无机纳米填料/PE复合体系对PP耐候性能的影响

将无机纳米材料、线性低密度聚乙烯(LLDPE)、高密度聚乙烯(HDPE)与聚丙烯(PP)熔融共混制备PP/LLDPE/HDPE/无机纳米耐候性复合材料。采用透射电子显微镜(TEM)、红外光谱仪(IR)、紫外-可见光谱仪(UW-V)以及力学性能测试等手段研究了聚乙烯(PE)/nano-SiO_2、PE/nano-TiO_2、PE/nano-ZnO复合体系对PP低温脆性和抗紫外老化性的影响。结果表明,复合材料中,无机纳米材料的质量分数为l%时,分散性最好,可促使PP与PE之间相互作用增强。PP/LLDPE/HDPE/nano-SiO_2低温抗冲击性能最好,温度为-10℃时其冲击强度保持率由纯PP的20.2%提高到了59.3%;PP/LLDPE/HDPE/nano-TiO_2的抗紫外线老化性能最好,老化144 h后断裂伸长率和冲击强度保持率分别提高到了43.9%和48.0%。     

PS/PP/Nano-TiO_2复合材料的制备及性能研究

采用熔融共混法制备了聚苯乙烯/聚丙烯/纳米二氧化钛(PS/PP/nano-TiO2)复合材料,并对该复合材料的力学性能、热稳定性和微观结构进行了研究。结果表明:随着nano-TiO2用量的增加,PS/PP/nano-TiO2复合材料的亲水性和热稳定性明显提高,冲击和拉伸强度均先增大后减小,其中当nano-TiO2用量为2%时,复合材料的力学性能均达到峰值;此外微观分析结果显示,nano-TiO2的引入改善了PS与PP的相容性。     

纳米TiO_2表面接枝PAN及其对PP抗紫外老化性能的影响

采用细微乳液聚合法制备了基于共价键结合的纳米TiO2表面接枝聚丙烯腈(PAN)(纳米TiO2-g-PAN)复合抗紫外老化剂,将其与聚丙烯(PP)共混制备了PP/纳米TiO2-g-PAN复合材料。研究了纳米TiO2-g-PAN在PP中的分散情况及PP/纳米TiO2-g-PAN复合材料的抗紫外老化性能。傅立叶变换红外光谱、热失重、扫描电子显微镜和力学性能测试分析表明,PAN成功接枝到纳米TiO2表面,提高了纳米TiO2与PP的相容性及PP/纳米TiO2-gPAN复合材料的热稳定性能、力学性能和抗紫外老化性能。当纳米TiO2-g-PAN与PP配比为0.05时,PP/TiO2-gPAN复合材料的拉伸强度、冲击强度、拉伸强度保持率和冲击强度保持率分别为38.66 MPa,691.75 kJ/m2,63.49%和58.42%,综合力学性能最佳。     

纳米材料改善聚丙烯抗紫外性能的研究

以纳米TiO2、SiO2为添加剂，利用它们能吸收、反射紫外线的特性，使之与聚丙烯（PP）共混，赋予PP抗紫外线性能。延长了PP的使用寿命。通过力学性能、熔体流动速度测定和外光谱及差示扫描量热分析（DSC）等手段，对加入纳米材料的PP试样进行了分析，研究了PP的抗紫外性能。     

无机纳米粒子改性PP热氧老化性能的研究

采用热烘箱老化法,研究了无机纳米粒子对聚丙烯(PP)热氧老化性能的影响;并对PP老化前后的羰基含量和力学性能的变化进行了表征,同时也表征了纯PP及改性PP的热氧降解性能。结果表明,无机纳米粒子不同程度地抑制了PP的热氧降解反应,其中以TiO2的改性效果为最佳。     

纳米无机刚性粒子改性聚丙烯研究进展

综述了纳米CaCO3、纳米TiO2、纳米SiO2对聚丙烯（PP）的改性研究进展。重点讨论了纳米无机粒子对PP改性的机理和影响因素。结果表明，纳米粒子可改善PP的力学性能（增强、增韧）、抗老化性能及抗菌性能等。     

无机纳米填料改性聚丙烯的研究进展

综述了聚丙烯/无机纳米复合材料的制备、填料表面处理、物理力学性能。可用大分子相容剂或官能化聚丙烯,改善PP纳米材料的分散性、界面黏结和力学性能。研究表明:少量无机纳米粒子可增强增韧PP。     

ABS改性及其耐候性能研究

把TiO2、ZnO纳米粒子和有机抗氧剂加入到ABS中,制备其改性材料,进行紫外光老化和热氧老化试验,测定了老化前后ABS改性材料的力学性能。结果表明,ABS/TiO2(25nm)比ABS/TiO2(60nm)复合体系的抗紫外老化性能好;ZnO/TiO2/ABS复合体系有较好的抗紫外老化性能,但韧性有所下降;无机纳米粒子和有机抗氧剂配合使用时,ABS的抗热氧老化性能提高,说明两者有协同作用。     

