Compatibility and Properties of Biodegradable Blend Films with Gelatin and Poly（vinyl alcohol）

The blend films with gelatin and poly（vinyl alcohol） （PVA） were prepared by a solution casting method. The compatibility between gelatin and PVA in the blend films was investigated. The transmittance, Fourier-transform infrared spectroscopy （FTIR）, x-ray diffraction （XRD）, thermogravimetry analysis （TG）, and differential scanning calorimetry （DSC） were employed to characterize the resultant blend films. According to optic result, the opacity of the blend film at the ratio of 20/80 （w/w, Gel to PVA） was the lowest, indicating the best compatibility between Gel and PVA at the ratio. The results oflR, XRD, DSC, and TG revealed an intensive interaction and good compatibility between them in the blend film at the ratio. The mechanical properties and solubility showed that PVA content in the blend films obviously affected the elongation at break and solubility. The mechanical properties and water resistance of gelatin film may be improved by the introduetion of PVA.     

Properties and Structure of Magnesium Matrix Composite Reinforced with CNTs

By using high pure Magnesium (99.9 wt% ) as matrix and multi-walled bended carbon nanotubes ( CNTs ) as reinforced phase, carbon nanotubes/magnesium matrix composite was prepared to the foundry method under the argon gas protection, and its mechanical properties were tested. The interface structure and component of plating and un-plating carbon nanotubes were analyzed by TEM and EDS , and the action mechanism was discussed. The experiment results show that the CNTs con strengthen mechanical properties of the nano-tube-reinforced Mg matrix composite, the tensile strength and elongation ratio are greatly improved. Furthermore, the plating CNTs are better than un-plating CNTs in strengthening effects. The tensile strength is inereased by 150% and the elongation ratio is increased by 30% than that of matrix when content of CNTs is 0.67 wt%.     

PVA/PAA/BC复合水凝胶的制备与性能

利用冰冻-解冻循环法制备聚乙烯醇（PVA）/聚丙烯酸（PAA）/细菌纤维素（BC）复合水凝胶.研究BC与单体丙烯酸（AA）用量对PVA/PAA/BC复合水凝胶的力学性能和溶胀特性的影响,初步探讨PVA/PAA/BC复合水凝胶的pH敏感性.实验结果表明：随着BC添加量的增多,PVA/PAA/BC复合水凝胶的含水率和拉伸强度与PVA/PAA水凝胶相比均有一定程度的提高,SEM表明复合水凝胶的网络交联点增多;加入AA会使复合水凝胶拉伸强度减小,但溶胀性能提高很多.综合考虑,BC添加量为4%,AA添加量为8%时,各项性能均较好.     

淀粉基/聚乙烯醇复合薄膜的制备及性能研究

以淀粉和聚乙烯醇为主要原料,丙三醇为增塑剂,通过流延成膜法制备淀粉基/聚乙烯醇生物薄膜.考察了料液浓度、原料配比及增塑剂含量对复合薄膜力学性能、耐油性能以及结晶性能的影响.研究结果表明:复合薄膜的最佳料液浓度为7.5%;聚乙烯醇的含量越高,共混膜的综合性能越好;当淀粉、聚乙烯醇与增塑剂的质量比为6∶6∶4时,制备的淀粉基/聚乙烯醇复合薄膜的力学性能最好,其拉伸强度和断裂伸长率分别达到13.3MPa和160%;偏光显微镜测试结果表明其相应材料的结晶性能最佳.     

聚乙烯醇/纳米氧化锌复合材料的性能

为了改善聚乙烯醇的性能,通过熔融挤出的方法制备了聚乙烯醇/纳米氧化锌复合材料.采用力学性能测试、热分析、X射线衍射和紫外光谱研究了纳米氧化锌对聚乙烯醇力学性能、热稳定性、结晶性能和紫外屏蔽性能的影响.结果表明:复合材料的拉伸强度和断裂伸长率分别在纳米氧化锌含量为1.0wt%和0.5wt%时达到最大值,拉伸强度比纯聚乙烯醇提高了20.27%,断裂伸长率略高于纯聚乙烯醇;当纳米氧化锌含量为2.0wt%时,复合材料失重10%的温度比纯聚乙烯醇提高20℃;纳米氧化锌显著提高了聚乙烯醇的耐光老化性能,同时使聚乙烯醇中产生了新的晶相.纳米氧化锌的加入有助于多种性能的改善.     

