聚氨酯丙烯酸酯/蒙脱土纳米复合材料的制备与研究

采用烯丙基三苯基氯化磷对蒙脱土(MMT)进行有机化处理,并采用熔融插层法制备了聚氨酯丙烯酸酯(PUA)/MMT纳米复合材料,探讨了改性MMT用量对PUA/MMT纳米复合材料性能的影响。结果表明,改性MMT的加入可提高复合材料的耐热性与断裂伸长率,当改性MMT的质量分数为3%时复合材料的综合性能最佳,其起始分解温度和断裂伸长率分别达到了321.8℃和96.03%。     

丁苯弹性体/蒙脱土复合材料改性老化沥青

将粉末丁苯橡胶(PSBR)或苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)与蒙脱土(MMT)制成复合材料,用于改性老化沥青(PSBR质量分数3%,SBS质量分数5%),研究了复合材料及其改性老化沥青的结构,考察了MMT用量对复合材料改性老化沥青物理性能与高温贮存稳定性的影响.结果表明,在PSBR/MMT复合材料中,MMT与PSBR形成了插层结构;在PSBR/MMT和SBS/MMT复合材料改性老化沥青中,复合材料呈球状分布;当MMT用量过大时,部分MMT滞留在聚合物中,出现颗粒MMT;复合材料对老化沥青的物理性能改性优于单独加入MMT;PSBR/MMT复合材料可改善老化沥青的高低温性能;SBS/MMT复合材料可显著改善老化沥青的高温性能;MMT用量不同时,PSBR/MMT复合材料改性老化沥青的贮存稳定性相当;当SBS/MMT(质量比)为5/3时,复合材料改性老化沥青的贮存稳定性较佳.     

原位聚合制备尼龙610/改性蒙脱土纳米复合材料的研究

采用增塑剂N-甲基苯磺酰胺对蒙脱土(MMT)进行改性,通过原位聚合法制备了尼龙(PA)610/改性MMT纳米复合材料。研究了改性MMT用量对PA610/改性MMT纳米复合材料性能的影响。结果表明,当改性MMT的质量分数为4%时,纳米复合材料的冲击强度和拉伸强度达到最大值,断裂伸长率则随着改性MMT用量的增加而降低。扫描电子显微镜观察发现,改性MMT均匀分散在PA610基体中。     

用原位有机改性法制备的溴化丁基橡胶／蒙脱土复合材料的性能

采用原位有机改性法制备了溴化丁基橡胶(BIIR)/蒙脱土(MMT)复合材料,并对其硫化特性和力学性能进行了研究,用X射线衍射仪时复合材料中MMT的层间距进行了表征,并与钠基蒙脱土(Na-MMT)、有机蒙脱土(OMMT)和BIIR形成的复合材料进行了对比.结果表明,用原位有机改性法制备的BIIR/MMT复合材料的硫化特性和力学性能优于BIIR/Na/MMT复合材料,甚至优于BIIR/OMMT复合材料;采用原位有机改性法,可使BIIR/MMT体系中MMT的插层效果明显改善.     

PLA/改性MMT复合材料的性能

以十六烷基三甲基溴化铵(CTAB)为改性剂对蒙脱土(MMT)进行改性,将其填充到聚乳酸(PLA)中,采用熔融插层法制备了PLA/改性MMT复合材料,并研究了复合材料的性能。结果表明:添加MMT可提高复合材料的阻燃性能和耐热性能;添加未改性MMT降低了复合材料的力学性能,当其用量为9 phr时,复合材料的拉伸强度从42.1 MPa降至38.6 MPa,断裂拉伸应变从4.5%降至2.2%,冲击强度从15.2 kJ/m~2降至8.6 kJ/m~2;添加适量(3~5 phr)改性MMT可提高复合材料的力学性能,当其用量为5 phr时,复合材料的拉伸强度和断裂拉伸应变均达最大值,分别为47.2 MPa和10.6%,当其用量为3 phr时,复合材料的冲击强度达最大值,为25.2 kJ/m~2。     

