title: Preparation of polyurea/melamine formaldehyde double-layered self-healing microcapsules and investigation on core fraction.
abstract: Moisture curing type self-healing microcapsules become more attractive, while instability of active core material crippled the efficiency of self-healing behaviour. Polyurea (PU)/melamine formaldehyde (MF) double-layered self-healing microcapsules containing isophorone diisocyanate (IPDI) core with high and stable core fraction were prepared. The structure, morphology, particle size and distribution were studied with Fourier transform infra-red spectroscopy, optical microscopy, scanning electron microscopy and Mastersizer 3000. The influences of process conditions were investigated to uncover the principle of core fraction and morphology of microcapsules. The core fraction of microcapsules was reduced with the increase of ageing time, and microcapsules prepared with ice-bath, polyetheramine (PEA) and prepolymer of melamine formaldehyde (P-MF) had higher core fraction and better morphology. PEA D230 and 1500 rpm agitation rate were chosen according to optimised trade-offs in the core fraction and morphology of the microcapsules.
authors.affiliation: a School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou , China ;
authors.forename: Yaoqiang
authors.initials: Y
authors.lastname: Ming
authors.affiliation: a School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou , China ;
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Hu
authors.affiliation: b Department of Chemical Engineering and Materials Science , Wayne State University , Detroit , MI , USA.
authors.forename: Junheng
authors.initials: J
authors.lastname: Xing
authors.affiliation: a School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou , China ;
authors.forename: Minghua
authors.initials: M
authors.lastname: Wu
authors.affiliation: a School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou , China ;
authors.forename: Jinqing
authors.initials: J
authors.lastname: Qu
mesh_terms: D002214:Capsules / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D014227:Triazines / Q000737:chemistry*
chemical_list: D002214:Capsules; D011108:Polymers; D014227:Triazines; C504353:melamine formaldehyde; C045786:polyurea
keywords: Moisture curing; PEA; PU/MF double-layered; core fraction; self-healing microcapsules