高强度抗老化土工布的制备与性能表征

为提高土工合成材料在实际工程应用中的耐久性和安全性,制备了一种抗老化聚丙烯/高模高强聚乙烯醇短纤维混合土工布,讨论了聚乙烯醇纤维含量对土工布力学和反滤性能的影响,采用扫描电子显微镜观察其内部微观结构,通过相关测试表征了其耐候性以及耐金属离子性能。结果表明：聚乙烯醇纤维均匀分散在土工布内部,使得纤维间缠结更加紧密;高模高强聚乙烯醇纤维含量为60% 时,土工布的力学和反滤性能均得到显著提高,干、湿态断裂强度分别为29.7、34.8 kN/m;等效孔径为0.109 3 mm;同时,耐候性及耐金属离子性能均得到提高,经过90 d光氧老化和18 d热氧老化（硝酸铜溶液浸泡后）实验后,强度保持率分别为73.7%和64.3%。     

PP/PET针刺过滤材料热老化性能研究

为探索聚丙烯(PP)/聚酯(PET)针刺过滤材料的耐热老化性能,采用烘箱法对试验制备的3种PP/PET针刺过滤材料样品进行不同热老化温度和热老化时间的处理,研究热老化温度和热老化时间对PP/PET针刺过滤材料各项性能的影响。结果表明:随着热老化时间的延长和热老化温度的升高,PP/PET针刺过滤材料的质量、厚度、断裂强度降低,尺寸缩小;当热老化温度超过120℃、热老化时间超过4.0 h后,热老化程度明显加剧。     

高强粗旦聚丙烯纺黏针刺非织造土工布的耐久性研究

采用耐酸碱、室外自然老化、抗热氧老化和抗冻融试验,研究高强粗旦聚丙烯纺黏针刺非织造土工布的耐久性,并将其与聚酯纺黏针刺土工布、抗紫外线(UV)高强粗旦聚丙烯纺黏针刺非织造土工布进行对比.结果 表明:同等面密度条件下,高强粗旦聚丙烯纺黏针刺土工布比聚酯纺黏针刺土工布具有更优的耐酸碱性能、抗冻融性能及抗热氧老化性能,但耐光...     

改性聚芳噁二唑纤维的热氧老化性能

 采用热氧老化方法,研究了改性聚芳噁二唑纤维在200℃、250℃和300℃下的热氧老化趋势,并同间位芳纶和聚酰亚胺纤维进行了对比。结果表明：在200℃下经过80天的热氧老化,改性聚芳噁二唑纤维的断裂强度保留率接近90%,在250℃下经过65天的热氧老化,它的断裂强度保留率在60%以上,在300℃经过25天的热氧老化,其断裂强度保留率依然大于70%;同时对改性聚芳噁二唑纤维在高温热氧老化后的线密度测试表明,线密度没有明显变化,纤维在200℃、250℃和300℃下尺寸变化较小。     

聚丙烯长丝非织造土工布材料特性分析

对聚丙烯长丝非织造土工布的材料特性进行探究,测试其物理力学性能、耐久老化性能及耐酸、碱性能,结果表明:该材料具有良好的拉伸特性;耐久老化性能出众,其经500 h氙弧灯照射后,断裂强力保持率在90%以上,断裂伸长保持率在80%以上;具有较强的耐酸、碱性能,其能在质量分数为10%的酸、碱溶液中浸泡168 h后,断裂强度保持率和断裂伸长率保持率都在90%以上。     

PP抗光氧老化纺粘非织物布的开发及其性能

利用ZN-P型紫外线耐气候试验机加速PP抗光氧老化纺粘布的老化过程,通过拉伸仪测试其老化实验前后的断裂强度和断裂伸长率,根据其损失率来判断抗光氧老化剂的种类、添加量及色母粒对所制备的PP纺粘布抗光氧老化性能的影响。结果表明,经阻胺类抗光氧老化剂改性的PP纺粘布,其抗光氧老化性能明显优于紫外线类抗光氧老化剂改性的PP纺粘布,当其质量分数为2%～2.2%时性价比最好。同时,色母粒的加入对PP纺粘布的抗光氧老化性能也有较大的影响。     

PP抗光氧老化纺粘非织造布的开发及其性能

利用ZN-P型紫外线耐气候试验机加速PP抗光氧老化纺粘布的老化过程,通过拉伸仪测试其老化试验前后的断裂强度和断裂伸长率,根据其损失率来判断抗光氧老化剂的种类、添加量及色母粒对所制备的PP纺粘布抗光氧老化性能的影响.结果表明,经阻胺类抗光氧老化剂改性的PP纺粘布,其抗光氧老化性能明显优于紫外线类抗光氧老化剂改性的PP纺粘布,当其质量分数为2%～2.2%时性价比最好.同时,色母粒的加入对PP纺粘布的抗光氧老化性能也有较大的影响.     

