纳米二氧化硅表面改性及增强聚氨酯密封胶

采用不同硅烷偶联剂对纳米二氧化硅表面进行改性,探讨了不同纳米二氧化硅含量对聚氨酯密封胶力学性能的影响。研究结果表明:使用γ-(甲基丙烯酰氧基)丙基三甲氧基硅烷对二氧化硅表面改性,可得到分散均匀的球形纳米二氧化硅粒子;将改性后的纳米二氧化硅加入聚氨酯密封胶中,产品的力学性能有明显提高。     

新溶剂体系应用研究(四):在聚氨酯涂料生产与施工中的应用

新溶剂体系是指由甲氧基乙酸甲酯、醋酸仲丁酯、甲氧基乙酸仲丁酯共同构成的溶剂体系。介绍了该新溶剂体系在芳香族丙烯酸聚氨酯磁漆和脂肪族丙烯酸聚氨酯磁漆中的应用研究结果。结果表明:在2类聚氨酯磁漆制漆中,都可以用新溶剂体系替代现有溶剂;在2类聚氨酯磁漆的稀释剂中,都可以用醋酸仲丁酯、甲氧基乙酸仲丁酯按一定比例的混合溶剂,替代现有的稀释剂,比例为m(醋酸仲丁酯)∶m(甲氧基乙酸仲丁酯)=8∶2;用醋酸仲丁酯、甲氧基乙酸仲丁酯可替换固化剂中的兑稀溶剂,和原配方固化剂的各项指标基本一致。     

有机硅改性丙烯酸聚氨酯涂料的制备

以过氧化二苯甲酰为引发剂,将不同用量的γ-甲基丙烯酰氧基丙基三甲氧基硅烷与苯乙烯、丙烯酸酯类单体进行共聚,合成有机硅改性含羟基丙烯酸树脂。红外光谱证实有机硅成功地引入到丙烯酸树脂中。用该有机硅改性树脂与N3390固化剂反应,制成有机硅改性聚氨酯涂料,考察了有机硅含量对漆膜性能的影响。     

在聚氨酯涂料生产与施工中的应用

新溶剂体系是指由甲氧基乙酸甲酯、醋酸仲丁酯、甲氧基乙酸仲丁酯共同构成的溶剂体系.介绍了该新溶剂体系在芳香族丙烯酸聚氨酯磁漆和脂肪族丙烯酸聚氨酯磁漆中的应用研究结果.结果表明:在2类聚氨酯麟漆制漆中,都可以用新溶剂体系替代现有溶剂;在2类聚氨酯磁漆的稀释剂中,都可以用醋酸仲丁酯、甲氧基乙酸仲丁酯按一定比例的混合溶剂,替代现有的稀释剂,比例为m(醋酸仲丁酯):m(甲氧基乙酸仲丁酯)=8:2;用醋酸仲丁酯、甲氧基乙酸仲丁酯可替换固化剂中的兑稀溶剂,和原配方固化剂的各项指标基本一致.     

硅酮粉对改性PC体系的耐划伤性能的研究

主要用硅酮粉对已用质量分数为5%的晶须硅改性后的聚碳酸酯(PC)体系进行了抗划伤改性;测定了改性后PC体系的热力学、力学、流变和耐划伤性能。通过比较和分析试验数据,得出了硅酮粉对PC+5%晶须硅体系耐划伤改性的最佳配方即PC+5%晶须硅+1%硅酮粉。     

γ-环氧丙氧基丙基三甲氧基硅烷改性聚氨酯弹性体的合成、结构与性能

以聚氧化丙烯二元醇(PPG-1000)、甲苯二异氰酸酯(TDI)为主要原料,γ-环氧丙氧基丙基三甲氧基硅烷(KH-560)为有机硅改性剂,合成了KH-560改性聚氨酯预聚物。采用3,3′-二氯-4,4′-二氨基-二苯基甲烷(MOCA)为扩链剂,制备了新型有机硅改性聚氨酯弹性体。考察了KH-560用量及不同加料顺序对改性聚氨酯弹性体力学性能的影响,并用傅里叶变换红外光谱法对KH-560改性聚氨酯预聚体的结构进行了表征,对KH-560化学改性聚氨酯弹性体的反应机制进行了初步探讨。结果表明,KH-560中环氧基团参与了化学反应生成了—OH,并将有机硅氧烷结构单元以化学键合的方式引入了聚氨酯主链结构中;当PPG-1000和TDI用量不变时,加入KH-560提高了软链段的含量,并且形成的支链结构破坏了聚氨酯主链的规整性。改性聚氨酯弹性体的力学性能随着KH-560用量的增大而显著降低。     

