热熔压敏胶粘接性能的流变学研究

研究了苯乙烯嵌段共聚物系热熔压敏胶的动态流变学行为和持粘力之间的联系,主要研究了决定持粘力的流变学参数.研究证明,持粘力受到体系的蠕变过程的控制,可以通过较高温度下得到的持粘力数据来预测室温持粘力的大小.研究了液体树脂含量对持粘力的影响,提出损耗角正切(tan δ)最小值及其对应的温度是决定热熔压敏胶持粘力的关键流变学参数.     

环氧化SDS型热熔压敏胶的制备及粘接性能研究

采用苯乙烯-丁二烯-苯乙烯(SBS)和苯乙烯-异戊二烯-苯乙烯(SIS)嵌段共聚物,并配合极性的环氧化SBS(ESBS)和环氧化SIS(ESIS)作为基体材料,制备了环氧化SDS(苯乙烯系热塑性弹性体)型热熔压敏胶。研究了ESBS和ESIS用量对压敏胶的初粘力、持粘力和在不同极性底材上剥离强度的影响。结果表明,随着ESBS和ESIS用量的增加,压敏胶的初粘力和持粘力下降,在聚乙烯(PE)上的剥离强度下降,但在聚氯乙烯(PVC)和不锈钢上的剥离强度先增加后下降。当ESBS和ESIS的质量份数均为20份时,压敏胶的初粘力和持粘力分别为23#和43.6 h,在PVC和不锈钢底材上的剥离强度分别达到0.82 N/mm和1.10 N/mm。     

分子量对压敏胶粘接性能的影响

本文综述了分子量及其分布与压敏胶粘接性能的关系，通常粘接性能随分子量的增大而提高。当压敏胶保持足够高的分子量和较宽的分子量分布时，才能获得综合性能较好的压敏胶     

探究合成树脂和天然树脂对热熔压敏胶性能的影响

采用单因素法探究天然树脂和合成树脂对热熔压敏胶性能的影响。研究结果表明:热熔压敏胶高分子溶液可以用Arrhenius黏流活化能方程来拟合。增黏树脂可赋予热熔压敏胶黏附性能,合成树脂有利于热熔压敏胶环形初粘力和持粘力的提高,天然树脂有利于热熔压敏胶180°剥离力和软化点的提高。适量提高天然树脂质量百分比有利于提升热熔压敏胶的环形初粘力、180°剥离力和持粘力。     

共混热塑性弹性体热熔压敏胶的制备及性能研究

以苯乙烯热塑性弹性体(HYBRAR7311)和丙烯酸酯热塑性弹性体(LA2250)为主体树脂,2种材料优势互补,制备的热熔压敏胶(HMPSA)性能优良,且工艺设备简单。采用正交实验较优热熔压敏胶配比,在此基础上探讨了填料硅微粉对热熔压敏胶性能的影响,并比较了较优配方热熔压敏胶与自制SIS热熔压敏胶和乳液压敏胶的力学性能。针对3种压敏胶力学性能上的差异,对3种压敏胶的粘弹性能进行了对比研究,结果表明,压敏胶在低频区(0.01~0.1 Hz)贮能模量越小,初粘性越大,E’’(f 1)/E’(f 2)越大(f 1=32.03 Hz,f 2=0.07 Hz),剥离强度越大。     

卫生用品用环保型热熔压敏胶的研制

介绍了以嵌段共聚物苯乙烯-丁二烯-苯乙烯(SBS)为基础材料制备卫生用品用热熔压敏胶的方法,讨论了其它原材料:增粘剂、增塑剂、防老剂以及反应温度、反应时间、空气中的氧对热熔压敏胶性能的影响。     

SIS型热熔压敏胶影响因素分析

通过熔融混合制备SIS型热熔压敏胶,重点考察了增黏树脂、软化油、SIS结构参数等因素对热熔压敏胶黏度、初黏、剥离强度的影响。采用单因素实验法系统探讨软化油、增黏树脂、主体树脂等对热熔压敏胶黏度、初黏、剥离等性能的影响,并进一步探讨增黏树脂内在物理化学结构对热熔压敏胶的影响,结果表明:增黏树脂软化点高低对热熔压敏胶的黏度和剥离强度有重大影响。通过正交试验法得出:影响黏度的关键因素是油含量,影响剥离强度的关键因素是增黏树脂,影响初黏的关键因素是油含量和增黏树脂。     

增黏树脂差异性对热熔压敏胶外观及性能的影响

热熔压敏胶是一类集热熔和压敏双重特性的胶黏剂。松香树脂、萜烯树脂及石油树脂作为增黏剂较为广泛地应用于热熔压敏胶中。研究发现,由于生产原料及生产工艺的细小差别,不同厂家生产的同类型增黏树脂在空间结构和相对分子质量上均有差异,所制备的热熔压敏胶性能也明显不同。这种差异性对控制热熔压敏胶的产品质量是非常不利的,对我国松香树脂及萜烯树脂产品的出口有很大影响。因此,研究生产原料的组成、生产工艺、分子结构对松香树脂、萜烯树脂的应用性能的影响是非常有意义的。     