有机蒙脱土对低蛋白天然橡胶的补强作用研究

对片层结构的蒙脱土(MMT)进行表面改性,由改性的有机蒙脱土(OMMT)对低蛋白天然橡胶(LPNR)进行补强,采用机械混炼法制备LPNR/OMMT复合材料,研究OMMT对LPNR/OMMT复合材料性能的影响。结果表明:MMT适合采用双十八烷基二甲基氯化铵改性;随着OMMT用量增大,LPNR/OMMT复合材料的交联网络结构、物理性能、抗压缩永久变形性能和耐老化性能明显改善;当OMMT用量为8份时,复合材料的综合性能最佳。OMMT对LPNR的补强研究可以为改善LPNR的性能提供参考,有助于扩大LPNR的应用领域。     

阻隔性尼龙611／有机蒙脱土纳米复合材料的研究

以11-氨基十一酸对蒙脱土(MMT)进行有机化改性,采用原位聚合法制备了尼龙611/有机蒙脱土(OM-MT)纳米复合材料.通过傅立叶变换红外光谱仪研究了OMMT及尼龙611/OMMT纳米复合材料的化学结构,使用扫描电子显微镜观察了纳米复合材料的形貌.详细考察了OMMT含量对尼龙611/OMMT纳米复合材料阻隔性能和力学性能的影响,探讨了OMMT的阻隔机理.结果表明,MMT经有机化改性后,其片层在尼龙基体中分散均匀,并与尼龙基体发生键合作用,使尼龙611分子的内聚力增强,分子链堆积程度提高,极大地提高了阻隔性能;OMMT质量分数为3%时,材料的拉伸强度达到最大值,但在常温、低温下冲击强度略有下降.     

PVC-U/蒙脱土复合材料的制备与力学性能研究

采用聚氧乙烯-聚氧丙烯(EP)嵌段共聚物对钠基蒙脱土进行有机化处理改性,XRD测试结果表明嵌段共聚物插层进入了蒙脱土层间.用熔融共混法制备了聚氯乙烯/蒙脱土复合材料,并研究了钠基蒙脱土和EP改性的有机蒙脱土对复合材料力学性能的影响.研究结果表明,采用EP对MMT进行改性能够提高MMT与PVC之间的相容性,PVC-U/MMT-EP复合材料的力学性能得到明显提高,EP对MMT改性是制备有机改性蒙脱土的有效方法之一.     

硅橡胶/改性蒙脱土复合材料的制备及其性能研究

以双十八烷基二甲基氯化铵(D1821)改性蒙脱土(MMT),考察了室温混炼及熔融混炼对甲基乙烯基硅橡胶(MVQ)/MMT及MVQ/MMT-D1821复合材料拉伸强度、热性能及微观形貌的影响。结果表明,改性后的MMT层间距由1.25nm扩大到了3.97nm,熔融混炼比室温混炼更有利于形成插层结构,且复合材料拉伸强度更大,当MMTD1821含量为30份(质量份,下同)时,复合材料的拉伸强度最大为6.0 MPa,但材料的热性能有所降低。     

PUA抗菌材料的制备及性能研究

采用不饱和季鳞盐抗菌剂对聚氨酯丙烯酸酯(PUA)改性,制备了一种新型抗菌高分子材料.考察了抗菌剂用量对材料透光率、力学性能、玻璃化转变温度及热稳定性的影响,同时通过定量抗菌实验对材料的抗菌性能进行了测定.结果表明,季鳞盐抗菌剂对PUA成功地进行了改性,在添加质量分数为1%的抗菌剂时,材料对金黄色葡萄球菌和大肠杆菌24 ...     