含无机纳米粒子聚乙烯薄膜在高原地区应用的抗老化特性（2）

以几种无机纳米粒子和光稳定剂体系与低密度聚乙烯（PE—LD）通过熔融挤出制备了PE—LD复合薄膜。采用红外光谱分析、氙灯人工气候老化试验箱、万能材料试验机等进行与老化特征有关的羰基指数、力学性能等进行较全面的对比测试。研究结果表明：含ZnO无机纳米粒子对高原紫外线的反射屏蔽作用很显著；无机纳米粒子＋光稳定剂在抗光氧化降解能力方面有协同效应；SiO2、ZnO无机纳米粒子在高原抗紫外光老化的同时，对力学性能的改善很显著。     

PP/黏土纳米复合材料的结构与性能

采用熔体插层法制备聚丙烯（PP）/有机黏土（OMMT）纳米复合材料。XRD和TEM的测试结果表明,采用熔体插层法制备的PP/OMMT复合材料是剥离型纳米复合材料。力学性能实验结果表明,相容剂的加入提高了PP与OMMT之间的相互作用,使其各项力学性能都得到了提高;PP/OMMT纳米复合材料的各项力学性能在有机黏土含量较小的情况下,就可以有较大幅度的提高;与纯PP相比,相容剂含量为10 phr、有机黏土用量为1 phr的聚丙烯基纳米复合材料具有最好的各项力学性能。     

炭黑对动态硫化POE/PP热塑性弹性体性能的影响

采用动态硫化法制备POE/PP共混物,研究了过氧化二异丙苯（DCP）对POE/PP体系熔体流动速率（MFR）和力学性能的影响。交联助剂硫磺（S）的加入有效地提高了交联效果,当m（DCP）/m（S）=2/0.2时,体系的综合力学性能最佳。通过不同加工工艺制备POE/PP/炭黑共混物,并研究了炭黑用量对体系力学性能和老化性能的影响。结果表明,母料法制备的共混物更有利于炭黑的分散,体系性能更好,炭黑的加入使体系的耐热老化性和抗紫外性能明显改善。     

绢云母质无机紫外屏蔽剂在聚丙烯中的应用

用自制的绢云母质无机紫外屏蔽剂改性聚丙烯(PP),对光老化后的PP复合材料进行力学性能测试。结果表明:绢云母质无机紫外屏蔽剂可以显著改善PP复合材料的耐光老化性,同时提高复合材料的综合力学性能;其最佳添加量是20%。     

PP及PP/EPDM共混物室内外老化行为的研究

通过中国西部3个地区（新疆尉犁、西藏拉萨和四川成都）室外自然老化和室内加速老化（热氧、紫外老化）的对比,研究了聚丙烯及聚丙烯/三元乙丙橡胶（PP/EPDM）共混物室内外老化前后力学性能的变化和表面微观形态的变化,以及其室内外老化的对应关系。结果表明,室外老化初期PP的拉伸强度提高,老化中后期随着降解程度加剧拉伸强度下降;EPDM的加入提高了PP的耐老化性能,其中成都地区老化试样最为明显,24个月后拉伸强度保持率高达115 %;PP和PP/EPDM共混物室内热氧老化后拉伸强度变化不大,紫外老化后拉伸强度则呈现下降趋势;综合考虑热氧和紫外老化,通过时间等效关系可以更好地联系室内外老化,为预测材料在自然状态下的服役寿命奠定了基础。     

PP/无机纳米粒子/POE-g-MAH三元复合材料的研究

采用熔融共混法分别制备了PP/纳米SiO2/POE-g-MAH和PP/纳米TiO2/POE-g-MAH两种复合材料;通过力学性能测试和SEM照片研究了其力学性能及微观形态结构。结果表明:纳米SiO2和纳米TiO2对PP/POE-g-MAH复合材料具有增强增韧作用,在POE-g-MAH的用量为5%、纳米粒子的用量为2%时,PP/无机纳米粒子/POE-g-MAH复合材料的综合力学性能达到最佳;SEM分析表明,该复合材料在断裂过程中发生塑性变形,因而韧性较佳;由DSC分析可知,纳米SiO2、TiO2均对PP基体有异相成核作用,此作用随POE-g-MAH的加入得到进一步促进。     

The mechanism for inorganic fillers accelerating and inhibiting the UV irradiation aging behaviors of rigid poly(vinyl chloride)

