RGO/PHBH复合包装膜的制备及其抗静电性研究

目的 赋予聚羟基丁酸-羟基己酸酯(PHBH)包装膜优良的抗静电性能,使其在包装领域具有更广泛的应用.方法 通过抗坏血酸(Vc)还原氧化石墨烯(GO),制备还原氧化石墨烯(RGO)/PHBH包装膜,探讨包装膜的阻氧、防紫外及抗静电性能.结果 包装膜的氧气透过量最低可达到20 cm3/(cm2?d?Pa),紫外光透过率均小于40％,表面电阻由纯膜的29 GΩ大幅下降至0.25 MΩ.结论 与纯PBBH包装膜相比,RGO/PHBH复合包装膜的阻氧及抗紫外性能较高,并具有优良的抗静电性能.     

Mn-C共掺杂活性包装膜的研究

目的研究Mn-C复合材料对聚3-羟基丁酸酯-co-3-羟基己酸酯(PHBH)包装膜性能的影响,以期起到延长果蔬货架寿命的作用。方法通过溶液浇铸法制备Mn-C/PHBH活性包装膜,应用扫描电镜(SEM)、差式扫描量热法(DSC)、力学性能检测、透湿透氧透二氧化碳检测、气体分析仪和保鲜评价对活性包装膜的微观形貌、结晶性能、热稳定性、力学性能、阻隔性能和保鲜效果进行研究。结果当Mn-C复合材料的质量分数为5%时,Mn-C/PHBH的拉伸强度达到最大值,为24.38MPa,且制备的活性包装膜具有选择透过性,有利于形成低氧高二氧化碳的包装氛围,将具有乙烯脱除能力的活性包装膜用于果蔬储藏时能延长果蔬货架寿命。结论获得了Mn-C/PHBH活性包装膜综合性能最优时,Mn-C复合材料的最佳掺杂比例参数。     

ATBC含量对PLA/PCL复合包装膜性能的影响

目的研究增容剂含量对PLA/PCL复合包装膜性能的影响。方法将不同含量的乙酰柠檬酸三丁脂(ATBC)加入到PLA和PCL树脂中,并搅拌均匀,而后熔融挤出,先造粒后吹膜制得ATBC/PLA/PCL共混膜。对制得的包装膜进行扫描电镜分析,观察其微观断面,并进行力学性能测试,以获得其断裂伸长率和拉伸强度,采用DSC测试分析其熔融结晶行为,并进行氧气透过性测试,以获得其阻隔性能。结果 ATBC对改善PLA与PCL的相容性具有积极作用,显著提高了复合膜的断裂伸长率,从6%提高到250%;随着ATBC含量的增加,复合膜的氧气透过性能先增大后降低,并对复合膜的玻璃化转变温度和熔融温度有影响。结论当ATBC的质量占树脂总质量的8%时,共混膜具有最佳的性能。     

纳米蒙脱土负载茶多酚改性聚乙烯醇膜的制备及性能表征

目的 利用负载有茶多酚（TP）的蒙脱土（MMT）对聚乙烯醇（PVA）改性制备出PVA复合膜,以期改善纯PVA膜的综合性能,从而替代传统包装膜。方法 利用溶液流延法制备不同茶多酚（TP）质量分数的PVA/MMT复合膜（MMT添加量为PVA质量的3.0%）,测试其耐水性能、力学性能、水蒸气阻隔性能及抗氧化性能等。结果 当茶多酚质量分数为3.0%时,其溶胀率、溶解质量损失率分别约为532%和12.3%,水蒸气透过率系数约为1.0×10?10 g?m/(m2?Pa?s);抗张强度相对于PVA/MMT复合膜增强了约26%,断裂伸长率下降明显;PVA/MMT/TP复合膜的DPPH自由基清除率达到了65.5%。结论 采用蒙脱土负载茶多酚可有效改性PVA基复合膜。     