表面湿法改性CaSO4晶须在RTV硅酮密封胶中的应用研究

为改善单组分室温硫化(RTV)硅酮密封胶强度较低的缺点,采用γ-氨丙基三乙氧基硅烷(KH-550)对硫酸钙晶须进行表面湿法改性。将改性CaSO4晶须加入RTV硅酮密封胶中,制备了高性能的RTV硅酮密封胶。阐述了KH-550改性CaSO4晶须的机理,考查了KH-550用量、改性温度以及改性时间对改性效果的影响。探讨了改性CaSO4晶须对RTV硅酮密封胶工艺性、硬度以及力学性能的影响。结果表明,当m(KH-550)=3%、改性温度90℃、改性时间30min时改性效果最佳。改性CaSO4晶须的活化指数可达到80%以上。CaSO4晶须的添加量越多,RTV硅酮密封胶的挤出性越差;当改性CaSO4晶须质量分数8%时,对密封胶硬度的改性效果最佳。当改性CaSO4晶须质量分数为4%～5%时,制备的胶粘剂拉伸强度、剪切强度和断裂伸长率最优。     

有机硅偶联剂改性聚氨酯密封胶研究进展

对聚氨酯(PU)密封胶、硅酮密封胶、有机硅偶联剂改性PU密封胶各自的性能、特点作了对比分析,介绍了有机硅偶联剂改性PU预聚体的合成方法以及合成原料对密封胶性能的影响。     

PET薄膜用水性聚氨酯涂料的改性研究

用丙烯酸乳液对水性聚氨酯进行改性,研制出用于聚对苯二甲酸乙二醇酯(PET)薄膜表面的涂料。测试了涂料黏度、固含量、玻璃化转变温度等基本性能,用红外光谱表征了水性聚氨酯、丙烯酸乳液及改性聚氨酯的结构特征,用划格法表征了改性聚氨酯和未改性聚氨酯涂层与PET板材附着力等级。结果表明:改性聚氨酯涂料的固含量较未改性相比有小幅提高;改性聚氨酯的起始分解温度为210℃,外延起始温度为373℃,与未改性相比分别提高了50℃和63℃;改性聚氨酯涂料在PET板材表面的附着力比未改性时提高了一个等级。     

硅酮粉改性超高分子量聚乙烯及其熔体纺丝加工性能

针对超高分子量聚乙烯（PE-UHMW）熔体加工性能差的问题,应用硅酮粉,采用熔融共混方法对PE-UHMW进行改性,以提高其熔体加工时的流动性。通过扫描电子显微镜与能量色散谱（EDS）表征了硅酮粉在PE-UHMW中的分布,并采用熔体速率测试、旋转流变测试,分析了硅酮粉含量对PE-UHMW熔体流动速率与流变性能的影响。对改性后的PE-UHMW采用熔体纺丝法制备了PE-UHMW单丝,并进行了拉伸强度测试。实验结果表明,随着硅酮粉的增加,其分散性逐渐变差,PE-UHMW熔体流动速率随硅酮粉含量先增加后降低,当硅酮粉质量分数达到4%,其熔体流动速率最高,复数黏度与储能模量最低,5%质量分数的硅酮粉在PE-UHMW基体中团聚较明显,改性后的PE-UHMW熔体流动性降低。熔体纺丝实验结果表明改性后的PE-UHMW可以通过普通单螺杆挤出机熔融挤出初生丝,经超倍热拉伸可以制备高强度单丝。当拉伸倍率为36时,质量分数3%的硅酮粉改性PE-UHMW单丝拉伸强度最高,可达1 565 MPa。因此综合考虑加工性能与单丝强度,采用质量分数3%的硅酮粉改性PE-UHMW较合适。     

