纳米碳酸钙增强聚氨酯-异氰脲酸酯材料的研究

通过纳米碳酸钙(nano-CaCO3)分散方法及其聚氨酯-异氰脲酸酯(PUI)基础配方的研究,采用原位聚合方法研制了nano-CaCO3增强PUI材料,并对其性能进行了研究,结果表明,以n(NCO)/n(OH)配比为10∶1,催化剂为DMP-30、其用量为2%(质量分数,下同)的PUI配方为基础,利用超声辐照技术将nano-CaCO3分散于液化MDI中原位聚合所制的材料,不仅拉伸强度和撕裂强度得到显著提高,而且热稳定性也得到明显提高,当nano-CaCO3质量分数为8%时,材料的综合性能最优。     

PUI/nano-CaCO3弹性体的合成及性能研究

采用原位聚合方法合成了聚氨酯-异氰脲酸酯(PUI)/nano-CaCO3弹性体材料,并对其组成及性能进行了研究。结果表明,当PUI配方中NCO/OH摩尔比为10∶1、催化剂DMP-30质量分数为2%时,利用超声辐照技术将nano-CaCO3均匀分散于碳化二亚胺改性的液化MDI中原位聚合而成的PUI/nano-CaCO3弹性体,其力学性能和热稳定性得到明显提高,且随nano-CaCO3含量的增加而增加,当nano-CaCO3质量分数为8%时,弹性体综合性能最优。     

原位聚合聚氨酯-异氰脲酸酯／纳米SiO2材料的制备及其性能研究

通过对聚氨酯-异氰脲酸酯（PUI）基础配方的研究及其对纳米SiO2（nano-SiO2）分散方法的考察，采用原位聚合方法合成了PUI／nano-SiO2材料，并对其性能进行了研究，结果表明，以n（NCO）／n（0H）配比为10：1，催化剂为DMP-30、其用量为2％（质量分数，下同）的PUI配方为基础，利用超声辐照技术将nano-SiO2分散于液化MDI中原位聚合而成的PUI／nave-SiO2材料的力学性能和热稳定性都得到明显提高，当nano-SiO2质量分数为5％时，材料的综合性能最优。     

PUI/nano-SiO2复合材料的研制

研究了聚氨酯-异氰脲酸酯(PUI)/纳米二氧化硅(nano-SiO2)聚合物基的配方及其nano-SiO2分散方法和用量与材料性能间的关系,确定了n(NCO)/n(OH)配比为10:1,催化剂DMP-30用量为2%,利用超声辐照技术分散于液化MDI中的nano-SiO2用量为5%的原位聚合PUI/nano-SiO2的最佳配方,研制了性能优越的PUI/nano-SiO2复合材料。     

PUI/蒙脱土纳米复合材料的制备及其性能研究

考察了聚氨酯-异氰脲酸酯(PUI)的基础配方,采用原位聚合方法制备了PUI/蒙脱土(MMT)纳米复合材料,并研究了纳米蒙脱土(Nano-MMT)用量对复合材料性能的影响。结果表明:以n(NCO):n(OH)=10:1、DMP-30用量为2.5%的PUI配方为基础制备的PUI/MMT纳米复合材料的力学性能和热稳定性都得到显著提高,当Nano-MMT用量为3%时,复合材料的综合性能最优。     

聚丙烯/尼龙/纳米蒙脱土膨胀型阻燃材料的研究

用尼龙6(PA6)代替季戊四醇(PT)作为成炭剂组成的膨胀型阻燃聚丙烯(PP)有熔滴、阻燃效果差的缺点，加入纳米蒙脱土(nano-MMT)作为阻燃剂的协效剂后可克服以上缺点。研究结果表明：加入质量分数为4％的nano-MMT不仅克服了阻燃体系熔滴的缺点，还使材料的拉伸强度提高了44．3％；热重分析和燃烧测试表明，nano-MMT的加入提高了材料的热稳定性，使剩炭率增加了12％，从而提高了材料的阻燃性能；由扫描电镜(SEM)观察发现：nano-MMT的加入增强了材料的界面粘结力，提高了材料的韧性，起到了一定的增容作用。     

