METHOD FOR PRODUCING HOLLOW RESIN PARTICLE

• Main Authors: HIRATA TAKESHI, IGA TAKASHI
• Format: Patent
• Language: English; Japanese
• Published: 31.08.2020
• Subjects: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CHEMISTRY; COMPOSITIONS BASED THEREON; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; THEIR PREPARATION OR CHEMICAL WORKING-UP; THEIR RELEVANT APPARATUS; TRANSPORTING

To provide a method for producing hollow resin particles which can remove a hydrocarbon-based solvent contained as a non-reactive solvent in a hollow part of obtained precursor particles in short time even when suspension polymerization is performed using a monomer composition having a large content ratio of a crosslinkable monomer, and can suppress aggregation of particles generated in drying treatment.SOLUTION: A method for producing hollow resin particles includes: a step of preparing a polymerizable monomer containing a non-crosslinkable monomer and a crosslinkable monomer, a hydrocarbon-based solvent and a suspension liquid containing an aqueous medium; a step of subjecting the suspension liquid to polymerization reaction to prepare a precursor composition containing precursor particles which have a hollow part and include the hydrocarbon-based solvent; a step of replacing the aqueous medium that is a continuous phase of the precursor composition with a polar solvent to prepare a polar solvent-based dispersion body; and a step of removing the hydrocarbon-based solvent included in the precursor particles, in which 35-95 pts.mass of the crosslinkable monomer is contained with respect to 100 pts.mass of the total mass of the polymerizable monomer in the mixed liquid.SELECTED DRAWING: Figure 1A 【課題】架橋性単量体の含有割合が大きい単量体組成物を用いて懸濁重合を行った場合でも、得られた前駆体粒子の中空部に非反応性溶媒として含まれている炭化水素系溶剤を短時間で除去することが可能であるとともに、乾燥処理時に発生する粒子の凝集を抑制することが可能な中空樹脂粒子の製造方法を提供する。【解決手段】中空樹脂粒子の製造方法は、非架橋性単量体及び架橋性単量体を含む重合性単量体、炭化水素系溶剤、並びに、水系媒体を含む懸濁液を調製する工程、前記懸濁液を重合反応に供することにより、中空部を有し炭化水素系溶剤を内包する前駆体粒子を含む前駆体組成物を調製する工程、前記前駆体組成物の連続相である水系媒体を極性溶剤に置換することにより極性溶剤系分散体を調製する工程、及び、前駆体粒子に内包される炭化水素系溶剤を除去する工程を含み、前記混合液中に、前記重合性単量体の総質量１００質量部に対し前記架橋性単量体を３５〜９５質量部含む。【選択図】図１Ａ