본 연구에서는 루프반응기를 사용한 열분해의 운전조건인 반응시간, 예비가열단계의 유무, 교반시작온도, 예비가열단계시간, 최종 교반속도가 점도, 연화점, 수평균분자량(Mn), 질량평균분자량(Mw) 그리고 다분산성지수(Mw/Mn)와 같은 PE 왁스제품의 물성에 미치는 영향에 대해 연구하였다. 반응시간이 증가할수록 제품의 점도와 연화점은 감소하였다. 교반시작온도를 증가시키면 열전달속도가 감소하기 때문에 최종 제품의 점도와 Mn과 Mw는 모두 증가하였으며, 예비가열단계시간이 60분일 때 최종 제품의 점도와 Mn과 Mw는 각각 최저값을 보였다. 최종 교반속도를 증가시키면 열전달속도가 향상되기 때문에 최종 제품의 점도와 Mn과 Mw 그리고 Mw/Mn는 모두 감소하였다. 상부공간의 깊이는 내용물의 온도가 본격적인 분해반응이 일어나는 대략 380 ℃에 도달한 때에 최저값을 보여주었다. 운전조건의 변화는 최종 제품의 연화점과 수율에 거의 영향을 주지 않았다.

The effects of the operation conditions, such as reaction time, introduction of preheating stage, temperature of starting stir, preheating stage time, and final stir speed, on the physical properties of the polyethylene wax producted in a loop reactor by thermal degradation were investigated. As the reaction time increased, the viscosity and the softening point of the products were decreased. The viscosity, Mn and Mw of the final products were increased with an increase of the temperature of starting stir due to a decrease of heat transfer rate. When the preheating stage time was 60 min, the viscosity, Mn and Mw of the final products showed the minimum values, respectively. As the final stir speed increased, the viscosity, Mn, Mw and Mw/Mn of the final_x000D_ products were decreased due to an increase of heat transfer rate. The deepness of the top void showed the minimum value when the medium temperature reached at about 380 ℃ because thermal degradation of the medium took place in good earnest at the temperature. The effects of the operation conditions on the softening point of the final products and the yield were negligible.

Polyethylene Wax Thermal Degradation Stepped Heating Method Polydispersity Index

Erkron D, Encyclopedia of Chemical Technology, 3rd ed., Vol. 24, John Wiley & Sons, New York, 466 (1984)
Buechner O, Immel W, "Production of Low Molecular Weight Waxy Polyethylenes," U.S. Patent, 3,557,074 (1971)
Eberhardt GG, "Method of Producing Straight Chain Waxes by Catalytic Polymerization of Ethylene," U.S. Patent, 3,567,703 (1971)
Ratzsch M, Grundmann H, "Process for Producing Waxlike Low Molecular Ethylene Polymers and Copolymers," U.S. Patent, 3,441,628 (1969)
Shin DK, Kim YC, Shim SM, Choi JW, "A Study on the Preparation of Medium Molecular Polyethylene Wax," MOST (1983)
Nishimoto H, Senda H, "Preparation of Low Molecular Weight Polyolefin," Japan Patent, Publication No. 03-062804 (1991)
Kossiakoff A, Rice FO, J. Am. Chem. Soc., 65, 590 (1943) 
Guy L, Fixari B, Polymer, 40(10), 2845 (1999) 
Choi KH, HWAHAK KONGHAK, 39(6), 667 (2001)
Murty MVS, Grulke EA, Bhattacharyya D, Polym. Degrad. Stabil., 61, 421 (1998)