化工进展 ›› 2018, Vol. 37 ›› Issue (05): 1875-1880.DOI: 10.16085/j.issn.1000-6613.2017-1361

• 材料科学与技术 • 上一篇    下一篇

聚乳酸多孔微球的制备及其表征

刘瑞来   

  1. 武夷学院福建省生态产业绿色技术重点实验室, 生态与资源工程学院, 福建 武夷山 354300
  • 收稿日期:2017-07-04 修回日期:2017-11-17 出版日期:2018-05-05 发布日期:2018-05-05
  • 通讯作者: 刘瑞来(1984-),男,博士,副教授,主要从事功能高分子材料研究。
  • 作者简介:刘瑞来(1984-),男,博士,副教授,主要从事功能高分子材料研究。E-mail:wyulrl@163.com。
  • 基金资助:
    国家自然科学基金(51406141)、福建省自然科学基金(2018J05092)、福建省高校产学研合作(2018Y4011)、福建省教育厅项目(JAT170595,JAT170596)、国家大学生创新性实验(201710397014)及武夷学院引进人才项目(YJ201703,YJ201704)。

Fabrication and characterization of poly(L-lactic acid) porous microspheres

LIU Ruilai   

  1. College of Ecological and Resources Engineering, Fujian Provincial Key laboratory of Eco-Industrial Green Technology, Wuyi University, Wuyishan 354300, Fujian, China
  • Received:2017-07-04 Revised:2017-11-17 Online:2018-05-05 Published:2018-05-05

摘要: 以聚乳酸(PLLA)/四氢呋喃(THF)为淬火溶液,无其他添加剂条件下,通过低温淬火、萃取、洗涤和干燥得到直径为30.92μm±1.55μm的PLLA多孔微球,多孔微球由直径为0.34μm±0.06μm向外辐射的纤维组成。偏光显微镜表明多孔微球为球晶结构。XRD结果表明,多孔微球属于α晶型,晶粒尺寸大小为17.25nm。DSC结果表明,PLLA多孔微球的结晶度为36.05%。与熔融挤出造粒得到PLLA原料(结晶度小于10%)相比,低温淬火得到的多孔微球的结晶度大大提高。N2吸附-脱附结果分析表明,多孔微球的平均孔径和孔体积分别为42.92nm和0.1135cm3/g,大部分为大孔和介孔结构,比表面积和孔隙率分别为14.18cm2/g和93.15%。采用等温DSC模拟低温淬火过程研究了PLLA在THF溶液中结晶动力学,利用Avrami方程得到Avrami指数n平均值为2.29,说明PLLA在THF溶液中为异相成核和三维生长。

关键词: 结晶, 纳米材料, 乳酸, 多孔微球, 低温淬火

Abstract: Poly (L-lactic acid) porous microspheres with diameter of 30.92μm±1.55μm were prepared from its tetrahydrofuran solution through four steps of low-temperature quenching,extraction,washing and drying while without the assistance of other additives. The microspheres were composed of radicalized nanofibers with diameter of 0.34μm±0.06μm. The polarized optical microscope observations show that the PLLA porous microspheres are spherulites,while the XRD patterns show that they belong to α form with grain size of 17.25nm. DSC results show that the crystallinity of the microspheres obtained from low-temperature quenching are 36.05%,higher than the raw PLLA prepared by the melt-extrusion. N2 adsorption-desorption results indicate that the average pore size and volume of the microspheres are 42.92nm and 0.1135cm3/g,respectively,and most pores are macropore and mesopore. The specific surface area and porosity are 14.18m2/g and 93.15%,respectively. DSC was used to study the isothermal crystallization kinetics of PLLA in THF solutions to mimic the low-temperature quenching process. The Avrami equation was used to analyze the data. Avrami exponent n was 2.29,indicating that the nucleation and crystal growth mechanism were heterogenous nucleation and three-dimensional,respectively.

Key words: crystallization, nanomaterials, poly(L-lactic acid), porous microspheres, low-temperature quenching

中图分类号: 

京ICP备12046843号-2;京公网安备 11010102001994号
版权所有 © 《化工进展》编辑部
地址:北京市东城区青年湖南街13号 邮编:100011
电子信箱:hgjz@cip.com.cn
本系统由北京玛格泰克科技发展有限公司设计开发 技术支持:support@magtech.com.cn