中国胶粘剂

虫胶片作为一种天然胶粘剂，因其施工便捷、力学性能较好而受到广泛关注。然而，虫胶原胶的性能易受气候、品种的影响，且目前缺乏针对塑料和金属基底的粘接工艺研究，导致其粘接强度波动性较大，进而影响粘接连接的可靠性。本文通过改变虫胶片类型、虫胶-乙醇溶液(虫胶漆)配制有效期、晾置时间以及粘接基底的种类等变量，发现虫胶片的粘接强度与其理化性质密切相关。酸值达标且溶液黏度较高的虫胶片表现出更优的粘接性能，同时具有较高的熔点(T_m)和熔化热焓(ΔH_m)、较低熔程(ΔT_m)的虫胶片通常具有更高的粘接强度。粘接工艺方面，基底表面均匀涂覆单层虫胶漆，并于涂胶后立即完成叠合，可获得最佳粘接性能。此外，粘接材质对虫胶片的固化过程和粘接性能存在显著影响，其中聚甲基丙烯酸甲酯(PMMA)的粘接强度最高(约2.8 MPa)，铝片次之(约1.0 MPa)，聚醚醚酮(PEEK)最低(约0.5 MPa)。基底经过打磨处理虽能提升粘接强度，但需延长固化时间以达到最佳性能。本文为优化虫胶片粘接工艺和提高其在不同基底上的粘接性能提供了理论依据和实践指导。

Shellac flakes,as natural adhesive,have received significant attention due to their ease of application and favorable mechanical properties. However,the performance of raw shellac is easily affected by climate and variety,and there is currently a lack of research on bonding processes for plastic and metal substrates,resulting in significant fluctuations in bonding strength and affecting the reliability of bonding connections.It was found in this article that the bonding strength of shellac flakes was closely related to their physical and chemical properties by changing variables such as the type of shellac flakes,the effective period of shellac-ethanol solution(shellac paint) preparation,the drying time,and the type of bonding substrate.Shellac flakes that met the acid value standard and had higher solution viscosity exhibited better bonding performance,while shellac flakes with higher melting points(T_m) and melting enthalpy(ΔH_m),as well as lower melting ranges(ΔT_m) typically had higher bonding strength.In terms of bonding process,the substrate surface was uniformly coated with a single layer of shellac paint,and the lamination was completed immediately after bonding to achieve the best bonding performance.In addition,the bonding material had a significant impact on the curing process and bonding performance of shellac flakes,with polymethyl methacrylate(PMMA) having the highest bonding strength(about 2.8 MPa),followed by aluminum sheet(about 1.0 MPa),and polyether ether ketone(PEEK) having the lowest(about 0.5 MPa).Although polishing the substrate could improve the bonding strength,it was necessary to extend the curing time to achieve optimal performance.This article provided theoretical basis and practical guidance for optimizing the bonding process of shellac flakes and improving their bonding performance on different substrates.