Study on polyurethane-acrylate/cerium dioxide modified by 3-(Methylacryloxyl)propyltrimethoxy silane and its UV absorption property

Firstly, cerium dioxide(CeO₂) was modified by 3-(Methylacryloxyl)propyltrimethoxy silane (KH-570), and modified CeO₂ (mCeO₂) was prepared. Then poly (urethane-acrylate) was modified by mCeO₂, and poly (urethane-acrylate)/modified CeO₂ (PUA/mCeO₂) composites with ultraviolet absorption property were prepared. The morphology, thermal hydrophobicity, mechanical properties, optical properties, and UV-absorption properties of PUA/mCeO₂ composites were studied. XRD and SEM analysis showed that the modified CeO₂ had better dispersion in the matrix than that of pure CeO₂. Ultraviolet–visible spectrum and thermogravimetric analysis were used to characterize the optical properties and thermal stability of PUA/mCeO₂ composites. The results showed that with the increasing of the mCeO₂ content, the UV-absorption property of PUA/mCeO₂ composites was improved gradually. When the content of mCeO₂ is 3%, the absorption of ultraviolet of PUA/mCeO2 composites is about 5 times of pure PUA film, and the absorption band is mainly in the UVA section. The thermal stability of PUA/mCeO₂ composites was improved with the adding of mCeO₂. With the increasing of mCeO₂ content, the contact angle of PUA/mCeO₂ composites increased significantly. And the UV-absorption mechanism of PUA/mCeO₂ Composites was studied. UV-curable PUA/mCeO₂ composites have good UV absorption property and water resistance. They will be used in the sun screen and protect people's skin.     

聚丙烯/BA原位聚合改性MMT纳米复合材料的DSC分析与力学性能

通过原位聚合制备了聚丙烯酸丁酯 (PBA )改性蒙脱土 (MMT ) ,与聚丙烯 (PP)熔融复合制成PP/MMT纳米复合材料 ,系统地研究了复合材料的熔融、结晶行为和力学性能。结果表明 :随着处理MMT的BA用量的增加 ,PP/MMT纳米复合材料中PP相的结晶度、熔点和结晶温度明显提高 ,结晶速度加快 ;复合材料的拉伸强度变化不大 ,但拉伸模量和冲击强度有显著提高。当BA/OMMT质量比为 1/ 12左右时 ,复合材料的韧性趋于平衡值 ,而拉伸模量出现最大值     

PP/MMT复合材料的制备与性能研究

以聚丙烯(PP)回收料为基体,改性蒙脱土(MMT)为填充剂,通过熔融共混的方法制备了PP/MMT复合材料,探讨了MMT用量对PP/MMT复合材料的热行为、机械性能及流动性能的影响。结果表明:少量MMT的加入可明显提高复合材料的力学性能,其拉伸强度提高26%,断裂伸长率提高520%,冲击强度提高11%。MMT的加入可提高复合材料的结晶温度,但对其熔点的影响不大;随着MMT的添加,PP/MMT复合材料的流动性能得到了很好的改善,当MMT的含量为1 wt%时,其熔融指数达到最大值,体系的粘度变小。     

丙烯酸酯类聚氨酯/SiO2纳米复合材料制备及性能研究

用原位聚合法制备丙烯酸酯类聚氨酯/SiO2纳米复合材料,通过透射电子显微镜研究了纳米SiO2在基体中的分散情况,并对材料的力学性能和光学性能进行了研究。结果表明,纳米SiO2在基体中分散很好;当纳米SiO2的质量分数为1.5%时,复合材料的综合力学性能最佳,其拉伸强度、断裂伸长率和冲击强度分别为34.20MPa、56.15%和81.52kJ/m2,与纯丙烯酸酯类聚氨酯相比分别提高了52.75%、81.19%和149%;且该复合材料的透光率在80%以上。     

Preparation and characterization of polypropylene/clay nanocomposites with polypropylene‐graft‐maleic anhydride

