聚丙烯／蒙脱土纳米复合材料流变性能及抗紫外性能的研究

采用毛细管流变仪和熔融指数测定仪对聚丙烯／蒙脱土纳米复合材料的流变性能进行了研究，讨论了复合材料的熔融指数、非牛顿指数、表观粘度及粘流活化能与组成之间的关系。考察了复合材料的抗紫外性能。结果表明：复合材料流体为假塑性流体，其表观粘度对剪切速率的依赖性随纳米蒙脱土质量分数的增大而变小；复合材料的表观粘度随纳米蒙脱土质量分数的增加而逐渐增大，纳米蒙脱土的加入对体系流动有一定的阻碍作用；随着纳米蒙脱土质量分数的增大，复合材料对紫外光的屏幕效果越来越强。     

高吸水纳米复合材料的制备与应用性能研究

采用反相乳液聚合方法,在体系中引入蒙脱土,制备高吸水树脂Poly(AA-co-AM)和高吸水纳米复合材料MMT/Poly(AA-co-AM).用IR、XRD、SEM表征高吸水树脂和高吸水纳米复合材料的结构与形态;考察交联剂用量、蒙脱土用量对高吸水纳米复合材料吸水能力的影响;重点研究蒙脱土的引入对产物粒子形态和吸液能力的影响.结果显示:蒙脱土完全剥离且均匀地分散在聚合物中;与高吸水树脂相比,高吸水纳米复合材料的粒径更小,表面凹凸不平且充满褶皱;高吸水纳米复合材料的吸水倍率、吸盐水倍率、保水性能都增大,但其饱和吸水时间变长;吸水能力随着交联剂、蒙脱土用量的增大均呈先增后减的趋势;蒙脱土质量分数为3%时,吸水倍率达1 264 g/g.     

改性剂对EVOH/蒙脱土纳米复合材料 性能影响的研究

对双十八烷基二甲基氯化铵改性后的蒙脱土进行红外(FTIR),X射线(XRD),扫描电镜(SEM)表征;同时采用偶联剂对有机蒙脱土进行二次改性,然后用溶液插层法制备了EVOH/蒙脱土纳米复合膜,并对复合膜性能进行测试.结果表明:改性后的蒙脱土表面由亲水变为疏水,层距由1.470 am增大到3.529 nm;而用质量分数为5%的硅烷偶联剂KH550改性的有机蒙脱土与EVOH制得的复合膜力学性能、阻隔性能得到了较好的提高,同时复合膜的透明性没受到影响.     

配位插层法制备酚醛树脂/蒙脱土纳米复合材料的性能研究

利用单体配位插层法制备酚醛树脂/蒙脱土纳米复合材料,并对不同蒙脱土含量的复合材料在软化点、粘结剪切强度和热稳定性方面与纯酚醛树脂进行比较.结果表明：当蒙脱土质量分数为2 %～5 %时,复合材料的软化点变化不明显;不同蒙脱土含量的酚醛树脂/蒙脱土纳米复合材料的粘结剪切强度均高于纯酚醛树脂;在温度低于300 ℃和温度高于400 ℃时复合材料在热稳定性方面均优于纯酚醛树脂.     

PVC/蒙脱土复合材料的制备与性能研究

用乳液聚合的方法制备聚甲基丙烯酸甲酯(PMMA)/蒙脱土纳米复合材料.XRD分析表明PMMA嵌入了蒙脱土层间.使层间距明显扩大.用熔融共混的方法制备PVC/有机化蒙脱土复合材料并对其结构、力学性能、流变性能进行研究,证明该纳米复合材料能有效提高PVC的力学性能.     

PE/MMT纳米复合材料制备及热性能

为了制备PE/MMT纳米复合材料,探讨其优异的热性能,利用不同种类的醇和内给电子体制备出有机蒙脱土负载的Ziegler-Natta催化剂,利用原位聚合法合成了PE/MMT纳米复合材料,并通过比较得出了PE/MMT纳米复合材料合成的最佳工艺条件.借助于红外光谱和扫描电镜对其结构进行了表征,利用热重分析法分析了其热性能.研究结果表明,PE/MMT纳米复合材料的最佳工艺条件是正丁醇与异辛醇的摩尔比为2∶0.8.当内给电子体为正硅酸乙酯且蒙脱土的质量分数为1.1%时制备出的PE/MMT纳米复合材料具有较好的热性能.     