偶联修饰纳米蒙脱土/超高分子量聚乙烯基复合材料的摩擦磨损性能

通过模压烧结法制备了超高分子量聚乙烯(ultra-high molecular weight polyethylene,UHMWPE)与硅烷(silane,s)和钛酸酯(titanate,t)偶联剂修饰的纳米蒙脱土(nano-montmorillonite,nano-MMT)复合材料,nano-MMT含量由0到15%(质量分数,下同).采用45#钢为摩擦对偶件的往复滑动式摩擦磨损试验机,在室温干摩擦条件下测试了复合材料的摩擦学性能,实验条件为:接触压力P=8.0 kN、滑动速度v=1.8 m/min、时间t=3 h;用扫描电镜观察了复合材料磨损表面的形貌并分析了磨损机理.结果表明:随nano-MMT含量的增加,偶联修饰的nano-MMT/UHMWPE复合材料的硬度、摩擦系数和磨损率增加;偶联修饰改善了复合材料的摩擦学性能;与钛酸酯相比,硅烷偶联修饰nano-MMT/UHMWPE复合材料的硬度和摩擦学性能更好.用5%硅烷偶联修饰的nano-MMT,5%钛酸酯偶联剂修饰的nano-MMT和5%nano-MMT增强的UHMMPE复合材料的摩擦系数μ、摩擦温度θ、磨损率W分别为:μs=0.124,μt=0.135,μ=0.180;θs=92℃,θt=96 ℃,θ=94 ℃;Ws=4.25×10-7 mm3/(N·m),Wt=6.31×10-7 mm3/(N·m),W=18.80×10-7 mm3/(N·m);两种偶联修饰复合材料的表面磨损情况相似,含5%nano-MMT的复合材料主要表现为粘着磨损,而含15%nano-MMT的复合材料主要表现为表层和亚表层的脆性疲劳断裂.     

硅丙乳液与聚氨酯乳液的复合改性

以甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、丙烯酸羟丙酯、丙烯酸、乙烯基硅油为原料,采用种子乳液聚合法合成了硅丙乳液;以甲苯二异氰酸酯、聚醚二元醇、二羟甲基丙酸(DMPA)为原料,合成了聚氨酯乳液。并用聚氨酯乳液与硅丙乳液进行复配改性。研究了乙烯基硅油用量对硅丙乳液性能及复合乳胶膜性能的影响、DMPA用量及n(—NCO)∶n(—OH)值对聚氨酯乳液性能的影响、聚氨酯用量对复合乳胶膜的拉伸强度、断裂伸长率、粘接强度的影响。结果表明,制备硅丙酯乳液的较佳配比是乙烯基硅油的质量分数8%,m(BA)∶m(MMA)=3∶2;制备聚氨酯乳液的较佳配比为n(—NCO)∶n(—OH)=1.15~1.3,DMPA的质量分数为6%;聚氨酯乳液的质量分数为20%时,复合乳胶膜的粘接强度、拉伸强度和扯断伸长率分别提高86.7%、32.8%和24.9%。     

生态合成革用高固含量水性聚氨酯乳液的合成

以异氟尔酮二异氰酸酯、六亚甲基二异氰酸酯、聚四氢呋喃二醇、聚己内酯二醇等为主要原料,以2,2-二羟甲基丁酸(DMBA)和N-60胺基磺酸盐作为亲水性扩链剂,合成了一系列高固含量水性聚氨酯乳液。分别考察了n(—NCO):n(—OH)、软段组成、扩链剂种类及用量对乳液固含量及性能的影响。结果表明:n(—NCO):n(—OH)为1.3:1.0,软段聚醚与聚酯的摩尔比为1:2,DMBA质量分数为1.5%,N-60胺基磺酸盐质量分数为0.2%时,合成的水性聚氨酯乳液固含量高、黏度低、稳定性好、综合性能优异,适合制备生态合成革。     