PVA与超高摩尔质量PEO复合膜的制备及表征

将聚乙烯醇（PVA）与超高摩尔质量的聚氧化乙烯（PEO）进行共混,制备了PVA-PEO复合膜,并对混合溶液的流变行为、力学性能及其结晶行为进行了考察.研究发现：PVA水溶液及PVA-PEO混合溶液的稳态流变行为均呈现明显的第一牛顿区、非牛顿区和第二牛顿区.少量PEO的加入使混合溶液的黏度增大,但增加幅度不大|PEO加入后得到的PVA-PEO复合膜的弹性模量、断裂强度及断裂伸长率等力学性能及玻璃化温度均有所提高,且随着PEO质量分数的提高,各项力学性能均得到增强,这与在成膜过程中PEO的加入使PVA的晶区尺寸变小而分布均匀,以及体系中物理交联点增加有关.     

纳米纤维素晶须/壳聚糖天然可降解复合膜的制备与性能

以纳米纤维素晶须(NCW)为增强体、壳聚糖(CS)为基体,通过流延法制得天然可降解复合膜。通过电子显微镜(SEM)、红外光谱(FT-IR)、X射线衍射(XRD)等手段对复合膜进行结构表征,并对复合膜的动态力学性能、干湿态拉伸性能进行了测试。结果表明:NCW与CS具有很好的相容性;NCW的加入显著提高了CS膜的储能模量、拉伸模量和拉伸强度。NCW能够进一步拓宽CS材料的应用领域和价值。     

聚乳酸/醋酸淀粉薄膜的制备及性能研究

采用溶剂挥发成膜法分别制备了聚乳酸(PLA)/淀粉(DPS)和聚乳酸(PLA)/醋酸淀粉(AS)复合薄膜,并通过添加增塑剂改善复合薄膜的力学性能.对样品薄膜进行SEM、TG、DMA和机械性能测试,结果表明:PLA/AS复合薄膜与PLA/DPS复合薄膜相比,各组分的相容性以及薄膜的断裂伸长率得到了改善,尤其是增塑剂的添加使复合薄膜的力学性能得到了明显提高.     

丝素/水性聚氨酯膜的制备及表征

首次采用丝素粉体和水性聚氨酯按不同比例混合,经热压法成功制备出丝素/聚氨酯共混薄膜。红外光谱、X-射线衍射、动态力学分析及拉伸实验结果表明：聚氨酯的加入,促进了丝素蛋白分子β-折叠结构的形成,导致丝素结晶度提高;丝素含量越大,共混膜中聚氨酯的玻璃化温度越低,共混膜的拉伸断裂强度和初始模量越高;当丝素含量从0到70%变化时,试片的断裂强度由0.6MPa增大到10.4MPa,断裂伸长率从1065%下降到47.5%。聚氨酯的加入改善了共混膜的弹性,韧性随聚氨酯含量的增大而增大。     

玻璃纤维增强MC尼龙复合材料的力学性能

考察了玻璃纤维增强ＭＣ尼龙（ＧＦＲＭＣＮ）中玻璃纤维的表面处理及加入量对力学性能的影响。并用ＳＥＭ对ＧＦＲＭＣＮ材料界面及其对力学性能的影响进行了研究。结果表明：使用ＫＨ５５０作偶联剂对ＧＦＲＭＣＮ复合材料是很有效的。当玻纤加入４０％时,拉伸强度比基体提高３２．２％,拉伸弹性模量提高了１５２％,弯曲强度提高７４．３％,弯曲弹性模量提高了１１７％,而缺口冲击韧性提高了１６２％。根据材料的制备工艺特点     

Fabrication and Characterization of Nano- CaCO3/Polypropylene Foam Sheets

By applying the reinforcing and toughening effect of calcium carbonate （CaCO3） nanoparticles on polypropylene, foam sheets of good performance were successfully fabricated by extrusion. The equipment and conditions of the extrusion were explored. The mechanical properties of the produced foam sheets were tested. The effect of CaCO3 nano-particles on the mechanical properties and the cellular structure of the sheets was comprehensively studied. The experimental results show that the optimum content of CaCO3 nano-particles in the composite material was -4wt%. At this content, the nano-particles were well dispersed in the substrate, and the composite material had maximum tensile strength and impact strength. Surface treatment of the nano-particles only affected the impact strength of the composite material. CaCO3 micro-particles, on the other hand, showed little effect on the properties of the composite material when the micro-particles content was less than 5 wt%. At a content higher than 5wt%, the properties of the composite material significantly worsened.     

