四氢呋喃溶液中进行时,扩链反应工艺条件为:扩链剂用量n(NCO)∶n(OH)=2∶1时,66℃下回流反应2 h,相对分子质量增加近2.92倍。与2,4-甲苯二异氰酸酯(TD I)扩链法相比,IPD I溶液扩链法不仅提高产物相对分子质量的效果非常接近,具有反应温和、条件易调控等优点,而且使所得聚乳酸类药物缓释材料具有较高的生理安全性。