Self-Stabilized Precipitation Polymerization of Vinyl Chloride and Maleic Anhydride

Abstract

Self-stabilized precipitation (2SP) polymerization, a powerful tool for synthesizing and functionalizing uniform polymeric microspheres, is commonly applied in the heterogeneous copolymerization of olefinic compounds with maleic anhydride (MAH). In the present work, we exploited the 2SP polymerization of the vinyl chloride monomer (VCM) with MAH using bis­(4-tert-butylcyclohexyl) peroxydicarbonate (TBCP) as the initiator in an isoamyl acetate/n-hexane binary mixture solvent. The effects of polymerization conditions such as the solvent composition, monomer feed ratio, total monomer concentration, and initiator concentration on the size and morphology of the resultant poly­[(vinyl chloride)-co-(maleic anhydride)] (PVM) microspheres were investigated systematically. The results showed that clean and well-dispersed PVM microspheres with particle sizes ranging from 185 to 335 nm were successfully prepared when the solubility parameter of the mixture solvent was in the range of 15.92–16.22 MPa1/2. By simply tuning the monomer feed ratios, PVM copolymers (Mn = 14400–21400 g/mol) with a high content of MAH (∼50 mol %) were obtained, which was difficult to achieve either in conventional suspension or in emulsion polymerization. More interestingly, the resultant PVM microspheres showed excellent water solubility in alkaline solution when the molar fraction of MAH in copolymers was more than 40%, making the anhydride-containing PVM microspheres highly attractive as promising functional materials.

Facile and High-Yield Synthesis of Monodisperse and Heat-Resistant Polymaleimide Microspheres by Self-Stabilized Precipitation Polymerization

“…A series of styrene/maleic anhydride (St/MAH, SMA) copolymer microspheres , with tunable particle sizes, molecular weights, and copolymer composition have been prepared by the 2SP process. Apart from St, MAH can also copolymerize with other electron-donating monomers such as vinyl acetate, vinyl chloride, and aromatic olefins , and terpolymerize with St/acrylamide and St/isoprene by the 2SP process, leading to the formation of polymer particles with different chemical compositions and molecular structures.…”

Synthesis of Poly[(vinyl chloride)-co-(vinyl polydimethylsiloxane)] via Precipitation Polymerization and Its Lubrication Behavior in the PVC Matrix

“…Recently, our group has expanded 2SP technology in the homo- or copolymerization of vinyl chloride monomer (VCM) to prepare PVC and its copolymers. Interestingly, the obtained PVC and its copolymers exhibited a lower degree of polymerization, a lower melt viscosity, a small particle size (100–800 nm), and good matrix compatibility, showing potential application value in processing aids and other special fields. − …”

Synthesis of a Vinyl Chloride-Methyl Acrylate Random Copolymer with Controllable Copolymer Composition and Its Processing Features in Rigid PVC

“…Recently, the nonaqueous polymerization of VC, which was conducted in organic solvents as an alternative to water, attracted extensive attention in the preparation of PVC resin due to its remarkable advantages such as direct formation of solid polymeric particles and facile separation of polymer products. − Moreover, the overall energy consumption in a nonaqueous process is only about 60% of that in a conventional aqueous polymerization process, and virtually all the organic solvent can be fully recycled. Bao and co-workers reported the work on the nonaqueous polymerization of VC in n -butane using sorbitan monostearate and poly­(vinyl alcohol) as suspending agents, in which PVC chains precipitate from a VC/ n -butane mixed medium to form primary aggregates at a very low polymerization conversion and primary aggregates aggregate to form the primary particles, which further aggregate to form the grains .…”