TiO_2水溶胶改善聚丙烯土工布耐老化性的研究

探讨TiO_2水溶胶处理对聚丙烯土工布耐老化性能的改善效果。采用溶胶凝胶法制备TiO_2水溶胶,测试了经过TiO_2水溶胶处理后聚丙烯土工布不同老化时间下的耐酸性、耐碱性、耐水洗性和耐金属离子性。结果表明:TiO_2水溶胶在钛酸丁酯质量分数13%,冰醋酸质量分数25%,搅拌时间70min时,处理所得聚丙烯土工布防紫外线整理效果最好;经TiO_2水溶胶浸渍整理处理后的聚丙烯土工布防紫外性能得到提高,其耐酸碱性、耐水洗性、耐金属离子性较好。认为:TiO_2水溶胶处理能改善聚丙烯土工布的耐老化性能。     

聚丙烯纺黏针刺土工布的力学和耐光氧老化性能

为提高聚丙烯纺黏针刺土工布产品质量,测试和分析聚丙烯纺黏针刺土工布的力学性能和耐光氧老化性能.结果 表明:在相同工艺条件下,聚丙烯纺黏针刺土工布的力学性能优于聚酯纺黏针刺土工布;聚丙烯纺黏针刺土工布抗拉强度、撕破强力、顶破强力和刺破强力均随着面密度的增大而提高;灰色母粒和UV 88抗老化母粒均可提高聚丙烯纺黏针刺土工布...     

广适热合复合塑料制备及其性能研究

为找到一种同时能与PP、PE和PS热封的热合塑料,按照热封温度接近树脂熔融温度的原理,以线性低密度聚乙烯(LLDPE)、聚丙烯(PP)、聚苯乙烯(PS)、茂金属聚乙烯(mPE)四种熔融温度接近的树脂,按照不同比例共混流延制备薄膜,并测试膜的力学性能、光学性能、阻隔性能、热稳定性能、微观性能、抑菌性能以及防霉性能。当LLDPE/PP/PS/mPE比例为70:20:5:5时,薄膜的横、纵向拉伸强度分别为23.978、21.454 MPa,透过率为19.22%,雾度为66.577%以及其他性能均较好且结构紧密。并且在与PP、PE和PS热封时,表现出较强的热封性能,因此具有实际应用价值。     

紫外线辐射对聚丙烯非对称固液分离膜结构与性能的影响

对聚丙烯非对称固液分离膜进行紫外线辐射处理,得到不同温度下分离膜的老化规律,通过对分离膜的形态结构、物理机械性能和浸润性能进行研究,结果表明：在45 ℃处理1 d后,聚丙烯分离膜表面出现C=O伸缩振动峰,说明膜表面开始被氧化;在45 ℃和60 ℃分别处理6 d和4 d后,分离膜的断裂强度保持率分别为2.28%和5.81%,已失去使用价值,且膜表面的亲水性消失,导水性明显下降。     

Effect of Pasteurization, High-Pressure Processing, and Retorting on the Barrier Properties of Nylon 6, Nylon 6/Ethylene Vinyl Alcohol, and Nylon 6/Nanocomposites Films

ABSTRACT:  This study determined the impact of pasteurization, high-pressure processing (HPP), and retorting on the barrier properties of nylon 6 (N6), nylon 6/ethylene vinyl alcohol (N6/EVOH), and nylon 6/nanocomposite (N6/nano) materials. The pasteurized and high-pressure treated films were coextruded with low-density polyethylene (PE) as the heat-sealing layer. The retorted films were coextruded with polypropylene (PP). Oxygen transmission rate (OTR) and water vapor transmission rate (WVTR) of the samples were measured after pasteurization (75 °C for 30 min), HPP (800 MPa for 10 min at 70 °C), and retorting (121 °C for 30 min) treatments. These were compared with the thermal characteristics and morphologies of the samples using differential scanning calorimetry (DSC) and X-ray diffraction (XRD). Results showed that OTR of N6 and N6/Nano increased after HPP (16.9% and 39.7%), pasteurization (13.3% and 75.9%), and retorting (63.3% and 112.6%), respectively. For N6/EVOH, a decrease in OTR after HPP (53.9%) and pasteurization (44.5%) was observed. The HPP treatment increased the WVTR of N6 (21.0%), N6/EVOH (48.9%), and N6/Nano (21.2%). The WVTR of N6, N6/EVOH, and N6/Nano increased by 96.7%, 43.8%, and 40.7%, respectively, after pasteurization. The DSC analyses showed that the enthalpy and percent crystallinity increased (2.3% to 6.5%) in the N6/Nano when compared with the N6 material after each treatment. Retorting caused a decrease (3.5%) in the percent crystallinity of the polypropylene material. HPP did not cause major morphological changes to the samples. Results of the barrier studies were influenced by the crystallinity changes in the materials as seen in the XRD diffractograms.     

