For the purpose of increasing molecular weight of poly (phenylene sulfide), PPS, copolymerization method and two-stage polymerization method were investigated. The thermal properties and molecular weight of copolymers and homopolymers were determined by DSC thermal analyzer and high temperature (210℃) GPC with 1-chloronaphthalene as eluent, respectively. Copolymers were prepared by the reaction of Na₂S · 9H₂O (SS) with p-dichlorobenzene (p-DCB) and m-dichlorobenzene (m-DCB) or 1,2,4-trichlorobenzene (TCB) in N-methyl-2-pyrrolidinone (NMP) solvent at 250℃. In case of the PPS copolymers synthesized by the reaction of m-DCB/p-DCB/SS, molecular weight, T_g's, and T_m's were lower than those of PPS homopolymer. On the other hand, the T_g's of copolymer synthesized by the reaction of TCB/p-DCB/SS increased with increasing amount of TCB comonomer and the use of minor amount (2 mole% ) of TCB comonomer gave higher molecular weight polymer than PPS homopolymer. Two-stage polymerization of PPS reported Kureha company and a simplified direct two-stage polymerization were compared with one-stage polymerization of PPS with increased reaction time or m-DCB and TCB copolymerization. It was found that PPS homopolymer by the simplified two-stage polymerization method gave higher molecular weight PPS sample than those by the one-stage polymerization with increased reaction time or copolymerizations.

Poly(phenylene sulflde), PPS의 고분자량화를 위해 공중합법 및 2단계 중합법을 조사하였다. 이들 공중합체 및 단독중합체의 분자량은 1-chloronaphthalene을 eluent로 하여 고온(210℃) GPC를 사용하여 측정하였고, 열적 성질은 DSC로 조사하였다. 먼저 NMP 용매를 사용하여 m-dichlorobenzene (m-DCB) 혹은 1,2,4-trichlorobenzene (TCB)을 P-dichlorobenzene (p-DCB)과 함께 sodium sulfide (SS)로 공중합한 경우, m-DCB/p-DCB/SS 공중합 반응으로 생성된 PPS 공중합체들의 중합수율과 분자량 및 T_g와 T_m은 감소하였지만, TCB/p-DCB/SS 공중합체인 경우에는 T_g는 증가하고 T_m은 감소하였으며 TCB 함량이 2mole%에서 분자랑이 증가하였다가 4mole% 이상일 때는 감소함이 관찰되었다. 또 2단계 중합법에서는 일본 Kureha사의 특허에 의한 2단계 중합법과 이의 변형인 직접 2단계 중합법을 같은 반응 조건하의 1단계 중합법과 비교하였다. 중합 공정이 간략화된 직접 2단계 중합법에 의한 PPS 단독중합체의 경우 고온 GPC분석 결과, 반응시간을 연장한 1단계 중합법, Kureha사 2단계 중합법 및 공중합의 경우보다 분자량이 높게 나타났다.

Keywords: poly (phenylene sulfide); copolymerization; two-stage polymerization; thermal properties