|
|
- 2015
纳米纤维素晶须增强增韧聚(L-乳酸)复合材料的制备与表征
|
Abstract:
通过酸解法制备了具有纳米尺寸和一定长径比针棒状的纳米纤维素晶须(NCW), 利用NCW表面的羟基引发L-丙交酯开环聚合, 合成了表面接枝聚(L-乳酸)(PLLA)链段的接枝纤维素晶须(g-NCW);采用溶液浇铸法制备了PLLA膜以及不同配比的NCW/PLLA和g-NCW/PLLA复合膜.对接枝改性前后的NCW的形貌与性能进行了表征, 研究了复合膜的形貌、结晶性能、热稳定性、亲/疏水性和拉伸性能.结果表明: NCW的形貌与结晶性能在接枝改性后变化不大, 但在乙醇和PLLA溶液中的分散性得到明显改善;当NCW与L-丙交酯的物质的量之比为1∶5时, g-NCW表面PLLA链段的接枝率约为23.61%.NCW和g-NCW作为异相成核剂, 显著提高了PLLA基体的结晶速率;并且, 加入晶须改善了材料的亲水性和热稳定性.添加一定量的NCW和g-NCW到PLLA中, 可有效增强增韧PLLA基体;随着晶须含量增加, 复合膜的拉伸强度和断裂能先增大后下降;当NCW和g-NCW的质量分数为5%时, NCW/PLLA和g-NCW/PLLA复合膜的拉伸强度和断裂能分别达到22.02 MPa和20.01 MPa以及102.39 J/m3和117.83 J/m3, 均达到最大值.由于g-NCW在基体中良好的分散性以及与基体间的界面结合, g-NCW/PLLA复合膜的拉伸强度和韧性明显优于相应的纯PLLA和NCW/PLLA膜. The needle rod-like cellulose whiskers (NCW) with nano size and certain length-diameter ratiowere prepared by acid hydrolysis, and then were surface modified with poly (L-lactic acid) (PLLA) segments through thering-opening polymerization of L-lactide initiated by surfacehydroxyl groups to obtain grafted cellulose whiskers(g-NCW). PLLA membrane and NCW/PLLA and g-NCW/PLLA composite membranes with different ratios were prepared by solution casting method. Morphologies and properties of the modified and unmodified NCW were observed, and the morphologies, crystallization properties, thermostability, hydrophilicity/hydrophobicity and tensile properties of the composite membranes were studied too. The results show that the morphology and crystallization property of NCW change little after graft modification, but the dispersion of g-NCW in ethanol and PLLA solution is improved significantly. The grafting percentage of PLLA segments on surface of g-NCW is 23.61% as the ratio of amount of substance of NCW to L-lactide is 1∶5. The crystallization rateof PLLA matrix increases significantly due to the heterogeneous nucleating effect of the NCW and g-NCW. In addition, the hydrophilicity and thermostability of material are improved by the introduction of the whiskers.When adding some content of NCW and g-NCWto PLLA, the strength and toughness of the PLLA matrix are evidently improved. With the content of whiskers increasing, the tensile strength and breaking energy increase first and then decrease for NCW/PLLA and g-NCW/PLLA composite membranes, as the mass fraction of NCW and g-NCW is 5%, the highest tensile strength and breaking energy of 22.02 MPa and 20.01 MPa, 102.39 J/m3 and 117.83 J/m3 are obtained for NCW/PLLA and g-NCW/PLLAcomposite membranes respectively. Due to the excellent dispersionof g-NCW in matrix and interfacial adhesion, the tensile strength and toughness of g-NCW/PLLA composite membranes are obviously superior to those of the pure PLLA and NCW/PLLA
| [1] | Garlotta D. A literature review of poly (lactic acid)[J]. Journal of Polymers and the Environment, 2001, 9(2): 63-84. |
| [2] | Li H H, Luo B H, Qin X P, et al. Preparation of PLLA /g-HNTs composite nanofiber membranes by electrospinning and studies on their properties[J]. Acta Polymerica Sinica, 2015(1): 31-40 (in Chinese). 李慧华, 罗丙红, 秦小鹏, 等. 静电纺丝法制备PLLA/g-HNTs复合纳米纤维膜及其性能研究[J]. 高分子学报, 2015(1): 31-40. |
| [3] | Balakrishnan H, Hassan A, Imran M, et al. Toughening of polylactic acid nanocomposites: A short review[J]. Polymer Plastics Technology and Engineering, 2012, 51(2): 175-192. |
| [4] | Ma H B, Tai Z X, Sun D F, et al. Study on the preparation and biology properties of polylactic acid/nano-hydroxyapatite/graphene oxide nanocomposite membranes[J]. Materials Review, 2011, 25(5): 19-22 (in Chinese). 马海冰, 邰志新, 孙东飞, 等. 聚乳酸/纳米羟基磷灰石/氧化石墨烯纳米复合膜的制备及生物性能研究[J]. 材料导报, 2011, 25(5): 19-22. |
| [5] | Niu X F, Feng Q L, Wang M B, et al. Chitosan microspheres/nanohydroxyapatite/collagen/polylactide composite[J]. Acta Materiae Compositae Sinica, 2009, 26(2): 143-148 (in Chinese). 牛旭锋, 冯庆玲, 王明波, 等. 微囊化壳聚糖/纳米羟基磷灰石/胶原/聚乳酸复合材料[J]. 复合材料学报, 2009, 26(2): 143-148. |
| [6] | Zhuang W, Zhang J H, Liu J, et al. Preparation and characterization of nano-TiO2/poly(L-actide) composites[J]. Acta Materiae Compositae Sinica, 2008, 25(3): 8-11 (in Chinese). 庄韦, 张建华, 刘靖, 等. 纳米TiO2/聚乳酸复合材料的制备和表征[J]. 复合材料学报, 2008, 25(3): 8-11. |