Mechanical Properties and Morphology of the Clay/Waterborne Polyurethane Nanocomposite

Stable clayl waterborne polyurethane nanocompostie dispersions were synthesized by sulfonated poly （ butylene adipate ） diol , 4,4-diphenylmethane diisocyanate , dimethyl propionic acid, 1,4-butanediol, triethyl amine and clay-water dispersion through a route named prepolymer acetone mixing progress. The reinforced mechanical properties and thermal resistance of films casting from h were examined by dynamic mechanical analyses （ DMA ）, thermogravimetrie analyses （ TGA ） and tensile tests. Furthermore, the morphology of these nanocompostie films and dispersions were observed by transmission electron microscopy（TEM）, scanning electron microscopy（SEM）, wide-angle X-ray diffraction analyses（ WXRD ）. The experimental results reveal that the clay could be predominantly dispersed in the pristine polymer forming nanacomposties, and evidently enhanced the tensile properties and modulus of it. Addhionally, the best-reinforced effect could occur when the clay content was near 1 wt% .     

PVA纤维增强水泥基复合材料的性能试验研究

通过单轴抗压试验、直接拉伸试验、四点弯曲试验、抗折试验对不同配比和不同试件形状的PVA纤维增强水泥基复合材料进行力学性能试验研究,结果表明：加有PVA纤维的水泥基复合材料的抗压强度提高不大,大约是10%,而抗拉强度和抗弯强度则提高很多,且出现了许多细小裂缝,呈现出应变硬化特性,极限拉应变可达1.8%;利用直板型试件做直接拉伸试验比胫型试件做直接拉伸试验的试验结果准确,且易于试验操作.试验结果证实了PVA纤维增强水泥基复合材料具有很好的韧性.     

PVC/SBS共混材料力学性能研究

以通用型PVC树脂为基体,使用SBS-g-MAH通过双螺杆挤出机对其进行共混改性,研究了SBS-g-MAH的含量对PVC/SBS-g-MAH共混材料的力学性能影响.结果表明,SBS-g-MAH的引入可以提高PVC树脂的断裂伸长率、冲击强度,而材料的拉伸强度则降低.当SBS-g-MAH含量为5%时,断裂伸长率出现极大值;SBS-g-MAH含量为20%时,冲击强度出现极大值.     

湿法共混制备聚丁二酸丁二醇酯/淀粉食品包装膜

以水和甘油为增塑剂,将玉米淀粉与聚丁二酸丁二醇酯（PBS）直接湿法共混得到母粒,进而流延制备了PBS/淀粉薄膜.扫描电镜（SEM）观察发现,用甘油/水混合增塑的淀粉可以在PBS基体中均匀的分散,与淀粉干法填充改性相比,原位塑化后的淀粉与PBS的相容性得到明显改善,并且薄膜的综合力学性能较好.甘油∶水为1∶2,增塑剂用量为淀粉的15%时,薄膜的横纵向拉伸强度在淀粉含量为11.5%时最高,此时横纵向断裂伸长率分别较纯PBS薄膜提高了147.2%和51.3%,横纵向直角撕裂强度分别提高了160.8%和57.3%.随淀粉填充量的不断增加,薄膜的横纵向拉伸强度和直角撕裂强度都有所下降,但横纵向断裂伸长率却在淀粉填充量为30%时最高.在淀粉填充量高达25%和30%时,薄膜横纵向拉伸强度仍分别可以满足GB/T 4456—1996＂包装用聚乙烯吹塑薄膜＂中规定的A类优等品和合格品的要求.该薄膜材料在满足食品等包装使用需求的同时,有效地降低了成本,并且可以完全生物降解.     