热熔压敏胶的粘接性能和流变行为的关系

研究了热熔压敏胶初粘性、剥离强度与流变学行为之间的关系。研究发现,用温度扫描方法得到的流变曲线与压敏胶主曲线较为一致,因此可以将其转化为不同弛豫时间下的流变行为。通过调整液体树脂含量,设计出一系列橡胶平台模量保持相对不变的同时,具有不同玻璃化温度的压敏胶配方,其中玻璃化温度相同的压敏胶配方,具有基本相同的环形初粘力和剥离强度。     

APAO热熔压敏胶的流变性能研究

采用高级流变扩展系统（ARES）研究了基体树脂无规聚α 烯烃(APAO)的牌号、增黏剂C5石油树脂用量和增塑剂种类对APAO热熔压敏胶流变性能的影响。结果表明,APAO相对分子质量越大,热熔压敏胶的剪切黏度越高;随着C5石油树脂用量的增加,热熔压敏胶的剪切黏度会出现一个峰值;增塑剂的相对分子质量越小,热熔压敏胶剪切黏度越小,而增塑剂的种类对热熔压敏胶的切敏性无影响;同时热熔压敏胶的温敏性良好,温度升高,热熔压敏胶的黏度下降,高温低频率时切敏性较差,高温高频率时切敏性良好,随着温度的降低,切敏性变好。     

喷涂聚脲弹性体与潮湿混凝土基材粘接性能研究

针对水利水电混凝土工程常处于潮湿状态的特点．介绍了应用于潮湿混凝土基材的喷涂聚脲弹性体涂层的粘接性能,试验结果表明,SK型表面处理剂与潮湿混凝土基材粘接强度能达到5．0MPa．施用表面处理剂后再喷涂聚脲弹性体涂层粘接强度能达到2．5MPa。     

底涂剂对聚氨酯密封剂粘接性能的影响

以异氰酸酯(TDI)和聚醚多元醇(如N-220、N-330和EP-330N等)为主要原料,合成了高性能双组分PU(聚氨酯)密封剂。采用不同底涂剂对水泥基材进行表面涂敷,以增强PU密封剂/水泥基材胶接件的粘接性能。结果表明:当D1[环氧树脂(EP)类底涂剂]作为PU密封剂/水泥基材胶接用底涂剂时,其粘接效果低于D2(PU类底涂剂);用硅烷偶联剂改性D1,可有效增强EP/PU间的界面结合力,提高PU密封剂/水泥基材胶接件的耐水性和耐热性;在D3(由EP、KH-550硅烷偶联剂和二乙烯三胺组成)未干时浇铸PU密封剂,则PU密封剂/水泥基材胶接件的性能满足JC/T 976—2005标准要求。     

Copper bonding silicon nitride substrate using atmosphere plasma spray

Silicon nitride (Si₃N₄) is an excellent engineering ceramic with high strength, fracture toughness, wear resistance, and good chemical and thermal stability. Recently, the enhanced thermal conductivity enables Si₃N₄ to have potential application prospects in the electronic and orthopedic fields. Metal bonding with Si₃N₄ is often the key to these applications. Here we report a facile approach for the titanium-activated Cu bonding on Si₃N₄ substrates using an atmosphere plasma spray (APS) process. With X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) observation, it was shown that the interaction between the pre-bonded Ti (by APS) on Si₃N₄ promoted the adhesion and high bonding strength of APS Cu on Si₃N₄. The interfacial structure and phases were characterized, and tensile strength, electrical resistivity, thermal conductivity, and residual stress of Cu bonded Si₃N₄ were measured accordingly. The APS deposited Cu layer is dense, has a high purity, and is joined firmly with Ti pre-bonded Si₃N₄ substrate. The maximum tensile strength between Cu and Si₃N₄ is as high as 89.4 MPa. The Si₃N₄ substrate bonded with highly dense Cu demonstrates a low surface resistivity of 8.72 × 10⁻⁴ Ω∙mm, and high thermal conductivity of 98.12 W/m·K, which shows potential applications in electronic devices.     

丙烯酸金属盐对金属-橡胶黏接体力学性能的影响

研究了丙烯酸金属盐对金属-橡胶(天然橡胶／溶聚丁苯橡胶共混物)黏接体力学性能的影响。结果表明。将炭黑填充量减少20-30份,加入2-5份的丙烯酸锌原位增强被黏橡胶。不仅保持了金属一橡胶黏接体的力学性能。而且明显改善了被黏橡胶的耐撕裂性能、与金属的黏合效果以及剥离破坏状况。破坏形貌变化也得到了明显改善。     

