改性聚氨酯浇注胶的研究

【作者】 孟季茹；

【导师】 秦华宇；

【作者基本信息】 西北工业大学 ， 应用化学， 2001， 硕士

【摘要】 浇注型聚氨酯弹性体的制备多采用预聚法工艺，但采用该工艺进行浇注时存在预聚物对温度敏感；对设备的要求较高；预聚物的储存稳定性较差，不易长期存放；使用时受预聚物种类的限制，不能任意改变弹性体的性能；工艺过程较长等不足和弊端，因而迫切需要对预聚法工艺进行改性或采用新型的制备方法以替代预聚法工艺。 鉴于此，本课题采用一步法工艺制备了取代乙烯改性浇注型聚氨酯体系，同时为进行比较和适应不同场合的需要，制备了取代乙烯单体/聚氨酯的预聚法工艺体系及取代乙烯预聚体/聚氨酯体系。研究了三种体系的反应性、储存性以及浇注体系的主要力学性能及其影响因素。结果表明，控制-NCO/-OH比值（R）、低分子二元醇与聚酯多元醇的-OH摩尔比（α）、催化引发体系用量、取代乙烯含量、交联剂含量、填料在甲组分中的含量以及阻聚剂含量等，可得到具有优良的反应性、工艺性、储存性及综合力学性能的稳定体系，能满足不同使用要求场合的需要。通过实验我们认为三种体系的性能均较佳，分别适应于不同的应用场合。但综合考虑体系的性能，我们认为采用一步法制备取代乙烯改性浇注型聚氨酯体系时，具有节省能源、施工方便等优点，可在室温下固化成型，对设备要求较低，成本较低；制得的浇注胶室温下的粘度较低，固化后的体系与ABS和EPDM的粘接性良好，属互穿共轭型粘接机理，具有较大的发展前景。 通过中等规模实际生产测定，由该法得到的改性浇注胶具有较佳的综合性能：室温下的凝胶时间为80min左右，48h完全固化；拉伸强度26.OMPa，拉伸剪切强度（ABS-EPDM）15.OMPa，断裂伸长率300％，永久变形率10.0％，热空气老化强度变化率-1.0％，耐酸后强度变化率-0.05％，硬度（邵D）88。该体系与目前国内广泛应用的进口浇注胶相比，其综合性能较佳，可替代进口胶，改变国内汽车等行业铅酸蓄电池用浇注胶靠进口的局面。更多还原

【Abstract】 This project studied three systems, which can be used in different fields--methyl methacrylate-styrene/polyurethane by one-step process, methyl methacrylate- styrene/polyurethane by two-step process, the prepolymer of methyl methacrylate-styrene/ polyurethane. The influence of the reactivity, storage life, and the mechanical properties of the three systems is studied. The results show that -NCO/-OH (R) , the molar rate of hydroxyl of binary alcohol and polyols (a ) ,the initiator, accelerator, dibutyltin dilaurate (P) as the catalyzer, the content of vinyl monomer (y) , the content of divinylbenzene as the linker of styrene (e ) , and fillers content have effects on reaction rate and mechanical properties in more or less degree. From the study, we can draw a conclusion that the three systems have good properties, and can be used in many occasions; the first system have best peffomiance compared with other two systems, and when R1.10, a 0.50,BPO/ (MMA+St) =1.6%, DMA! (MMA+St) =0.9%, e =4%, P =0.04%, y =30%,with 30-35% ~~o2 in the component of polyols, the modified system exhibits suitable reactivity with 80mm gel-time and can be completely cured alter 48 hours at the room temperature. Simultaneously the glue line possesses favorable properties: the tensile strength is 26.OMPa, breaking elongation 300%, permanent deformation 10.0%, the loss of strength alter thermal air aging and acid corrosion are -1.0% and 0.06% respectively, the Shore hardness 88 (D) and extensional shearing strength is 15.OMPa (ABS-ethylene propylene terpolymer) ,can be used in most occasions especially as an embedded material or as a casting material in wiring.更多还原