高强度高气体阻隔性羧甲基纤维素钠/蒙脱土复合材料制备及性能研究

将蒙脱土(MMT)填充到羧甲基纤维素钠(CMC)中制得CMC/MMT复合膜,研究MMT用量对CMC/MMT复合膜的力学性能和气体阻隔性能的影响,用扫描电镜和透射电镜进行结构分析。结果表明,添加适量的MMT可以显著提高CMC/MMT复合膜的力学性能和气体阻隔性能。当MMT添加量为10%(wt,质量分数)时,CMC/MMT复合膜的拉伸强度由105MPa提高到375MPa,水蒸汽透过系数为2.079×10~(-6)g·cm/m~2·s·Pa,透氧系数为1.65×10~(-15)cm~3·cm/cm~2·s·Pa。此外,由于MMT具有耐火性,CMC/MMT复合膜具有良好的阻燃性。     

壳聚糖/PHBH复合生物降解膜的性能研究

目的研究壳聚糖(CS)与聚3-羟基丁酸酯/3-羟基己酸酯(PHBH)复合成膜后的各项性能。方法以冰乙酸为共溶剂,将CS与PHBH采用共混流延法制备成CS/PHBH生物降解复合膜。利用红外光谱仪、扫描电镜及差热分析仪等研究不同质量比CS/PHBH对复合膜力学性能、结构、热稳定性,以及生物降解性能的影响。结果壳聚糖和PHBH之间存在分子间氢键,两者间产生了一定的相互作用,同时,CS/PHBH复合膜显示出较好的热稳定性和生物可降解性。当CS和PHBH质量比为3∶1时,CS/PHBH生物降解复合膜的拉伸强度与断裂伸长率优于其他质量比的复合膜。结论当CS和PHBH质量比为3∶1时,可得到综合性能优良的复合膜。     

溶胀MMT制备剥离型 MMT/MCPA6纳米复合材料

MMT经乙醇和水共溶胀后,将其均匀分散于己内酰胺熔体中;再利用浇铸工艺中的真空脱水去除水和乙醇,使己内酰胺在MMT层间阴离子开环聚合,制备了MMT/MCPA6纳米复合材料。利用X射线衍射仪、透射电镜、扫描电镜对复合材料的结构进行表征,利用力学性能测试仪、热失重分析仪及差示扫描量热仪对其性能进行测定。研究结果表明,MMT经溶胀后完全剥离并分散于MCPA6基体中,且能诱导γ晶型的形成,并提高了材料的结晶度;但MMT的添加破坏了复合材料晶体的规整性,阻碍了MCPA6分子链的运动,降低了其结晶速率。纳米级分散的MMT使复合材料的韧性略有下降,但强度得到了大幅度的提高,拉伸强度约提高了46.2%,弯曲强度约提高了26.2%,弯曲模量约提高了23.9%。纳米级分散的MMT在复合材料中起热阻隔的作用,少量的MMT可以使复合材料的热分解温度有所提高,残炭率增加,而且复合材料的维卡软化点温度提升至230℃,热变形温度提高至114℃。     

PET/MMT纳米复合材料的制备及性能研究

聚合物/蒙脱土(MMT)纳米复合材料,特别是剥离型的聚合物/MMT纳米复合材料的制备,是提高聚合物力学性能、耐热性能和阻隔性能的重要途径.然而,对于聚对苯二甲酸乙二醇酯(PET),由于其中等极性,难以得到剥离型的PET/MMT复合材料.本文采用PET缩聚阶段的催化剂醋酸锑对Na-MMT进行插层改性,并用原位聚合法分别制备了PET/Sb-MMT纳米复合材料和PET/Na-MMT纳米复合材料,采用XRD、TEM分析了PET/MMT复合材料的层间距和微观形貌,并通过DSC、TGA、水平燃烧实验和紫外一可见光透过率分析等方法分别考察了PET/MMT复合材料的结晶性能、热稳定性、阻燃性能以及紫外-可见光透光率.研究结果表明:醋酸锑插层MMT有效地提高了MMT的层间距;与PET/Na-MMT相比,PET/Sb-MMT纳米复合材料的层间距略有增加,且MMT片层有剥离趋势;同时,MMT的加人提高了PET的结晶速率,PET/Sb-MMT的热稳定性,阻燃性和透光率与PET/Na-MMT相比均有提高.     