纳米二氧化硅/聚氨酯酰亚胺复合泡沫材料的制备与性能

采用预分散法和一步法制备了纳米SiO2/聚氨酯酰亚胺(PUI)复合泡沫材料,考察了纳米SiO2对PUI发泡过程的影响,研究了纳米SiO2/PUI复合泡沫材料的泡孔结构及性能。结果表明,在PUI发泡过程中,随着纳米SiO2用量的增加,复合泡沫材料的开孔率增大,可有效防止泡沫收缩,且密度也减小;当纳米SiO2用量为10份时,纳米SiO2/PUI复合泡沫材料具有比较均匀的泡孔结构,且具有较高的开孔率、良好的阻燃性和热稳定性;柔软性泡沫还具有较好的吸声性能     

Preparation and characterization of liquid crystalline polyurethane‐imide modified epoxy resin composites

Liquid crystalline polyurethane‐imide (PUI) was synthesized from polyethyleneglycol, toluene diisocyarate, and pyromellitic dianhydride by solution polymerization and characterized by FTIR spectrum. The liquid crystal properties of PUI were verified by differential scanning calorimetry, polarizing microscope (POM), and X‐ray diffraction. PUI is a longitudinal liquid crystal with LC sequences in the backbone along the main‐chain direction. PUI was used to blend with epoxy resin(ER) as a modifier. The mechanical properties, thermal property, and morphology of PUI/ER composites were investigated. It was found that PUI was a kind of thermotropic liquid crystal material within a wide range of temperature. Remarkable improvement in strength and toughness of ER/PUI composites was achieved by the blending of PUI with epoxy in appropriate proportions. The maximum for bending strain and bending strength of the composite reached the level of 10.65% and 178 MPa, respectively when the mass fraction of PUI was 15 wt%. The mechanical behaviors of the PUI/ER were consistent with morphology analysis of the fracture surfaces of PUI/ER composites from SEM. POLYM. ENG. SCI., 54:1704–1711, 2014. © 2013 Society of Plastics Engineers     

酚醛树脂改性纳米蒙脱土填充PA6的制备及性能研究

分别利用经十八烷基三甲基氯化铵(OTAC)、酚醛树脂(PF)表面改性的纳米蒙脱土(MMT)填充聚酰胺(PA)6,研究了不同表面改性剂及其用量对PA6的力学性能、热性能和吸水性的影响。结果表明,经OTAC改性的纳米MMT和经PF改性的纳米MMT对PA6的热性能改善效果有限,但有利于提高PA6的刚性和降低吸水性。PF改性纳米MMT对PA6的改性效果优于OTAC改性纳米MMT,当PF改性纳米MMT的质量分数为3%时,材料的拉伸强度、弯曲强度和维卡软化温度分别比纯PA6提高了12.3%、58.8%和2%,吸水率降低0.5%。     

Investigation on suitability of poly(urethaneimides) as biomaterials

The mechanical properties of poly(urethaneimides) (PUI) were compared with known biomedical polyurethanes. The resistance of PUI to extraction with hexane and water and to sterilization with ethylene oxide or water vapor was stated. Water sorption and the permeability of water vapor, oxygen, and carbon dioxide through PUI foils were investigated. In blood compatibility, the PUI foils were similar to cellulose material Cuprophane, used in dialysis. Preliminary in vivo testing of PUI implanted in rats indicated good biocompatibility of this polymer. © 1995 John Wiley & Sons, Inc.     

