Journal of Coatings Technology and Research
·
2017
·Vol. 15
·期 3
·505-514
·
IF 1.557
Zhao Yuan,Huang Chongxing,Bei Ronghua,Su Hongxia,Wang Shuangfei
Silicon oxide (SiO
x
) films are widely used as barrier layers in different types of commodity packaging and have caught the interest of manufacturers and researchers alike owing to their high barrier functionality, good acid and alkali resistance, ability to withstand high-temperature and microwave treatments, and good transparency. In this study, we first synthesized polylactic acid (PLA) films by extrusion calendaring and then deposited a SiO
x
layer on the PLA films by plasma-enhanced chemical vapor deposition to prepare SiO
x
/PLA composite films. We then evaluated the barrier functionality of the SiO
x
layer and elucidated its underlying mechanism. We also analyzed its effect on the mechanical properties of the composite films by comparing the oxygen and water vapor transmission rates, soil degradation performances, and surface morphologies of the two types of synthesized films (uncoated and coated with SiO
x
). The results showed that, because of the SiO
x
layer, the barrier properties and mechanical properties of the SiO
x
/PLA composite films were better than those of the uncoated films. In particular, the oxygen and water vapor transmission rates of the composite films were approximately 8–10 and 6–8 times lower, respectively, than those of the uncoated PLA films. In addition, the SiO
x
layer lowered the rate of soil degradation of the composite films, owing to which the weight-loss rates of the composite films were also lower than those of the uncoated films. Further, the tensile strengths and elongations at break of the composite films were higher because of the SiO
x
layer. Graphical
研究领域:
材料科学
·
高分子材料
·
包装工程
·
表面改性
·
生物降解材料
✓ 已验证
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2018
·
IF 5.158
Le Li,Rui-Ying Bao,Tao Gao,Zheng-Ying Liu,Bang-Hu Xie,Ming-Bo Yang,Wei Yang
Improving the physical properties of biobased polymers using bionanofillers is essential to preserve its biodegradability. This work presents a dopamine-induced functionalization of cellulose nanocrystals (CNCs) with polyethylene glycol (PEG), to enhance the crystallization, mechanical and barrier properties of poly( L -lactic acid) (PLLA) bionanocomposites. The effect of molecular weight of grafted PEG on the properties of PLLA is also studied. PEGylation of CNCs significantly enhance the crystallization of PLLA, especially for CNCs functionalized with PEG of lower molecular weight, which lead to balanced strength and ductility, and 66.4% reduction in the oxygen permeability coefficient at a low content of 0.5 wt %. Moreover, 168% improvement of ductility for PLLA can be obtained by CNCs functionalized with longer PEG chains. The surface functionalization of CNCs proposed here opens up a green avenue towards designing and fabricating fully bio-based, high-barrier and low-cost polymer nanocomposites for packaging applications.
研究领域:
高分子材料
·
纳米复合材料
·
生物基包装
·
材料科学
·
聚合物改性
·
结晶动力学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 12
·51827
·
IF 3.125
Yuan Li,Lu Zhang,Fayong Li,Ke Wang,Xiaoru Wu,Hailu Liu,Bibo Long,Yang Zhao,Dong Xie,Junjia Chen
The hydrophobic modification of cellulose nanofibers (CNF) was carried out via free radical polymerization using methyl methacrylate (MMA) as the monomer to improve the compatibility between CNF and poly lactic acid (PLA). Followed by the preparation of the novel nanocomposites in combination of the organic montmorillonite and the substrate. The resulting nanocomposites were then coated on paper surface using a cast-coating process in an attempt to improve the barrier properties towards water vapor and oxygen. In addition, the composite films are prepared via a solution casting method. The water vapor transmission rate (WVTR), water vapor permeability (WVP), oxygen transmission rate (OTR), and tensile strength of the as-prepared films were systematically measured. The corresponding results demonstrated that the WVTR, WVP and OTR decreased with the addition of a certain content of MCNF in coatings. 0.2 wt% MCNF is the optimum content, showing the best gas resistance and tensile performance. The lowest value of WVTR and WVP are 10.30 g/(m 2 ⋯24 h) and 3306.58 g⋯μm/(m 2 ⋯24 h) for films with 0.2 wt% MCNF added, which is 88.23% and 26.05% lower than that of PLA composite film without NFC.
研究领域:
高分子材料
·
纳米复合材料
·
包装材料
·
表面涂层
·
生物基材料
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2018
·
IF 5.091
Siyuan Dong,Yingqi Jia,Xiaozhi Xu,Jianeng Luo,Jingbin Han,Xiaoli Sun
Poly(ethylene terephthalate) (PET) generally suffers from low crystallization rate and long molding duration, which as a result limit its application as engineering plastics. To overcome these drawbacks, series of PET/layered double hydroxide (LDH) nanocomposites were prepared by a solution blending process. The effect of metal composition (MgAl and CaAl) and organo-modification (stearic acid intercalated) for LDH fillers on the crystallization behavior of the nanocomposites was investigated. It was revealed that, compared with PET/CaAl-LDH, the PET/MgAl-LDH nanocomposite exhibits a higher crystallization temperature and faster crystallization rate, which is associated with the superior nucleation ability of MgAl-LDH. The nucleation mechanism of PET induced by LDHs was explored by means of Avrami equation and theory of Hoffman-Lauritzen, pointing out that the incorporation of LDHs reduce the free energy of nucleation and the fold surface free energy of PET. In order to improve the compatibility between LDH and PET, stearic acid (SA) intercalated MgAl-LDH was prepared and filled into PET matrix. The resultant PET/MgAl-LDH-SA shows a further enhanced crystallization temperature and accelerated crystallization rate, in comparison with PET/MgAl-LDH nanocomposites. In addition, the thermal stability, gas barrier and mechanical properties of PET/LDH composites were improved upon incorporation of LDH fillers.
研究领域:
高分子科学
·
材料化学
·
纳米复合材料
·
结晶动力学
·
聚合物物理
·
功能材料
·
工程塑料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）