Chinese Journal of Chemical Engineering ›› 2019, Vol. 27 ›› Issue (10): 2574-2580.doi: 10.1016/j.cjche.2018.10.023

• Materials and Product Engineering • Previous Articles     Next Articles

Synthesis of melamine-formaldehyde microcapsules containing oil-based fragrances via intermediate polyacrylate bridging layers

Yanping He1, Shunzhi Yao1, Junzheng Hao1, Hong Wang2, Linhua Zhu1, Tian Si1, Yanlin Sun1, Jianhao Lin1   

  1. 1 School of Chemical Engineering, Kunming University of Science and Technology, Chenggong Campus, Kunming 650504, China;
    2 Faculty of Science, Kunming University of Science and Technology, Chenggong Campus, Kunming 650504, China
  • Received:2018-09-19 Revised:2018-10-25 Online:2019-10-28 Published:2020-01-17
  • Contact: Yanlin Sun, Jianhao Lin;
  • Supported by:
    Supported by the National Natural Science Foundation of China (21466016, 21577053); and the Natural Science Foundation of Yunnan Province (2016FB024).

Abstract: A general and versatile strategy to prepare melamine-formaldehyde (MF) microcapsules encapsulating oil-based fragrances by combining solvent evaporation and in situ polymerization was proposed in this work. The oil-based fragrance was pre-encapsulated by an inner polyacrylate membrane via solvent evaporation, followed by in situ polymerization of MF precondensates as an outer shell. The polyacrylate membrane is used as an intermediate bridging layer to stabilize the oil-based fragrance, and to provide driving forces for in situ polymerization of MF precondensates through electrostatic attractions between carboxyl groups and ammonium ions. It was demonstrated that MF microcapsules containing clove oil were prepared successfully. The amount and the composition of the intermediate polyacrylate bridging layer were critical. Smooth and sphere-shaped MF-clove oil microcapsules were prepared when the weight ratio of polyacrylate to clove oil was over 60 wt% and the concentration of acrylic acid (AA) increased to 10 wt% in polyacrylate. In addition, MF microcapsules containing sunflower oil and hexyl salicylate were prepared by using this method. The work suggests that this new approach can be potentially used to encapsulate various core materials, tuning the shell properties of microcapsules such as thickness, mechanical strength and release properties.

Key words: Melamine formaldehyde, Microcapsule, Oil-based fragrance, Particle, Polymers, Synthesis