PET/MMT纳米复合材料的制备及性能研究EI

聚合物/蒙脱土(MMT)纳米复合材料,特别是剥离型的聚合物/MMT纳米复合材料的制备,是提高聚合物力学性能、耐热性能和阻隔性能的重要途径.然而,对于聚对苯二甲酸乙二醇酯(PET),由于其中等极性,难以得到剥离型的PET/MMT复合材料.本文采用PET缩聚阶段的催化剂醋酸锑对Na-MMT进行插层改性,并用原位聚合法分别制备了PET/Sb-MMT纳米复合材料和PET/Na-MMT纳米复合材料,采用XRD、TEM分析了PET/MMT复合材料的层间距和微观形貌,并通过DSC、TGA、水平燃烧实验和紫外一可见光透过率分析等方法分别考察了PET/MMT复合材料的结晶性能、热稳定性、阻燃性能以及紫外-可见光透光率.研究结果表明:醋酸锑插层MMT有效地提高了MMT的层间距;与PET/Na-MMT相比,PET/Sb-MMT纳米复合材料的层间距略有增加,且MMT片层有剥离趋势;同时,MMT的加人提高了PET的结晶速率,PET/Sb-MMT的热稳定性,阻燃性和透光率与PET/Na-MMT相比均有提高.     

碱化蒙脱土改性浇铸尼龙6复合材料的 制备及性能研究

通过对MMT进行碱化处理,使MMT层间生成浇铸尼龙的催化剂己内酰胺钠,从而在MMT层间催化浇铸尼龙聚合,制备了MMT/MCPA6纳米复合材料。利用TG、DSC、HDT、SEM和力学性能测试表征了其结构与性能。结果表明,碱化MMT能诱导浇铸尼龙γ晶型的产生,提高材料的结晶度,使γ晶体含量随MMT质量分数的增加而增加。MMT起热阻隔作用,使复合材料的热分解温度有所提高,残炭率增加,而且复合材料的维卡软化点温度提升至231℃,热变形温度提高至114℃。碱化MMT能使复合材料韧性保持在一定水平的情况下,强度得到了大幅度的提高。     

Synthesis and properties of corn zein/montmorillonite nanocomposite films

The objectives of this study were to apply fabrication techniques for the zein montmorillonite (MMT) nanocomposite films and characterize the obtained nanocomposite films. Zein MMT nanocomposite films were successfully produced from solvent casting and blown extrusion methods. The two methods could mix the zein MMT resulting in partially exfoliated nanocomposite structures according to X-ray diffraction and transmission electron microscopy. The thermal resistant of the zein nanocomposite films fabricated from both methods improved as the MMT content increased. However, the mechanical and barrier properties showed non-linear relationships with the MMT loadings. The impact of MMT on properties of zein films strongly depended on the preparation techniques. This can be the good starting point to further study in depth insight of the controllable MMT rearrangement in zein films which will remarkably improve zein film properties for packaging applications.     

Facile fabrication of CdTe/montmorillonite nanocomposite films with stable photoluminescence properties

We report herein the facile synthesis of CdTe/montmorillonite (MMT) nanocomposite films via charge-charge interactions between the CdTe quantum dots (QDs) and MMT platelets. Firstly, negatively charged CdTe QDs were prepared with the use of thioglycolic acid (TGA) as ligand. Then hybrid of the as-prepared TGA-stabilized CdTe QDs with sodium montmorillonite (Na-MMT) and cetyltrimethylammonium-modified montmorillonite (CTA-MMT), respectively, afforded novel CdTe/MMT nanocomposite films. The structure and optical properties of CdTe/MMT nanocomposite films were thoroughly investigated by scanning electron microscope (SEM), ultraviolet transmittance reflection and photoluminescence (PL) measurements. Results showed that CdTe/(CTA-MMT) nanocomposite films exhibited highly enhanced PL intensity compared with CdTe/(Na-MMT) nanocomposite films. More importantly, CdTe QDs in CdTe/(CTA-MMT) nanocomposite films well maintained PL properties even after thermal annealing at 100 °C for 10 h.     