Polypropylene (PP)/montmorillonite (MMT) nanocomposites were prepared by the esterification of propylene‐g‐maleic anhydride (MAPP) with MMT modified with α,ω‐hydroxyamines. The structural characterization confirmed the formation of ester linkages and the interaction between the silicate layers. In particular, X‐ray diffraction patterns of the modified clays and MAPP/MMT composites showed 001 basal spacing enlargement as great as 0.14–0.62 nm according to the type of α,ω‐hydroxyamine. Thermal characterization by thermogravimetric analysis for the composites revealed increased onset temperatures of thermal decomposition. The melting peak temperature decreased, and the crystallization peak temperature increased; this indicated that MMT retarded the crystallization of MAPP. Compounding PP with MAPP/MMT composites enhanced the tensile modulus and tensile strength of PP. However, the elongation at break decreased drastically even when the MMT content was as low as 0.4–2.0 wt %. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1229–1234, 2005     

ECAE加工对PP/MMT复合材料结构和性能的影响

研究了聚丙烯/蒙脱土(PP/MMT)复合材料经等通道转角挤压(ECAE)加工后的结构与性能,并探讨了MMT的变形和分散机理。结果表明,ECAE加工的巨大剪切力不仅能使PP/MMT复合材料的基体产生取向,而且还可使团聚的MMT粒子在基体中变形、取向、分散和尺寸减小,且二次ECAE加工对MMT粒子的分散效果更加显著;PP/MMT复合材料经一次ECAE加工后试样的缺口冲击强度有所提高,而经二次ECAE加工后试样的冲击强度显著提高,其中含2%MMT的ECAE-PP/MMT-A试样的缺口冲击强度达到了93.1kJ/m2,为纯PP的19倍。     

PEN／MMT纳米复合材料结晶动力学的研究

采用熔融插层法制备聚2,6-萘二甲酸乙二酯(PEN)/蒙脱土(MMT) 纳米复合材料,用Avrami方程和张志英方法对所得数据进行了等温结晶和非等温结晶动力学的研究.结果表明,在PEN/MMT共混物中由于MMT的加入,降低了PEN/MMT的结晶活化能,导致共混物的结晶速率提高;MMT含量影响共混物的结晶速度,加入少量的MMT可以明显提高共混物的结晶速率;共混物的表面活化能的变化与Avrami方程得出的n值变化相似,MMT的含量影响共混物成核结晶速度.     

Structure‐property and swelling behavior of electron beam irradiated poly(vinyl alcohol)/acrylamide/sodium montmorillonite clay composites

Composites based on poly(vinyl alcohol) (PVA), acrylamide monomer (AM) and sodium montmorillonite clay (MMT) were prepared, in the form of thin films, by solution casting. The PVA/AM/MMT composites films were then exposed to electron beam irradiation to form crosslinked network structure. The structure‐property behavior of PVA/AM/MMT hybrids was demonstrated by x‐ray diffraction (XRD), scanning electron microscopy, gel content, color intensity, thermogravimetric analysis (TGA) and swelling behavior in aqueous solutions. The results indicated that the introduction of MMT clay ratio up to 5% decreased the gel content of PVA/AM hydrogels. The color measurements indicated that the introduction of MMT clay ratio up to 5% was shown to affect the color intensity of composite films. It was found that both PVA/AM hydrogels and PVA/AM/MMT composites reached the equilibrium swelling state in water after four hours; however PVA/AM/MMT composites displayed higher swelling than PVA/AM hydrogels. However, the swelling of PVA/AM hydrogels or their composites at the equilibrium state increased with increasing temperature up to 60°C. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Preparation and Characterization of Organically Modified Montmorillonite-Filled High Density Polyethylene/Hydroxyapatite Nanocomposites for Biomedical Applications

The study investigated the introduction of organically modified montmorillonite (MMT) in high density polyethylene/hydroxyapatite (HDPE/HA) composites for biomedical applications. The addition of HA and MMT increased the strength and stiffness of HDPE/HA composites with deterioration in impact strength and elongation at break values. XRD and TEM analysis provided evidence of exfoliated MMT layers in HDPE/HA composites and the MMT layers remained exfoliated even with further addition of HA. Simulated body fluid (SBF) analysis revealed that the size of apatite layer increased with increasing immersion time and the formation of apatite layers on the surface of composites indicates excellent biocompatibility properties.