星型木质素衍生物增强大豆蛋白塑料

星型羟丙基木质素（HL）填充大豆蛋白（SPI），得到具有良好力学性能的可生物降解SPI／HL复合材料（SL）。复合材料的结构和性能被XRD、DSC、sFM、TEM和拉力测试表征。结果表明：仅仅加入质量分数2％的HL就在大豆蛋白塑料伸长率基本不变下，使拉伸强度达到16．8MPa，提高了2．3倍。随札含量的增加，HL诱导形成纳米尺度的超分子特征的微区。虽然超分子微区使强度得到进一步提高，但却导致甘油在SPI基质中缺失，材料变脆、综合性能下降。当儿以单分子形式存在于复合材料中时，伸展的支链能够将SPI中的杂微区相互联系在一起，得到最优力学性能的复合材料。     

Biodegradation and mechanical property of polylactic acid/thermoplastic starch blends with poly (ethylene glycol)

The effects of adding poly (ethylene glycol) (PEG) into polylactic acid/thermoplastic starch blends (PLA/TPS) on the properties were investigated by DSC, SEM and mechanical property-testing. The blends of PLA/TPS blended with increasing content PEG exhibited lower temperature of glass transition (Tg) and lower temperature of melting (Tm) as well as higher melt flow index (MFI), which indicates the plasticization and processability of the composites were dramatically improved. The tensile strength, flexural strength and izod impact strength of PLA/TPS (80/20) increased at first and then decreased with increasing content of PEG due to stronger interfacial adhesion. The optimized mechanical property can be obtained for the blend with 3 wt% PEG. The samples containing PEG after soil burial for 5 months showed quicker degradation being accompanied with large weight loss and mechanical properties loss.     

Preparation and mechanical properties of β-SiC nanoparticle reinforced aluminum matrix composite by a multi-step powder metallurgy process

β-SiC nanoparticle reinforced A1 matrix （nano-SiCp/A1） composite was prepared by a multi- step powder metallurgy strategy including presureless sintering, hot compacting process and hot extrusion. The microstructures of the as-prepared composites were observed by scanning electronic microscopy （SEM）, and the mechanical properties were characterized by tensile strength measurement and Brinell hardness test. The experimental results revealed that the tensile strength of the composite with the addition of 5wt%/3-SIC nanoprtieles could be increased to 215 MPa, increasing by 110% compared with pure A1 matrix. Comparative experiments reflected that theβ-SIC nanoprticles showed significant reinforcement effect than traditional a-SiC micro-sized particles. The preparation process and sintering procedure were investigated to develop a cost effective preparation strategy to fabricate nano-SiCp/A1 composite.     

碳纳米管增强铝基复合材料制备及性能研究

采用真空热压烧结法制备碳纳米管与 SiO2多相增强铝基复合材料,测量复合材料的体积密度,根据其理论密度计算其致密度;再对制得的复合材料进行硬度、抗压强度、抗剪强度等力学性能测试,并观察样品的剪切断口微观形貌,研究 CNTs 对复合材料力学性能的影响。低含量的碳纳米管由于其在铝基体中的分散性及弥散度较好,作为第二相增强相,所制备的铝基复合材料的致密度、硬度、抗压强度与剪切强度均优于高含量碳纳米管增强铝基复合材料。 CNTs 的含量、以及其在铝基体中的弥散度是影响铝基复合材料力学性能的关键因素。     

Effect of Hyperbranched Poly(amine-ester) Grafted Nano-SiO2 on Reinforcement and Toughness of PVC

Nano-SiO2 was modified using silane coupling agent(KH-550) and hyperbranched poly(amine-ester) respectively,and Poly(vinyl chloride)(PVC)/modified nano-SiO2 composites were made by melt-blending.The composites' structures andmechanical properties were characterized by transmission electron microscopy(TEM),sanning electronic microscopy(SEM) and electronic universal testing machine.The results show that nano-SiO2 grafted by hyperbranched poly(amine-ester) increases obviously in dispersion in PVC matrix,and mechanical properties of PVC are effectively improved.Moreover,it was found that mechanical properties of PVC/nano-SiO2 composites reach the best when weight percent of nano-SiO2 in PVC matrix is 1%.Compared with crude PVC,the tensile strength of hyperbranched poly(amine-ester) grafted nano-SiO2/PVC composite increases by 24.68% and its break elongation,flexural strength and impact strength increase by 15.73%,4.07% and 1 841.84%,respectively.Moreover,the processing of the composites is improved.