有机硅改性无溶剂阳离子型聚氨酯/丙烯酸酯复合乳液的制备

以异佛尔酮二异氰酸酯(IPD I)、聚四氢呋喃二醇(PTMG 1000)、N-甲基二乙醇胺(MDEA)、三羟甲基丙烷(TMP)等为主要原料,通过硅烷偶联剂γ-氨丙基三乙氧基硅烷(KH550)封端改性,制备了无溶剂阳离子型聚氨酯/丙烯酸酯核壳乳液表面施胶剂(PAU)。通过红外光谱(FTIR)、热重分析(TG)、X射线衍射分析(XRD)、透射电镜(TEM)、力学性能等对其结构与性能进行了表征及测试。结果表明,当n(—NCO)∶n(—OH)=1.07∶1,m(St)∶m(BA)=1∶2,w(MDEA)=5.50%(占所有单体质量的总和,下同),w(TMP)=0.55%,w(KH550)=0.69%时,合成的聚氨酯有良好的力学性能与施胶性能,而且有机硅的加入增强了膜的柔韧性。     

阳离子水性聚氨酯的耐水性研究

通过正交法研究了多元醇、亲水基团含量、交联剂和扩链剂对胶膜吸水率的影响,分别对用丙烯酸酯、环氧树脂和羟基硅油改性的阳离子水性聚氨酯的耐水性进行了研究.实验结果表明,对阳离子水性聚氨酯耐水性影响因素从大到小排列依次是多元醇、亲水基团含量、交联剂和扩链剂.对阳离子水性聚氨酯进行改性能够提高其耐水性.     

A novel alkoxysilane‐modified high solids hydroxyl acrylic polyurethane: Preparation and surface properties

Alkoxysilane‐modified high solids hydroxyl acrylic polyurethane was prepared by solution polymerization. Its structure, surface, and thermal properties were investigated by ¹H NMR, device of contact angle, thermo gravimetric analysis (TGA), atomic force microscopy (AFM), and X‐ray photoelectron spectroscopy (XPS). Research showed that alkoxysilane modified high solids hydroxyl acrylic polyurethane has superior properties that can be used for automotive paints. The contents of silicone in the alkoxysilane‐modified high solids hydroxyl acrylic polyurethane were 1.25, 1.5, 2, and 2.5 wt %. In this study, γ‐methacryloxypropyltrimethoxysilane (MPTS) was chosen as the modifier. Results showed that the contact angles of water and surface roughness on the film of MPTS modified high solids hydroxyl acrylic polyurethane increased, and thermal stability of the film at high temperatures improved with the increasing of the silicone content in the resins. MPTS modified high solids hydroxyl acrylic polyurethane with 2.5 wt % silicone content had better water resistance, better acid resistance, higher hardness, and excellent weatherability. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1866–1871, 2006     

高性能水性UV固化聚氨酯的合成与性能研究

用环氧丙烯酸酯(EA)、羟基硅油合成了环氧/有机硅改性水性光固化聚氨酯乳液(WPU);研究了EA、羟基硅油、亲水扩链剂二羟甲基丁酸(DMBA)的用量,中和度和硅烷偶联剂的添加量对乳液和涂膜性能的影响。用红外光谱和接触角测量仪对树脂进行表征。结果表明:通过EA、羟基硅油改性的水性光固化聚氨酯涂膜的硬度高、附着力强、耐水性较好,克服了未改性水性光固化聚氨酯的缺点。当EA用量为4%、羟基硅油为2%、DMBA为8%、中和度为80%、硅烷偶联剂的添加量为1%时,水性光固化聚氨酯乳液的综合性能较好,树脂接触角大大提高。     

硅氧烷改性聚氨酯密封胶的研究

利用硅氧烷封端对聚氨酶进行改性得SPU预聚体，进而制备出硅烷化聚氨酯密封胶，然后对其性能进行了测试并与其他产品进行对比。结果表明：改性后的产物在粘接性、耐热性、耐湿热性、贮存稳定性及某些力学性能上综合了硅酮和聚氨酶的优点，又避免了各自的部分缺点。是一种新型建筑密封材料。     