Synthesis and characterisation of starch/agar nanocomposite films for food packaging application

In the present work cassava starch/agar Ag and ZnO nanocomposite films were prepared by the solution casting method. The structural, physical and antimicrobial properties of the nanocomposite films were studied as a function of the concentration of Ag and ZnO nanoparticles. The results of the thermogravimetric analysis showed 8–15% degradation of both the nanocomposite films at 150°C endorsing the thermal stability of the films. Scanning electron microscopic analysis reveals the uniform blending of Ag and ZnO nanoparticles with a starch/agar matrix with tiny waves like appearance on the surface. The incorporation of Ag and ZnO nanoparticles in the film was found to reduce the moisture content, water solubility and water vapour permeability with increase in the concentration of Ag and ZnO nanoparticles. The growth kinetics study of Pseudomonas aeruginosa and Staphylococcus aureus in the presence of Ag and ZnO blended nanocomposite films showed promising results especially against Gram‐negative P. aeruginosa. Thus, the film synthesised in the present study bears the potential to be used as active packaging material to prevent food from bacterial contamination and spoilage.Inspec keywords: casting, microorganisms, scanning electron microscopy, nanoparticles, food preservation, solubility, thermal analysis, zinc compounds, food processing industry, food products, thermal stability, permeability, antibacterial activity, food packaging, contaminationOther keywords: water vapour permeability, food packaging, solution casting method, structural properties, physical properties, antimicrobial properties, water solubility, agar nanocomposite film, starch nanocomposite film, Pseudomonas aeruginosa, Staphylococcus aureus, bacterial contamination prevention, spoilage prevention, scanning electron microscopic analysis, thermogravimetric analysis, temperature 150.0 degC, Ag, ZnO     

聚乙烯醇/蒙脱土/山梨酸钾活性包装膜制备及释放

目的 通过制备聚乙烯醇（PVA）/蒙脱土（MMT）/山梨酸钾活性包装膜,考察其包装性能及山梨酸钾在膜材内的释放效果。方法 通过流延法制备含有不同浓度MMT的聚乙烯醇/山梨酸钾活性包装膜,分析活性包装膜的色度、透明度、拉伸性能和含水量,同时研究山酸钾在活性膜内向脂肪性食品模拟物中的释放行为。结果 通过添加MMT改善膜材的包装性能,MMT的添加在显著提高PVA膜拉伸强度的同时还降低了PVA膜的断裂伸长率,加深了膜材的色度,降低了膜的透明度;PVA膜的含水率随着MMT浓度的提高而降低。MMT的添加可明显改变山梨酸钾向脂肪类模拟物的释放行为,当MMT的质量分数为2%时明显地降低了山梨酸钾的释放量。结论 通过调整膜内MMT的浓度可以改变活性膜的色度、拉伸强度、含水量及膜内山梨酸钾的释放行为;使用Fickian第二定律模拟山梨酸钾释放是可靠的,可为山梨酸钾抗菌包装材料的进一步开发利用提供参考。     

Study on fracture behavior of surface treated montmorillonite/epoxy nanocomposites

It is known that the mechanical properties of clay-reinforced nanocomposites are significantly affected by the dispersion of clay particles in the matrix. In this study, the effect of surface-treatment of Montmorillonite (MMT) on the fracture behavior of MMT/epoxy nanocomposite was investigated. For this purpose, fracture tests were performed using samples with three different clay concentration level. After fracture tests, SEM analysis was made on the fracture surfaces to examine the fracture mechanism. It was found that the MMT treatment using 3-aminopropyltriethoxysilane enhanced the fracture toughness increased of the MMT/epoxy nanocomposite. This is due to the improved intercalation effect and interfacial strength between MMT and epoxy matrix.     