木材用玉米淀粉胶粘剂的改性研究

以玉米淀粉为原料、次氯酸钠为淀粉的氧化剂和过硫酸铵(APS)为聚乙烯醇(PVA)的氧化剂,在碱性条件下将氧化玉米淀粉与氧化PVA进行接枝改性,制备出-种木材用胶粘剂。考察了PVA浓度、纳米蒙脱土(MMT)含量和固含量等对淀粉胶粘剂干、湿态胶接强度的影响。结果表明:当固含量为28.57%、u(PVA)=5%和w(纳米MMT)=2%时,相应淀粉胶粘剂的综合性能相对最好。     

纳米蒙脱土复合填充PP的增韧增强研究

通过直接熔融插层法制得聚丙烯纳米蒙脱土复合材料，测量了复合材料的力学性能及熔体流动速率。通过扫描电镜(SEM)照片分析了复合材料的相态结构；通过偏光显微镜(PLM)对不同蒙脱土添加量的复合材料的结晶结构进行了分析。结果表明，添加蒙脱土能提高聚丙烯的拉伸性能和冲击性能．且当添加量为3％(质量分数)时，力学性能最好。     

Preparation and characterization of epoxy resin modified with alkoxysilane‐ functionalized poly(urethane‐imide) by the sol–gel process

The sol–gel process has been frequently employed for preparation of high performance silica/polymer composites. In this paper, novel sol–gel precursor triethoxysilane‐terminated poly(urethane‐imide) (PUI‐Si), combining the advantages of polyurethane (PU) and polyimide, was synthesized and characterized. Then PUI‐Si was incorporated into the epoxy resin matrix to prepare a series of EP/PUI‐Si organic‐inorganic hybrids through an in situ sol–gel process and crosslinking reactions. The thermal stability of EP/PUI‐Si hybrids was evaluated by thermogravimetric analysis and the results show that the PUI‐Si could significantly improve the thermal properties of epoxy resin. The initial decomposition temperature of composites with 50 wt% PUI‐Si reached 347.1 °C, 157.3 °C higher than that of neat epoxy resin. Furthermore, the tensile strength and breaking elongation can also be clearly improved by adding a suitable amount of PUI‐Si. Similarly, the water contact angle increased to 97.4° with 70 wt% PUI‐Si, showing a hydrophobic surface. The morphology was investigated by transmission electron microscopy and the results reveal that the silica particles are smaller than 20 nm and have a strong interaction with the epoxy resin matrix, resulting in the above‐mentioned high performance properties. Copyright © 2011 Society of Chemical Industry     

退役汽车保险杠的同级回收利用

针对退役汽车保险杠塑料回收利用问题,提出了塑料喷丸表面除漆与回收料改性再生的技术方法。通过有限元仿真和实际除漆实验研究了保险杠表面塑料喷丸除漆的过程,仿真与实际实验结果说明了在80 m/s的垂直喷丸速度下,可以有效去除保险杠表面油漆,并且基体材料不受到破坏。在保险杠除漆回收料中添加聚丙烯(PP)新料、纳米蒙脱土(nano-MMT)、PP接枝马来酸酐(PP-g-MAH),通过双螺杆挤出机制备改性保险杠回收料,并测试了其拉伸与弯曲性能、缺口冲击强度、洛氏硬度和熔体流动速率,发现在除漆回收料/PP新料/nano-MMT/PP-g-MAH质量比为7/3/1/1的改性再生配方下,改性回收料的各项性能基本达到同级利用的标准要求,退役汽车保险杠材料的价值利用梯度得到提高。     

Improved mechanical,thermal, and flame-resistant properties of polyurethane–imide foams via expandable graphite modification

Although polyurethane–imide (PUI) foams combine the advantages of both polyurethane foam and polyimide foam, the performance of PUI might still not reach certain high-level requirements. Thus, expandable graphite (EG), as a kind of effective reinforcing filler, was introduced into the PUI matrix to improve the physical properties of the foam. Furthermore, to enhance the interfacial compatibility, EG was surface-modified with a silane coupling agent. The experimental results show that the addition of EG was beneficial for enhancing the comprehensive performance of the PUI foams, especially their thermal stability and flame resistance. In particular, the surface-modified, EG-filled PUI foam exhibited outstanding enhancements compared to that with only pristine EG incorporation; not only the compressive strength but also the thermal degradation properties were greatly enhanced by the increased interfacial compatibility between PUI and EG. In addition, the flame-resistant properties were improved by the surface modification of EG. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 46990.