title: Reactive Nanoparticles Compatibilized Immiscible Polymer Blends: Synthesis of Reactive SiO2with Long Poly(methyl methacrylate) Chains and the in Situ Formation of Janus SiO2Nanoparticles Anchored Exclusively at the Interface.
abstract: The exclusive location of compatibilizers at the interface of immiscible binary polymer blends to bridge the neighboring phases is the most important issue for fabricating desirable materials with synergistic properties. However, the positional stability of the compatibilizers at the interface remains a challenge in both scientific and technical points of view due to the intrinsic flexibility of compatibilizer molecules against aggressive processing conditions. Herein, taking the typical immiscible poly vinylidene fluoride (PVDF)/polylactic acid (PLLA) blend as an example, we demonstrate a novel approach, termed as the interfacial nanoparticle compatibilization (IPC) mechanism, to overcome the challenges by packing nanoparticles thermodynamically at the interface through melt reactive blending. Specifically, we have first synthesized nanosilica with both reactive epoxide groups and long poly(methyl methacrylate) (PMMA) tails, called reactive PMMA-graft-SiO2(Epoxy-MSiO2), and then incorporated the Epoxy-MSiO2into the PVDF/PLLA (50/50, w/w) blends by melt blending. PLLA was in situ grafted onto SiO2by the reaction of the carboxylic acid groups with epoxide groups on the surface of SiO2. Therefore, the reacted SiO2particles were exclusively located at the interface by the formation of the Janus-faced silica hybrid nanoparticles (JSNp) with pregrafted PMMA tails entangled with PVDF molecular chains in the PVDF phase and the in situ grafted PLLA chains embedded in the PLLA phase. Such JSNp with a distinct hemisphere, functioning as compatibilizer, can not only suppress coalescence of PVDF domains by its steric repulsion but also enhance interfacial adhesion via the selective interactions with the corresponding miscible phase. The interfacial location of JSNp is very stable even under the severe shear field and annealing in the melt. This IPC mechanism paves a new possibility to use the various types of nanoparticles as both effective compatibilizers and functional fillers for immiscible polymer blends.
authors.affiliation: College of Materials, Chemistry and Chemical Engineering, Hangzhou Normal University , No. 16 Xuelin Rd., Hangzhou, Zhejiang 310036, P. R. China.|Shanghai Institute of Applied Physics, Chinese Academy of Sciences , Shanghai, 201800, P. R. China.|University of Chinese Academy of Sciences , Beijing, 100049, P. R. China.
authors.forename: Hengti
authors.initials: H
authors.lastname: Wang
authors.affiliation: College of Materials, Chemistry and Chemical Engineering, Hangzhou Normal University , No. 16 Xuelin Rd., Hangzhou, Zhejiang 310036, P. R. China.
authors.forename: Zhiang
authors.initials: Z
authors.lastname: Fu
authors.affiliation: College of Materials, Chemistry and Chemical Engineering, Hangzhou Normal University , No. 16 Xuelin Rd., Hangzhou, Zhejiang 310036, P. R. China.
authors.forename: Xuewen
authors.initials: X
authors.lastname: Zhao
authors.affiliation: College of Materials, Chemistry and Chemical Engineering, Hangzhou Normal University , No. 16 Xuelin Rd., Hangzhou, Zhejiang 310036, P. R. China.
authors.forename: Yongjin
authors.identifier: http://orcid.org/0000-0001-6666-1336
authors.initials: Y
authors.lastname: Li
authors.affiliation: Shanghai Institute of Applied Physics, Chinese Academy of Sciences , Shanghai, 201800, P. R. China.
authors.forename: Jingye
authors.initials: J
authors.lastname: Li
keywords: Janus SiO2 particles; immiscible polymer blends; in situ reaction; interfacial nanoparticle compatibilization; reactive blending