酚醛树脂/偶联剂改性蒙脱土的制备及性能研究

分别通过水解法和非水解法制备了硅烷偶联剂KH-560改性蒙脱土,并合成了酚醛树脂/改性蒙脱土纳米复合材料。采用傅里叶红外光谱(FTIR)、X射线衍射(XRD)对蒙脱土结构进行了表征,通过透射电镜(TEM)和热重分析(TG)研究了酚醛树脂/有机蒙脱土纳米复合材料的结构和热性能。TEM测试发现非水解法改性蒙脱土可与酚醛树脂形成剥离纳米结构,而水解法改性蒙脱土与酚醛树脂形成了剥离和插层的复合结构;TG分析显示2种改性蒙脱土均可提高酚醛树脂的热性能。     

无皂乳液聚合制备PMMA／MMT纳米复合材料的研究

采用离子交换法,用溴化烯丙基三乙基铵对钠基蒙脱土进行改性制备了有机蒙脱土,再以甲基丙烯酸甲酯（MMA）为单体,过硫酸钾为引发剂,通过无皂乳液聚合制备聚甲基丙烯酸甲酯朦脱土（PMM-MMT）纳米复合材料。采用傅里叶变换红外（FTIR）、X-射线衍射（XRD）和扫描电镜（SEM）等手段对有机蒙脱土和复合材料的结构进行表征。结果表明：溴化烯丙基三乙基铵成功插层到蒙脱土层间,层间距由1．32nm增大到1．44nm;FTIR和XRD测试结果表明不同蒙脱土含量的PMMA/MMT纳米复合材料均具有剥离型结构;SEM测试结果表明PMMA/MMT纳米复合粒子的粒径随蒙脱土含量的增加而减小。     

蒙脱土/尼龙6复合材料的阻燃性能和力学性能

通过挤出注塑的方法制备了尼龙6(PA6)/蒙脱土插层复合材料,并考察了材料的阻燃性能和力学性能。结果表明,红磷加入PA6/OMMT复合材料后,无熔滴现象并且阻燃级别达到FH-1;当有机蒙脱土用量为质量分数5%~7%时,该复合材料的综合性能较好。     

四官能基环氧树脂／蒙脱土纳米复合材料的制备及表征

采用阳离子交换的方法对蒙脱土进行了有机化改性,并制备了环氧树脂／蒙脱土纳米复合材料．用FT-IR和XRD研究了环氧树脂／蒙脱土纳米复合材料的结构,并测试了纳米复合材料的性能．实验结果表明,改性使蒙脱土层间距变大,纳米复合材料的力学性能与纯环氧树脂相比提高了50％．     

蒙脱土改性核壳乳液的制备及其成膜防水性能

以甲基丙烯酸甲酯、丙烯酸正丁酯、甲基丙烯酸为聚合单体,有机蒙脱土（OMMT）为改性剂,采用原位插层聚合制备了一系列软核硬壳型核壳乳液,并研究了OMMT的添加方式及添加量对乳液粒径、凝聚率、固含量、稳定性以及乳液膜的防水性能的影响。结果表明,OMMT的添加量和添加方式对乳液粒径、凝聚率、固含量、稳定性等基本性能影响不大;当有机蒙脱土被添加在核壳乳液的核层时,乳液膜的防水性能最佳,原因是核层的玻璃化温度较低,层状OMMT在其中分散更好,增大了水分子扩散的路径;随着OMMT含量的增加,乳胶膜防水性能呈现先增长后下降的趋势,这说明少量OMMT可以分散于膜中提高防水性,而过量的OMMT易团聚反而降低了乳胶膜的防水性能。     

Property and Degradation Characteristics of Concrete Prepared with Aggregate Contained Montmorillonite

To evaluate the property and degradation characteristics of concrete prepared with aggregate contained montmorillonite, concretes were prepared with aggregates contained montmorillonite, and then concrete slump loss, compressive strength, electric flux, the resistance to carbonization, freezing-thawing and sulfate attack were evaluated. The results show that montmorillonite appearance alters concrete slump loss and compressive strength. But montmorillonite increases electric flux and compactness. The carbonization, freezingthawing and sulfate attack results indicate that montmorillonite enhances carbonization depth, increases mass loss after 300 cycle freezing-thawing, as well as mass loss after sulfate attack. Overall, it is adverse to the concrete resistance to the carbonization, freezing-thawing and sulfate attack.     

