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可生物降解聚乳酸纤维的新进展 总被引:7,自引:0,他引:7
综述了聚乳酸纤维生产的新状况,概括了市场动向、生产原料及方法、产品性能及应用等方面的新进展,指出了我国目前的研究状况和以后的开发方向。 相似文献
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聚乳酸纤维的染色性能 总被引:7,自引:0,他引:7
用9只不同结构的分散染料对聚乳酸纤维(PLA)进行染色,结果发现,对结晶度50%的PLA,有两只染料的上色率超过60%;对结晶度21%的PLA,有4只染料的上色率超过60%。用12只偶氮染料和13只蒽醌染料染成1/1标准浓度的PLA织物,其光褪色机理和影响因素与聚酯纤维和醋酸纤维相同,但褪色速度较快,耐晒牢度要差1—2级;PLA纤维染色应选用高浓度、高耐晒牢度的中温型分散染料。碱性溶液会引起PLA织物水解,60℃以上水解速度加快。 相似文献
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介绍了聚乳酸及其纤维的研发现状、聚乳酸的合成工艺、聚乳酸纤维纺丝工艺、聚乳酸纤维物理机械性能及用途。聚乳酸的合成以丙交酯开环聚合法(两步法)应用最多;聚乳酸纤维的纺丝以熔融纺丝法较好;纤维的物理机械性能与聚酯纤维相似,而其染色性、吸湿性、可生物降解性优于聚酯纤维。 相似文献
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绿色合成纤维--聚乳酸纤维 总被引:7,自引:0,他引:7
面对席卷全球的绿色浪潮,一种绿色的合成纤维——聚乳酸纤维,在纤维行业中越来越多被人们所重视。本文在介绍聚乳酸纤维的结构的基础上,详细地总结了聚乳酸纤维的包括物理性能、降解性能和安全性能在内的各种性能,具体地讨论了聚乳酸纤维的合成和纺丝过程,指出聚乳酸纤维具有广阔的应用前景和深远的生态意义,但当前的关键问题是降低合成聚乳酸树脂的成本。 相似文献
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介绍了聚对苯撑苯并二噁唑(PBO)纤维的性能特点,以及单体和聚合物合成、液晶纺丝制造工艺,综述了PBO纤维近30年来在国内外的技术进展及其应用前景,并指出了PBO纤维的竞争形势及开发风险,对今后国内PBO纤维产业的发展提出了一些建议。 相似文献
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可生物降解纤维--聚乳酸(PLA)纤维第Ⅱ报.性能特征及其应用前景 总被引:3,自引:1,他引:3
介绍了生物可降解纤维--聚乳酸纤维的性能特征及其在混纺、非织造布、服装、装饰、医疗等领域的应用前景. 相似文献
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以左旋乳酸(L?LA)和乙醇酸(GA)为原料,利用一步法熔融共聚合成聚(乳酸?乙醇酸)(PLLGA)共聚物,通过差示扫描量热仪(DSC)对共聚物薄膜的结晶性能进行了表征,并利用Avrami方程对其进行了等温结晶动力学研究,通过万能拉伸试验机和压差法气体透过仪对共聚物薄膜的力学性能和气体阻隔性能进行测试。结果表明,PLLGA共聚物薄膜中GA的引入对材料结晶性能有较大影响,在GA含量为4 %(摩尔分数,下同)的PLLGA中,GA表现为成核剂作用,共聚物结晶比纯聚左旋乳酸(PLLA)薄膜快,半结晶时间减少;而在GA含量为8 %的PLLGA中,GA则表现出限制分子链运动的作用,破坏共聚物分子间的规整度,导致材料结晶性能大幅度降低,处于非晶态;随着GA含量的增加,PLLGA薄膜的拉伸强度和弹性模量逐步下降,而断裂伸长率大幅度增加,GA含量为8 %的PLLGA的断裂伸长率达到了130.1 %,是纯PLLA薄膜的21.3倍;同时,PLLGA薄膜的气体阻隔性显著增加,5 ℃时,相比于纯PLLA薄膜,GA含量为8 %的PLLGA薄膜的O2、CO2、N2透过量分别降低了47 %、41 %和39 %。 相似文献
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Mihir Sheth R. Ananda Kumar Vipul Dav Richard A. Gross Stephen P. McCarthy 《应用聚合物科学杂志》1997,66(8):1495-1505
Poly(lactic acid) (PLA) and poly(ethylene glycol) (PEG) were melt-blended and extruded into films in the PLA/PEG ratios of 100/0, 90/10, 70/30, 50/50, and 30/70. It was concluded from the differential scanning calorimetry and dynamic mechanical analysis results that PLA/PEG blends range from miscible to partially miscible, depending on the concentration. Below 50% PEG content the PEG plasticized the PLA, yielding higher elongations and lower modulus values. Above 50% PEG content the blend morphology was driven by the increasing crystallinity of PEG, resulting in an increase in modulus and a corresponding decrease in elongation at break. The tensile strength was found to decrease in a linear fashion with increasing PEG content. Results obtained from enzymatic degradation show that the weight loss for all of the blends was significantly greater than that for the pure PLA. When the PEG content was 30% or lower, weight loss was found to be primarily due to enzymatic degradation of the PLA. Above 30% PEG content, the weight loss was found to be mainly due to the dissolution of PEG. During hydrolytic degradation, for PLA/PEG blends up to 30% PEG, weight loss occurs as a combination of degradation of PLA and dissolution of PEG. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 1495–1505, 1997 相似文献