The UV irradiation aging behaviors of PVC composites with several inorganic fillers were studied through Fourier transform spectroscopy (FTIR), ultraviolet spectroscopy (UV‐Vis), differential scanning calorimeter (DSC), scanning electron microscopy (SEM), and mechanical property test. It was found that incorporation of a small amount of the inorganic fillers such as CaCO₃, talc and SiO₂ could hold up the UV aging behaviors of PVC. Those filler‐filled PVC composites sheets after 20 days UV irradiation maintain lower carbonyl index (CI) and good appearance of surfaces, as compared with the corresponding neat PVC sheets, ascribed to high reflection of those fillers to UV light. While montmorillonite (MMT) and pyrophyllite fillers could accelerate the UV aging behaviors of PVC, which could be concluded from both the sharp increase of the CI and lower T_g due to the chain scission reactions because of their high absorbance of these fillers to UV light in 290–400 nm. In these two PVC composites, UV irradiation caused the deterioration of their mechanical properties and the appearance of rough, cracked and chalked surfaces after 20 days UV irradiation. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

自制光稳定剂HWPAN-g-TiO2与几种光稳定剂对聚丙烯性能的对比研究

利用废旧腈纶织物制备了一种聚丙烯（PP）用大分子紫外屏蔽吸收类型光稳定剂,利用其和通用的受阻酚类光稳定剂分别制备耐候性PP复合材料,并进行了人工加速老化实验。探究了大分子紫外屏蔽吸收类型光稳定剂在PP老化过程中对PP老化降解的影响,并与通用的受阻酚类光稳定剂进行了对比研究。结果表明,大分子紫外屏蔽吸收类型光稳定剂效果明显,在人工加速老化500 h之后,PP的羰基指数高达150.3;而PP/HWPAN-g-TiO2仅为53,与此同时,PP的拉伸强度从25 MPa降至6.9 MPa,下降了72.4 %;而PP/HWPAN-g-TiO2的拉伸强度从29 MPa降至25 MPa,下降13.8 %。     

Gloss and degradation of hydroxyl polyacrylic resin/hexamethylene‐1,6‐diisocyanate coatings under ultraviolet and natural‐exposure aging

Reactive coatings of hydroxyl polyacrylic resin (HPAR) with hexamethylene‐1,6‐diisocyanate were carried out under accelerated 313‐nm ultraviolet (UV) aging for 2000 h and under natural exposure in Lhasa, Tibet, for 24 months. With UV irradiation and exposure time, the gloss changes in coatings with HPAR containing 3.0% or less hydroxyl groups decreased exponentially, whereas the gloss decay of coatings with HPAR containing over 4.5% hydroxyl groups decreased linearly. During 254‐nm UV aging, the gloss changes in coatings with HPAR containing 1.4% or less hydroxyl groups decreased as a Gaussian function. The weather resistance of a coating was correlated to the HPAR, UV irradiation, temperature, and humidity. Scanning electron microscopy indicated that there were degradation reactions and that some substance was lost in the matrix polymer during accelerated UV aging; then, uneven surfaces appeared and caused decreased gloss. Accelerated UV aging was faster than natural‐exposure aging, and the aging velocity of 254‐nm UV was 3–5 times faster than that of 313‐nm UV. Through the changes in the gloss, the aging tolerance of a coating could be monitored, and its aging resistance could also be predicted. The dynamic mechanical thermal analysis results showed that the coatings had good properties. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1271–1278, 2007     

Improvement of Mechanical Properties of Jute Fibers-Polyethylene/Polypropylene Composites: Effect of Green Dye and UV Radiation

Jute-reinforced polyethylene (PE), polypropylene (PP) and mixture of PP/PE composites were prepared. It was found that 90% PP and 10% PE matrices based jute reinforced composites performed the better results. UV radiation at different intensities was applied both on matrices and jute. Mechanical properties of the irradiated jute- and matrices-based composites were found to increase significantly. Optimized jute fabrics were also treated with different concentrations of green dye (0.1–1%, w/w) with 2% K₂O₈S₂ in methanol solution for 2–8 min. A composite made of 0.5% green dye jute (5 min soaking time) and irradiated matrix showed the best mechanical properties.     

PMA表面接枝包覆纳米TiO2及其在PP中抗紫外老化的研究

以硅烷偶联剂对纳米TiO2进行表面预处理，在此基础上以聚甲基丙烯酸（PMA）对其表面接枝包覆，后以马来酸酐接枝聚丙烯（PP-g-MAH）为载体，通过母料复合工艺制备了PP纳米复合材料。分析了处理后纳米TiO2的结构并对其在PP中的分散情况及抗紫外老化性能进行了比较。结果表明：PMA在纳米TiO2表面接枝率约为50％；与未处理TiO2及硅烷处理样品相比，PMA接枝包覆使纳米TiO2在PP中的分散均匀性及抗紫外老化性能均获得了改进。