我国改性聚氨酯的研究现状

综述了我国改性聚氨酯的主要分类,重点介绍了环氧树脂改性聚氨酯、聚丙烯酸酯改性聚氨酯、无机碳纳米管改性聚氨酯、有机硅改性聚氨酯等的研究进展,最后指出了我国改性聚氨酯今后发展方向。     

高含量有机硅改性水性聚氨酯乳液的制备及性能研究

合成了高有机硅含量的水性聚氨酯稳定乳液。测量了有机硅含量对水接触角的影响,并对乳液的稳定性、黏度及涂膜的FT-IR、DSC、机械性能等进行了表征。     

Surface and mechanical properties of an organic-inorganic super- hydrophobic coating using modified nano-SiO2 and mixing polyurethane emulsion as raw materials

A series of organic-inorganic super-hydrophobic coatings were prepared using nano-SiO₂ particles modified by fluorine and silicone coupling agents, and a mixing polyurethane emulsion as main raw materials. The mixing polyurethane emulsion was consisted of the polyurethane emulsion end-terminated by double bond (WPUD) and polyurethane emulsion modified by silicone (WPUS). The influence of content of modified nano-SiO₂ particles and the weight ratio of WPUS to WPUD on microstructure and hydrophobicity of the coating surface were studied. The morphologies of coating surface were examined using SEM and AFM, hydrophobicity of the coating was researched by examining static water contact angle and so on. It was found that modified nano-SiO₂ particle was an indispensable factor during the preparation of super-hydrophobic coating. The roughness and hydrophobicity of the coating surface were enhanced obviously with an increase of the content of the modified nano-SiO₂ particles. When the content of the modified nano-SiO₂ particles increased up to 1.5%, the surface of coating possessed good super-hydrophobicity, and static water contact angle reached 169.1°. It was also noticed that the weight ratio of WPUS to WPUD in the base layer has also an important influence on the hydrophobicity and mechanical property of coating surface. With an increase of the ratio of WPUS to WPUD the hydrophobicity of the coating was enhanced, the tensile strength and peel strength reduced, but the elongation at break increased. When the weight ratio of WPUS to WPUD reaches up to 9/100, the static water contact angle reaches the maximum value of 169.1°.     

Improving Properties of Dynamic Vulcanized Polyurethane and Silicone Rubber Elastomer through Controlling Interphase Layer

In this work, a new kind of compatibilizer was prepared through the reaction between hyperbranched polyurethane and isocyanate-modified silicone oil and its application in the dynamic vulcanized polyurethane and silicone rubber elastomer was investigated. Compared with that of dynamic vulcanized thermoplastic polyurethane (TPU)/silicone rubber elastomer without compatibilizer, the introduction of 3% silicone-modified hyperbranched polyurethane lead to the increase in tensile strength from 8.1 to 13.9?MPa and the tear strength from 56.2 to 75.2 kN/m. The introduction of silicone-modified hyperbranched polyurethane as an interphase layer controller leads to the improvement in properties of TPU/silicone rubber elastomer.     

高导热阻燃有机硅灌封胶的制备

以乙烯基硅油、含氢硅油为基础胶料,十六烷基三甲氧基硅烷改性氧化铝为导热填料,二乙基次膦酸铝(ADP)为阻燃剂,制得导热阻燃绝缘有机硅电子灌封胶。研究了改性氧化铝用量对灌封胶黏度、导热性、阻燃性的影响,观察了燃烧残余物的形貌。结果表明,这种改性氧化铝有低吸油值,填充量对灌封胶黏度影响小,所制备的灌封胶具有良好导热性能;而ADP不仅展现出对灌封胶良好的阻燃性,而且还能与改性氧化铝产生协效阻燃性和抑烟作用,同时灌封胶也具有良好的流动性、力学性能和电绝缘性能。当ADP用量50份、改性氧化铝用量600份时,灌封胶的黏度为8 500 mPa·s,硫化后胶条的热导率达2.12 W/m·K,垂直燃烧达到FV-0级,拉伸强度1.72 MPa,拉断伸长率62%,体积电阻率3.9×1012Ω·cm。