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Biodegradable poly(lactic acid) (PLA) composites were prepared using an innovative combination of wood fiber (WF) and 1,3,2,4‐bis(3,4‐dimethylobenzylideno)sorbitol (DMDBS). DMDBS acted as an effective nucleating agent, which improved the mechanical properties and slowed down the degradation of the WF/PLA composites. The enzymatic degradation of the composites was examined by immersing in proteinase K or cellulase buffer. The presence of DMDBS resulted in a 26.7% increase of the crystallinity compared to the WF/PLA composites. The increase in crystallinity enhanced the thermal stability and tensile strength of the WF/DMDBS/PLA composites by 8.5%. The durability of the WF/DMDBS/PLA composites after nucleated modification was enhanced after enzymolysis. After nucleated modification, the surface of the WF/PLA composites showed clear cracks due to degradation, while these appeared about 2 weeks later in the case of the WF/DMDBS/PLA composites. The results revealed that the introduction of cellulase degraded WF in the composites, which increased hydrolysis or enzymolysis sites. The combination of nucleated modification and enzyme buffer gave an expanded downstream application of WF/PLA composites in packaging and agricultural materials. © 2019 Society of Chemical Industry 相似文献
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聚乳酸/聚乙烯醇纳米纤维的制备及结构 总被引:1,自引:0,他引:1
以二甲基亚砜为溶剂,制备不同配比的聚乳酸(PLLA)和聚乙烯醇(PVA)的混合溶液,静电纺丝制得PLLA/PVA纳米纤维。采用红外光谱仪、原子力显微镜等对PLLA/PVA纳米纤维结构与性能进行了表征。结果表明:PLLA/PVA纳米纤维中PVA上的羟基与PLLA上的羰基形成了氢键,PLLA与PVA之间存在一定的相互作用,但PLLA/PVA纳米纤维存在相分离现象;混合溶液的PLLA质量分数为11%,PVA质量分数为8%时可以得到较好的PLLA/PVA纳米纤维,但PVA质量分数为6%时出现液滴及珠丝,PVA质量分数为4%时,不能制得纳米纤维。 相似文献
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Distillers dried grains with solubles (DDGS), an ethanol industry coproduct, is used mainly as a low‐value feedstuff. Poly(lactic acid) (PLA) is a leading biodegradable polymer, but its applications are limited by its relatively high cost. In this study, low‐cost, high‐performance biodegradable composites were prepared through thermal compounding of DDGS and PLA with methylene diphenyl diisocyanate (MDI) as a coupling agent. Mechanical, morphological, and thermal properties of the composites were studied. The coupling mechanism of MDI in the PLA/DDGS system was confirmed via Fourier‐transform infrared spectra. The PLA/20% DDGS composite with 1% MDI showed tensile strength (77 MPa) similar to that of pure PLA, but its Young's modulus was 25% higher than that of pure PLA. With MDI, strong interfacial adhesion was established between the PLA matrix and DDGS particles, and the porosity of the composites decreased dramatically. Crystallinity of PLA in the composites was higher than that in pure PLA. Composites with MDI had higher storage moduli at room temperature than pure PLA. This novel application of DDGS for biocomposites has significantly higher economic value than its traditional use as a feedstuff. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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Relationship between the crystallization behavior of poly(ethylene glycol) and stereocomplex crystallization of poly(L‐lactic acid)/poly(D‐lactic acid) 下载免费PDF全文
