Univ. Grenoble Alpes, CNRS, Grenoble INP, LGP2, F-38000 Grenoble, France.
Institut De Chimie Moléculaire Et Des Matériaux d'Orsay, Université Paris-Saclay, CNRS,, 91405 Orsay, France.
Carbohydr Polym. 2020 Apr 15;234:115899. doi: 10.1016/j.carbpol.2020.115899. Epub 2020 Jan 26.
Cellulose nanocrystals (CNCs) are used to design nanocomposites because of their high aspect ratio and their outstanding mechanical and barrier properties. However, the low compatibility of hydrophilic CNCs with hydrophobic polymers remains a barrier to their use in the nanocomposite field. To improve this compatibility, poly(glycidyl methacrylate) (PGMA) was grafted from CNCs containing α-bromoisobutyryl moieties via surface-initiated atom transfer radical polymerization. The novelty of this research is the use of a reactive epoxy-containing monomer that can serve as a new platform for further modifications or crosslinking. Polymer-grafted CNC-PGMA-Br prepared at different polymerization times were characterized by XRD, DLS, FTIR, XPS and elemental analysis. Approximately 40 % of the polymer at the surface of the CNCs was quantified after only 1 h of polymerization. Finally, nanocomposites prepared with 10 wt% CNC-PGMA-Br as nanofillers in a poly(lactic acid) (PLA) matrix exhibited an improvement in their compatibilization based on SEM observation.
纤维素纳米晶（CNC）因其高纵横比和出色的机械和阻隔性能而被用于设计纳米复合材料。然而，亲水性 CNC 与疏水性聚合物的低相容性仍然是其在纳米复合材料领域应用的障碍。为了提高这种相容性，通过表面引发原子转移自由基聚合，在含有 α-溴代异丁酰基的 CNC 上接枝了聚（甲基丙烯酸缩水甘油酯）（PGMA）。本研究的新颖之处在于使用了一种含有反应性环氧基团的单体，该单体可以作为进一步修饰或交联的新平台。通过 XRD、DLS、FTIR、XPS 和元素分析对不同聚合时间制备的接枝聚合物 CNC-PGMA-Br 进行了表征。仅聚合 1 小时后，在 CNC 表面就定量了约 40%的聚合物。最后，在聚乳酸（PLA）基体中，以 10wt% CNC-PGMA-Br 作为纳米填料制备的纳米复合材料，通过 SEM 观察显示其增容性得到了改善。