-NCO基硅氧烷底涂剂对聚氨酯密封胶粘接性能的影响

采用有机溶剂稀释KSA(-NCO基硅氧烷化合物),并以此作为单组分湿固化聚氨酯(PU)密封胶的玻璃基材底涂剂。采用单因素试验法考察了无底涂剂试样、含传统Z-6040底涂剂试样和含KSA底涂剂试样对PU密封胶与玻璃基材之间粘接性能的影响。结果表明:当KSA底涂剂的固含量为15%、底涂剂与密封胶的涂敷间隔时间为15 min时,含KSA底涂剂的试样比含传统Z-6040底涂剂的试样更能有效提高PU密封胶与玻璃胶接件的综合性能;前者的剥离强度为9.5 N/mm且为内聚破坏,水中浸泡7 d后其剥离强度仅下降32%,4次高低温循环后其剥离强度仍高达4.1 N/mm。     

C_5树脂对SIS/RLPO基热熔压敏胶性能的影响

以SIS/RLPO(苯乙烯-异戊二烯-苯乙烯与丙烯酸乙酯-甲基丙烯酸甲酯-甲基丙烯酸氯化三甲胺基乙酯)共混物作为HMPSA(热熔压敏胶)的基体树脂,考察了C5树脂对基体树脂的相容性及其HMPSA黏附性能的影响。结果表明:随着C5树脂用量的不断增加,PS(聚苯乙烯)相的Tg(玻璃化转变温度)基本不变,PI(聚异戊二烯)相的Tg逐渐趋近于C5树脂的Tg,说明C5树脂与PI相具有较好的相容性,而与PS相的相容性相对较差;当SIS/C5/RLPO共混物中三者质量比为30∶50∶60时,相应HMPSA具有适宜的黏附性能,同时其双连续相结构有利于亲水性药物的释放。     

高性能双组分室温固化环氧胶的研制

以环氧E-51、增韧剂R-1000、偶联剂KH-560、聚酰胺651、酚醛胺和促进剂DMP-30为原料,制备了一种高粘接性能、双组分室温固化环氧胶。研究了DMP-30的用量对环氧胶适用期的影响;R-1000、KH-560的用量和A、B组分配比对环氧胶粘接性能的影响。结果表明,m₍聚酰胺+酚醛胺/m_DMP-30=100/12时,环氧胶的适用期为40～45min;m_E-51/m_R-1000=100/16、m_E-51/m_KH-560=100/2,m_A/m_B=3.0/1.0时,环氧胶的粘接性能最佳。     

Mechanical properties and chemical bonding characteristics of WC and W2C compounds

The mechanical properties and chemical bonding features of W–C binary compounds (h-WC, o-W₂C, h-W₂C and t-W₂C) were studied by density functional theory (DFT). It is shown that they are thermodynamically stable identified by the cohesive energy and formation enthalpy of W–C binary compounds. The elastic constants were calculated using the stress–strain method. The Voigt–Reuss–Hill approximation was used to evaluate the moduli. The surface constructions of bulk and Young's moduli were applied to illustrate the mechanical anisotropy. The population analysis of W–C binary compounds was used to discuss the chemical bonding, which indicate the combinations of covalent and metallic bonds in these compounds. Moreover, the anisotropic properties of sound velocities for W–C binary compounds were explored.     

废EPS改性制备清香型乳液胶粘剂及粘接应用研究

以MAA(甲基丙烯酸)和PVA(聚乙烯醇)为主要原料,以BPO(过氧化苯甲酰)为引发剂,以乙酸乙酯、丙酮和废弃橙皮精油作为废EPS(聚苯乙烯泡沫塑料)的混合溶剂,制备了清香型废EPS改性胶粘剂。研究结果表明:当混合溶剂中V(乙酸乙酯)∶V(废弃橙皮精油)∶V(丙酮)=5∶3∶2时,其对废EPS的溶解力(8.20 g/10 mL)最强;采用正交试验法优选出制备废EPS改性胶粘剂的最佳工艺条件为w(EPS中MAA)=8%、w(EPS中BPO)=3%、反应温度70℃和w(胶液中PVA)=10.0%,此时改性胶粘剂胶接实木单板的剪切强度可达到0.825 MPa,并且其对织物纤维、纸张等胶接性能良好。     

Supermolecular structure and mechanical properties of P(AN-AM-AA)/PVA intermacromolecular complex formed through hydrogen bonding

In this article the supermolecular structure and mechanical properties of poly(acrylonitrile-acrylamide-acrylic acid)/poly(vinyl alcohol) [P(AN-AM-AA)/PVA] intermacromolecular complex formed through hydrogen bonding were studied by means of SEM, TEM, and mechanical property testing. The experimental results show that fibrous or network structure could be formed in P(AN-AM-AA)/PVA intermacromolecular complex, and this unique supramolecular structure endows the material with much superior mechanical properties to its constituents. The tensile strength of P(AN-AM-AA)/PVA complex is as high as 3 times that of PVA, and the Young's modulus of the complex is almost 6 times that of PVA. All the encouraging results demonstrate that intermacromolecular complexation among the polymers having complementary structures is an innovative strategy to reinforce polymer materials and, therefore, to prepare a new kind of microcomposites. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 2089–2096, 1997