Chunyan Luo Minrui Yang Wei Xiao Jingjing Yang Yan Wang Weixing Chen Xia Han 《Polymer International》2018,67(3):313-321
Poly(l ‐lactic acid) (PLLA) is a good biomedical polymer material with wide applications. The addition of poly(ethylene glycol) (PEG) as a plasticizer and the formation of stereocomplex crystals (SCs) have been proved to be effective methods for improving the crystallization of PLLA, which will promote its heat resistance. In this work, the crystallization behavior of PEG and PLLA/poly(d ‐lactic acid) (PDLA) in PLLA/PDLA/PEG and PEG‐b‐PLLA/PEG‐b‐PDLA blends has been investigated using differential scanning calorimetry, polarized optical microscopy and X‐ray diffraction. Both SCs and homocrystals (HCs) were observed in blends with asymmetric mass ratio of PLLA/PDLA, while exclusively SCs were observed in blends with approximately equal mass ratio of PLLA/PDLA. The crystallization of PEG was only observed for the symmetric blends of PLLA39k/PDLA35k/PEG2k, PLLA39k/PDLA35k/PEG5k, PLLA69k/PDLA96k/PEG5k and PEG‐b‐PLLA31k/PEG‐b‐PDLA27k, where the mass ratio of PLLA/PDLA was approximately 1/1. The results demonstrated that the formation of exclusively SCs would facilitate the crystallization of PEG, while the existence of both HCs and SCs could restrict the crystallization of PEG. The crystallization of PEG is related to the crystallinity of PLLA and PDLA, which will be promoted by the formation of SCs. © 2017 Society of Chemical Industry 相似文献
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A systematic investigation of the rheological and thermal properties of nanocomposites prepared with poly(lactic acid) (PLA), poly(butylene succinate) (PBS), and organically modified layered silicate was carried out. PLA/PBS/Cloisite 30BX (organically modified MMT) clay nanocomposites were prepared by using simple melt extrusion process. Composition of PLA and PBS polymers were fixed at a ratio of 80 to 20 by wt % for all the nanocomposites. Rheological investigations showed that high clay (> 3 wt %) contents strongly improved the viscoelastic behavior of the nanocomposites. Percolation threshold region was attained between 3 and 5 wt % of clay loadings. With the addition of clay content for these nanocomposites, liquid‐like behavior of PLA/PBS blend gradually changed to solid‐like behavior as shown by dynamic rheology. Steady shear showed that shear viscosity for the nanocomposites decreased with increasing shear rates, exhibiting shear‐thinning non‐Newtonian behavior. At higher clay concentrations, pseudo‐plastic behavior was dominant, whereas pure blend showed almost Newtonian behavior. Thermogravimetric analysis revealed that both initial degradation temperature (at a 2% weight loss) and activation energy of thermal decomposition nanocomposite containing 3 wt % of C30BX were superior to those of other nanocomposites as well as to those of PLA/PBS blend. Nanocomposite having 1 wt % of C30BX did not achieve expected level of thermal stability due to the thermal instability of the surfactant present in the organoclay. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献