Macromolecular Reaction Engineering
Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Materials Science Weekly Newsletter
Recently Published Articles
- Thermal Behavior of Polyethylene Reactor Alloys Polymerized by Ziegler–Natta/Late Transition Metal Hybrid Catalyst
Saeid Ahmadjo, Samaneh Dehghani, Gholam Hossein Zohuri, Gholam Reza Nejabat, Hamed Jafarian, Mostafa Ahmadi and Seyed Mohammad Mahdi Mortazavi
Article first published online: 25 AUG 2014 | DOI: 10.1002/mren.201400024
Ziegler-Natta (ZN) and late transition metal (LTM) hybrid catalysts were synthesized and utilized in preparation of polyethylene (PE) reactor alloys. By changing reaction parameters, versatile thermal behavior from LTM-PE to ZN-PE could be obtained. The proposed method seems to be a promising approach for synthesis of tailor-made polyethylene in a single reactor.
- Poly(Urea–Urethane) Synthesis by Miniemulsion Polymerization Using Microwaves and Conventional Polymerization
Alexsandra Valério, Montserrat Fortuny, Alexandre F. Santos, Pedro H. H. Araújo and Claudia Sayer
Article first published online: 18 AUG 2014 | DOI: 10.1002/mren.201400029
The effect of microwave irradiation during step growth polymerization in miniemulsion to form poly(urea–urethane) nanoparticles is evaluated for different reaction temperatures and polyol types, including oil soluble and water soluble polyols.
- Modeling of RAFT Polymerization using Probability Generating Functions. Detailed Prediction of Full Molecular Weight Distributions and Sensitivity Analysis
Cecilia Fortunatti, Claudia Sarmoria, Adriana Brandolin and Mariano Asteasuain
Article first published online: 6 AUG 2014 | DOI: 10.1002/mren.201400020
A model based on the pgf transform is presented that simulates the RAFT polymerization according to any of the three main kinetic mechanisms discussed in the literature. The full MWD and the bivariate distribution corresponding to the two-arm intermediate adduct are obtained. A sensitivity analysis over several of the kinetic constants is also performed.
- Preparation of Nanocomposites of Polypropylene with Carbon Nanotubes via Masterbatches Produced by In Situ Polymerization and by Melt Extrusion
Rafael S. Araujo, Renato J. B. Oliveira and Maria de Fátima V. Marques
Article first published online: 6 AUG 2014 | DOI: 10.1002/mren.201400012
A new PP/multi-walled carbon nanotube (MWCNT) masterbatch is synthesized via in situ polymerization and compared with a masterbatch obtained by melt mixing. Both masterbatches are used for the realization of PP/MWCNT nanocomposites by mixing with a commercial PP in a extruder. It is shown that the use of the masterbatch synthesized in situ provides additional enhanced thermal stability and mechanical properties.
- High Temperature High Pressure Tandem Polymerization of Ethylene for Synthesis of Ethylene-1-Hexene Copolymers from Single Reactor with SNS-Cr and CGC-Ti Catalysts
Song Guo, Hong Fan, Zhiyang Bu, Bo-Geng Li and Shiping Zhu
Article first published online: 6 AUG 2014 | DOI: 10.1002/mren.201400027
Ethylene-1-hexene copolymers are synthesized from ethylene using the tandem catalyst system of SNS-Cr and CGC-Ti with MAO. The tandem polymerization is carried out in a high temperature high pressure solution process. Applying a short period of pre-trimerization effectively increases the 1-hexene content in copolymer and produces chains having uniform microstructure. The resulting copolymer exhibits competitive mechanical properties with a commercial ethylene-1-octene copolymer.