Effect of high‐pressure processing on the migration of antioxidant Irganox 1076 from polypropylene film into a food simulant

The effect of high‐pressure processing (HPP) on the migration behaviour of a typical antioxidant, Irganox 1076, from polypropylene (PP) flexible structures was studied. Initial concentrations of Irganox 1076 in polypropylene (PP) were 2.0 and 5.0 mg g^?1. The migration experiments were carried out on high‐pressure treated and non‐treated polypropylene pouches containing either 95 or 10% ethanol aqueous food simulating liquids (FSL) for 20 days at 40 and 60 °C. After the contact period, concentrations of Irganox in PP and FSL were measured to determine migration behaviour. The results showed that there was no significant difference in the concentration of Irganox 1076 migrating from PP, and into the FSL for pressure‐treated vs non‐treated samples. No significant concentration differences were found in non‐treated (control) samples and those treated for 5 and 10 min. However, there was a storage time effect on the migration level. There was also a significant migration effect on the migration of Irganox between the two different food simulants, and an increase in the HPP temperature increased the rate of migration. Copyright © 2004 Society of Chemical Industry     

丝织品的热老化及其寿命预测

为探究湿、热环境对丝织品文物保存状况的影响,在110、130 ℃条件下分别对桑蚕丝试样进行干热老化和湿热老化模拟实验。借助万能材料试验机、色度计、扫描电子显微镜和傅里叶红外光谱仪对老化前后试样的抗拉强度、颜色、微观形貌和结构进行了分析。同时,提出了丝织品的寿命预测方程。结果表明:试样强度随老化时间呈线性下降,颜色变黄;干热老化和湿热老化后,纤维表面出现不同程度的破坏,且湿热老化后,纤维束交织形成的孔洞周围较其他部位溶蚀显著;纤维二级结构中β-折叠构象含量显著降低,与强度变化趋势一致;低温、干燥条件适于丝织品文物的保存。     

双组分SMS非织造材料耐光老化性能研究

双组分SMS非织造材料和聚丙烯SMS非织造材料做直接大气曝露实验6个月,进行材料颜色、表面微观形态、强度、结晶度、红外光谱等项目测试,并对测试结果进行对比。研究表明,双组分SMS非织造材料耐光氧老化性能优于聚丙烯SMS非织造材料。     

织造工艺对聚丙烯土工机织物梯形撕裂强力的影响

本文通过正交试验的方法探讨织造工艺对聚丙烯土工机织物梯形撕裂强力的影响 ,并将实验所得数据进行方差分析 ,找出影响的原因 ,得出改善聚丙烯土工机织物梯形撕裂强力的织造工艺的调节方向     

Comparison between tensile and damage analysis of hybrid jute/polypropylene needlepunched nonwoven geotextiles produced from untreated and alkali treated jute fibers

The tensile properties of virgin and mechanically damaged samples are investigated for hybrid needlepunched nonwoven geotextiles consisting of untreated Jute/Polypropylene (PP) and alkali treated Jute/PP fibers in defined weight proportions. The damages in nonwovens were induced by two types of mechanical damages (circular hole and horizontal cut) in the center of hybrid nonwovens tested in the cross-machine direction. It was found that the horizontal cut was more detrimental than circular hole in nonwoven geotextiles consisting of jute (both untreated and alkali treated) and polypropylene fibers, specifically when the nonwovens were tested in the cross-machine (preferential) direction. Furthermore, Jute/PP hybrid nonwoven geotextiles were found to be notch-sensitive in nature. The ratio of damaged area of untreated and alkali treated Jute/PP nonwovens at the maximum level of tensile strain to that of the area of corresponding Jute/PP nonwoven determined in the beginning was found to be higher in untreated Jute/PP nonwovens. Similarly, Poisson’s ratio of untreated Jute/PP nonwovens was also found to be higher in comparison to alkali treated Jute/PP nonwoven geotextiles. The initial region of non-linearity of stress–strain curves matched well with that of volumetric deformation for both damaged nonwoven geotextiles. Accordingly, the initial region of stress–strain curves of damaged needlepunched nonwoven can be modeled as a linear region with constant volume deformation.