| [7] | Ma H B, Su W X, Tai Z X, et al. Preparation and cytocompatibility of polylactic acid/hydroxyapatite/graphene oxide nanocomposite fibrous membrane[J]. Chinese Science Bulletin, 2012, 23(57): 3051-3058. |
| [8] | Che J, Qin F, Yang R J. Polylactide/montmorillonite nanocomposites in-situ polymerizetion and characterization[J]. Journal of Materials Engineering, 2011(1): 28-37 (in Chinese). 车晶, 秦凡, 杨荣杰. 聚乳酸/蒙脱土纳米复合材料的原位聚合及表征[J]. 材料工程, 2011(1): 28-37. |
| [9] | Xu W, Luo B H, Wen W, et al. Surface modification of halloysite nanotubes with L-lactic acid: An effective route to high-performance poly(L-lactide) composites[J]. Journal of Applied Polymer Science, 2014, 132(7): 1-10. |
| [10] | Miao C W, Hamad W. Cellulose reinforceed polymer composites and nanocomposites: A critical review[J]. Celloluse, 2013, 20(5): 2221-2262. |
| [11] | Avik K, Ruhul A K, Stephane S, et al. Mechanical and barrier properties of nanocrystal-line cellulose reinforced chitosan based nanocomposite films[J]. Carbohydrate Polymers, 2012, 90(4): 1601-1608. |
| [12] | Neethu N, Muthunarayanan M, In-Kyu P, et al. Pectin carboxymethyl cellulose/microf-brillated cellulose composite scaffolds for tissue engineering[J]. Carbohydrate Polymers, 2013, 98(1): 877-885. |
| [13] | Pooyan P R, Tannenbaum H G. Mechanical behavior of a cellulose-reinforced scaffold in vascular tissue engineering[J]. Journal of the Mechanical Behavior of Biomedical Materials, 2011, 7: 50-59. |
| [14] | Liu D Y, Yuan X W, Bhatta-Charyya D. The effects of cellulose nanowhiskers on electrospun poly (lactic acid) nanofibres[J]. Journal of Materials Science, 2012, 47(7): 3159-3165. |
| [15] | Lu Z X, Fan L W, Zheng H Y, et al. Preparation, characterization and optimization of nanocellulose whiskers by simultaneously ultrasonic wave and microwave assisted[J]. Bioresource Technology, 2013, 146: 82-88. |
| [16] | Li J L, Chen G X, Ye D Y. Progress of research on preparation and application of nanocellulose whiskers[J]. Chemistry and Industry of Forest Products, 2010, 30(2) : 121-125 (in Chinese). 李金玲, 陈广祥, 叶代勇. 纳米纤维素晶须的制备及应用的研究进展[J]. 林产化学与工业, 2010, 30(2): 121-125. |
| [17] | He Y L, Liao X X, Huang K L, et al. Study process of microcrystalline cellulose[J]. Technology & Development of Chemical Industry, 2010, 39(1): 12-16 (in Chinese). 何耀良, 廖小新, 黄科林, 等. 微晶纤维素的研究进展[J]. 化工技术与开发, 2010, 39(1): 12-16. |
| [18] | Elena T, Long J, Michael P W. Crystallization kinetics of poly(3-hydroxybutyrate-co-3-hydro-valerate) cellulose nanowhiskers composite[J]. Carbohydrate Polymers, 2012, 90(1): 541-550. |
| [19] | Tang A M, Yao B T, Xu L Q, et al. Synthesis and characterization of nano-crystalline cellulose/CdS optoelectric nano-composites[J]. Chinese Journal of Materials Research, 2013, 27(2): 178-182 (in Chinese). 唐爱民, 姚邦涛, 许立群, 等. 纳米纤维素/CdS纳米复合光电材料的制备和性能[J]. 材料研究学报, 2013, 27(2): 178-182. |
| [20] | Zeng Q H, Luo B H, Yang Y, et al. Prearation and characterization of high molecular weight poly(L-lactic acid) under microwave irrdiation[J]. Functional Materials, 2007, 6(28): 972-975 (in Chinese). 曾庆慧, 罗丙红, 杨媛, 等. 低温常压下高分子量左旋聚乳酸的微波合成及表征[J] . 功能材料, 2007, 6(28): 972-975. |
| [21] | Wang X D, Peng X F, Lu J F, et al. Analysis of contact angle hysteresis on rough surfaces[J]. Journal of Thermal Science and Technology, 2003, 2(3): 230-234 (in Chinese). 王晓东, 彭晓峰, 陆建峰, 等. 粗糙表面接触角滞后现象分析[J]. 热科学与技术, 2003, 2(3): 230-234. |
| [22] | Cui X X, Qu P, Chen P, et al. Study on the degradation of cellulose nanowhiskers/poly(1actic acid)composites[J]. New Chemical Materials, 2010, 38(4): 73-76 (in Chinese). 崔晓霞, 曲萍, 陈品, 等. 可生物降解聚乳酸/纳米纤维素复合材料的亲水性和降解性[J]. 化工新型材料, 2010, 38(4): 73-76. |
| [23] | Zhang Z D, Chen X M, Dong Y, et al. Nano-CaCO3 filled powdered rubber composite particles reinforcing and toughening polyvinyl chloride[J]. Acta Materiae Compositae Sinica, 2012, 29(6): 19-25 (in Chinese). 张周达, 陈雪梅, 董源, 等. 纳米碳酸钙-粉末橡胶复合粒子增强增韧聚氯乙烯[J]. 复合材料学报, 2012, 29(6): 19-25. |