SiO2/聚（3-羟基丁酸酯-co-4-羟基丁酸酯）薄膜研究

目的研究纳米SiO2对可生物降解聚(3-羟基丁酸酯-co-4-羟基丁酸酯)(P34HB)包装膜结晶行为和力学性能的影响。方法采用溶液浇铸法制备SiO_2/P34HB纳米复合薄膜,利用红外光谱仪(FTIR)、扫描电镜(SEM)、正置热台显微镜(POM)、差示扫描量热仪(DSC)和万能力学试验机等研究纳米SiO_2对P34HB结构、结晶性和力学性能等的影响。结果纳米SiO_2在P34HB中起到异相成核的作用,SiO2/P34HB复合膜的结晶速率和结晶度得到明显改善。相比P34HB包装膜,当纳米SiO_2质量分数为2%时,SiO_2/P34HB复合膜的弹性模量和拉伸强度分别提高了72.7%和60.9%。结论获得了纳米SiO2改善可生物降解聚(3-羟基丁酸酯-co-4-羟基丁酸酯)包装膜结晶度和力学性能的最佳掺杂比例参数。     

Synthesis,Characterization and O2 Permeability of Shape Memory Polyurethane Films for Fresh Produce Packaging

The aim of this work was to investigate the effect of film formulations in an effort to obtain a fresh produce packaging film with increased temperature sensitivity for gas permeability. Series of shape‐memory polyurethane (SMPU) were synthesized using poly(ethylene glycol) (PEG), 1,6‐hexamethylene diisocyanate, 1,4‐butanediol and castor oil (CO) and casted into films. The changes in thermal, viscoelastic, shape‐memory properties and oxygen permeability of the films were studied. The polyurethane films with 1500 g mol^?1 PEG showed a phase transition temperature (switching temperature) between 20 and 27°C. The SMPU consisting of 50/50 CO/PEG had a log E′ value of 8.32 Pa and showed good elasticity as low density polyethylene. SMPU prepared from 1500 g mol^?1 PEG with 50/50 CO/PEG and 40/60 butanediol/(PEG + CO) ratios showed excellent shape‐memory properties with shape recovery ratio >85% and shape fixity ratio >90%. This film had higher oxygen permeability and showed up to 67% increase in Q₁₀ value for oxygen permeability compared with commercial packaging films like low density polyethylene. This film can be used to develop smart packaging with increased thermally responsive gas permeability to similar levels observed in respiration rates of fresh produce. Copyright © 2016 John Wiley & Sons, Ltd.     

Preparation and hydrophilicity of TiO2 sol-gel derived nanocomposite films modified with copper loaded TiO2 nanoparticles

In this study, TiO₂ nanocomposite films with 10 g/L of TiO₂ and copper loaded TiO₂ nanoparticles as nanofillers were deposited on the glass substrates using the sol gel dip-coating method. FE-SEM and UV-vis spectrophotometer were used to evaluate morphological and optical properties of copper loaded titania nanoparticles. In addition, XPS and water contact angle techniques were used to study the surface properties and superhydrophilicity of titania nanocomposite films, respectively. The results indicated that copper loaded TiO₂ nanoparticles had a significant effect on the hydrophilicity of nanocomposite film and maintaining it in a dark place for a long time (6.2 degree for titania nanocomposite films with copper loaded nanoparticle and 23.7 degree for nanocomposite film with titania nanoparticles).     

壳聚糖／大豆分离蛋白复合包装膜的制备与表征

采用壳聚糖(CS)和大豆分离蛋白(SPI)为基材,制备了可降解包装膜。用红外光谱、X射线衍射和扫描电镜对复合包装膜结构进行表征。对复合包装膜的拉伸性能和透光性能进行了测试和分析。结果表明:CS和SPI之间存在一定的相互作用;当SPI质量分数为10%时,复合包装膜的拉伸性能优于纯壳聚糖膜,透光性较纯壳聚糖膜略有下降。