PET／蒙托土纳米复合材料的结晶行为

用示差扫描量热计（ＤＳＣ）研究了ＰＥＴ／蒙托土纳米复合材料的结晶行为,并与未填充ＰＥＴ进行了比较。结果表明：分散在ＰＥＴ基体中的蒙托土纳米微粒对ＰＥＴ的结晶具有异相成核作用;但蒙托土微粒表面与ＰＥＴ之间很强的界面作用限制了ＰＥＴ分子链段的运动,使晶体生长受到阻碍;因此总结晶速率取决于两方面的综合效应。ＰＥＴ／蒙托土纳米复合材料的结晶完善程度变差,熔点和熔融热下降,同时结晶活化能明显增大。     

Preparation and Properties of Phenolic Resin/Montmorillonite Intercalation Nanocomposites

1　IntroductionIntercalationcompoundingisoneoftheeffectivemethodstopreparepolymerbasecompositeswithexcellentproperties .Thepolymercanbeintercalatedintotheinor ganicmaterialswithlayeredstructures ,especiallysilicateclay ,throughintercalationcompoundingtoformthepoly merlayeredinorganicintercalationcomposites[1] .Amongmanylayeredsilicateclays ,montmorillonite (MMT)isof tenusedtopreparetheintercalationcomposites .MMTisasilicateclaymineralabundantinthenaturalworld .Itbe longsto 2∶1layeredsilica…     

挤出插层法制备NBR/蒙脱土纳米复合材料的研究

采用独创的挤出插层复合法成功地制备了NBR／蒙脱土纳米复合材料，并研究了其亚微观结构与性能的关系。通过红外光谱和X射线衍射分析了改性蒙脱土的特性，通过透射电子显微镜证实和分析了该复合材料的纳米分散结构。研究结果表明：蒙脱土对丁腈橡胶有明显的补强作用，并远高于同量炭黑的补强作用，而且在蒙脱土用量较小时这种作用更为显著。     

聚丙烯/聚丙烯接枝丙烯酸/蒙脱土纳米复合材料的制备及性能

用悬浮接枝法制备了接枝率为2 2%的聚丙烯接枝丙烯酸作为相容剂,用十六烷基三甲基溴化铵对钠基蒙脱土进行了有机化处理,使蒙脱土的层间距从1 2nm增加到了3 84nm。通过熔融插层法制备了插层型聚丙烯/蒙脱土纳米复合材料(Polypropylene/MontmorilloniteNanocomposites,PNC),复合材料中蒙脱土层间距比有机蒙脱土的层间距又有小幅度的增加。当蒙脱土含量为2%,相容剂用量为15%时的复合材料力学性能最好,缺口冲击强度和拉伸强度分别达到12 12kJ/m2和35 77MPa,分别比纯1PP增加了180%和4 3%,蒙脱土的加入起到了增韧和增强的双重作用。     

Residual monomer content and its release into water from the denture base nanocomposite using organic montmorillonite as reinforcement

A novel kind of denture base nanocomposite was prepared by polymethyl methyacrylate（PMMA） and cethyltrimethylammonium bromide modified organic montmorillonite （OMMT）. The dispersion of montmorillonite in the polymer matrix was characterized by x-ray diffraction （XRD） and transimission electron microscope （TEM）.The content of residual MMA in nanocomposites and the amount of MMA released to water from nanocomposites were determined by gas chromatography （GC）. The analysis of TEM and XRD showed that exfoliated-intercalated and intercalated nanocomposites were formed when the content of OMMT was 3% and 5% in the PMMA powder respectively. The results of GC showed that the residual MMA increased with the increase of OMMT content in the polymer matrix. After 7 days in water, the amount of MMA released into water from the nanocomposites tended to be stable. The results of one-way ANOVA and t-test showed that OMMT gave a significant increase of residual MMA concentration （p〈0.05） in nanocomposites.     

Experimental study of a micro-scale solar organic Rankine cycle system based on compound cylindrical Fresnel lens solar concentrator

In the present study, a micro-scale solar organic Rankine cycle power generation system was developed. The system comprises of a solar collection system based on compound cylindrical Fresnel lens concentrator and an organic Rankine cycle power generation system integrated with a scroll expander. YD320 and R245 fa were used as the heat transfer fluid and the working fluid, respectively. The effects of the evaporation pressure, the degree of superheat, and the mass flow rate of the working fluid were analyzed to evaluate the solar collection efficiency, the electric power output, the thermal efficiency and exergy efficiency of the system. The results illustrate that both the increasing evaporation pressure and decreasing superheat degree have positive impacts on solar collection efficiency. The electric power increases as the evaporation pressure increases, while the thermal efficiency and the exergy efficiency decrease. However, the system overall efficiency decreases slowly due to the increase of solar collection efficiency. The electric power increases with the increment of the working fluid mass flow rate. The increasing mass flow rate has no visible impact on the thermal and exergy efficiencies of organic Rankine cycle subsystem, whereas a slightly increase of the thermal and exergy efficiencies of the integrated system. The electric power decreases with the increase of the superheat degree, whereas the thermal and the exergy efficiencies of the system increase. The system works more suitably with a higher degree of superheat for the small mass flow rate condition.