Abstract:
PURPOSE: Provided is a method for preparing a novel graft copolymer having high rubber content and improved natural color, as well as excellent in impact resistance and fluidity. CONSTITUTION: The method comprises the steps of (i) mixing 10-30 wt% of graft monomer mixture with fat-soluble thermal decomposition initiator with stirring, introducing the mixture into rubbery polymer, introducing molecular weight controlling agent and ion exchange water, elevating the temperature with stirring, and continuously stirring within 10 minutes when the temperature reaches 55-65 deg.C to swell most of the introduced graft monomer and polymerization initiator into rubber particles, and introducing an emulsifier and elevating a temperature of reactor to initiate a polymerization, thereby the first copolymer latex being produced; and (ii) introducing redox based catalyst mixture and polymerization initiator in a reactor in the presence of the first graft copolymer latex, stirring the mixture for 5-10 minutes, mixing 90-70 wt% of residual graft monomer mixture and molecular weight controlling agent with stirring, and continuously introducing the latter mixture over 2-5 hours and polymerization initiator at the same time for 2-5 hours to graft react the trace graft monomer and the polymerization initiator, thereby the second copolymer latex being produced.
Abstract:
A method for preparing thermoplastic resins is provided to produce the thermoplastic resins having both scratch resistance and transparency by polymerizing acrylic monomer in the presence of organophilic colloidal nanoparticles having vinyl groups. A method for preparing thermoplastic resins having improved scratch resistance includes the steps of: mixing water-dispersible colloidal nanoparticles with alcohol and ion exchanged water, dropping 5-25wt%, based on the water-dispersible colloidal nanoparticles, of an alkoxy silane compound, and performing a reaction to prepare colloidal nanoparticles having organophilic vinyl groups; and emulsion-polymerizing acrylic monomer and the colloidal nanoparticles having organophilic vinyl groups.
Abstract:
본 발명은 유화 중합을 통해 백색도와 표면 광택도가 우수한 열가소성 아크릴로니트릴-부타디엔-스티렌(ABS) 수지를 제조하는 방법에 관한 것이다. 본 발명은 부타디엔 고무질 중합체에 아크릴로니트릴 단량체, 스티렌 단량체, 및 아크릴레이트 단량체를 도입하여 유화중합법으로 그라프트 중합을 실시하는 것으로, 아크릴로니트릴 단량체와 스티렌 단량체 혼합물이 고무질 중합체 내부에서 중합되도록 하여 내충격성을 부여하는 1단계 반응, 아크릴레이트 단량체를 고무질 외부 표면에 고르게 중합되도록 하여 백색도를 부여하는 2단계 반응, 그리고 아크릴로니트릴 단량체와 스티렌 단량체가 고무질 외부 표면에 고르게 중합되도록 하여 수지의 광택도를 양호하게 유지시키기 위한 3단계 반응으로 이루어진다. 상기 방법에 의하여 제조된 그라프트 공중합체와 괴상중합법 의하여 SAN 수지를 혼합하여 백색도와 표면 광택도가 우수한 ABS계 열가소성 수지를 제조한다.