Results 41 to 50 of about 856 (180)

Facile Approach to Modulating Stereochemistry in Ring‐Opening Metathesis Polymerization of Cyclooctadiene

Journal of Polymer Science, EarlyView.
The stereochemistry of polybutadiene made by ring‐opening metathesis polymerization (ROMP) evolves both during and after polymerization, as secondary metathesis shifts cis‐rich kinetic products toward trans‐rich equilibrium compositions. By tuning catalyst identity, additives, temperature, and reaction time, polybutadienes with 28%–80% trans content ...
Amira S. Eldin, Michael D. Schulz
wiley   +1 more source

"Supported Ziegler-Natta catalysts from MgCl2·nROH precursors and its catalytic behaviors for diene copolymerization"

Hecheng xiangjiao gongye
The precursor MgCl2 · nROH of supported Ziegler Natta catalyst was prepared by chemical activation method, and different pre catalysts TiCl4/MgCl2 (C-Cat) were prepared by loading TiCl4.
FAN Xun-zhang, ZHAO Yuan-jin, LUO Shu-fang, HE Ai-hua?
doaj   +1 more source

From Cages to Sheets: Computational Elucidation of Methylaluminoxane Structure and Reactivity

ChemPlusChem, Volume 91, Issue 8, August 2026.
Methylaluminoxane (MAO), the dominant cocatalyst in metallocene‐based olefin polymerization, has resisted structural characterization for decades. This review traces the computational journey from early cage and nanotube proposals to the identification of two‐dimensional aluminoxane sheets as the thermodynamically preferred motif, and how this ...
Mikko Linnolahti, Perttu Hanhisalo, Aleksi Vähäkangas   +2 more
wiley   +1 more source

Chemical state analysis of magnesium-supported Ziegler-Natta catalyst by soft X-ray emission spectrometer (SXES) after contact with alkyl aluminum [PDF]

Polyolefins Journal
This report is on the characterization of active Ti center in heterogeneous Ziegler-Natta catalysts with Soft X-ray Emission Spectrometer (SXES). Since titanium in the catalyst has various chemical bonds, it is important to grasp the chemical bond state.
Masayoshi Saito, Hiroshi Kashimura, Takuo Kataoka, Masahide Murata, Yusuke Sakuda, Hiroyuki Yamada, Hideyuki Takahashi   +6 more
doaj   +1 more source

Acyclic Hydrocarbon α,ω‐Dienes: From Biomass and Plastic Upcycling to Carbocycles, Precision Polymers, and Cross‐Linked Elastomers

ChemSusChem, Volume 19, Issue 14, 29 July 2026.
Hydrocarbon α,ω‐dienes are mainly produced from steam‐cracking derivatives, but high costs, complexity, and environmental impact limit their use. This review highlights sustainable paths from biomass and plastic upcycling, and surveys catalytic transformations into carbocycles and specialty polymers, emphasizing their role as modular building blocks ...
Rosa Villaccio, Giuseppe Leone
wiley   +1 more source

Advantages of an Emulsion‐Produced Ziegler‐Natta Catalyst Over a Conventional Ziegler‐Natta Catalyst

Macromolecular Materials and Engineering, 2005
AbstractSummary: Self‐supported and MgCl2‐supported Ziegler‐Natta catalysts, produced by two catalyst synthesis methods are compared. Borealis Polymers OY (Finland), who supplied the catalysts, developed the catalyst synthesis methods. The first method (Method One) is based on an emulsion system and consists of an in situ single step preparation.
Mohammed Abboud, Peter Denifl, Karl‐Heinz Reichert   +2 more
openaire   +1 more source

Theoretical Study of the Halogen Concentration Effect on the 1,3-Butadiene Polymerization Catalyzed by the Neodymium-Based Ziegler–Natta System

Reactions
In this work, an attempt is made to theoretically substantiate the experimentally known facts of the influence of halogen concentration on the catalytic properties of the neodymium-based Ziegler–Natta system.
Alexey N. Masliy, Ildar G. Akhmetov, Andrey M. Kuznetsov, Ilsiya M. Davletbaeva   +3 more
doaj   +1 more source

Impact of Commercial Polyolefin Architecture and Composition on Its Ability to Compatibilize High‐Density Polyethylene/Isotactic Polypropylene Blends

Journal of Polymer Science, Volume 64, Issue 14, Page 3057-3072, 15 July 2026.
This research elucidates the relationship between the molecular structure of commercially available ethylene–propylene copolymers and an ethylene/1‐olefin copolymer and its ability to compatibilize high‐density polyethylene/isotactic polypropylene blends. These findings indicate that the compatibilization of these blends with random copolymers benefits
Bailey Eberle, Susan K. Houston, Hannah Giffin, Mark Dadmun   +3 more
wiley   +1 more source

Organic Photoelectrochemical Cells Beyond Performance: Interface and Catalyst Engineering for Durability

Advanced Energy Materials, Volume 16, Issue 25, 1 July 2026.
Organic photoelectrochemical cells based on π‐conjugated semiconductors offer a versatile platform for solar fuel generation. This review outlines operating principles, device architectures, and key metrics, and highlights advances in p‐ and n‐type photoelectrodes, interfacial engineering, and catalyst integration.
Jaehyeong Kim, Jung Min Ha, Yeonjeong Lee, Seung Won Oh, Wangyeon Lee, Munsu Kwon, Soonyong Lee, Jin Young Kim, Han Young Woo   +8 more
wiley   +1 more source

Ti+4 determination in Ziegler–Natta polymerization catalysts via UV‒vis spectroscopy method [PDF]

Polyolefins Journal
The determination of Ti+4 in Ziegler–Natta catalysts is highly relevant for industrial plants that use Ziegler–Natta (ZN) catalysts based on TiCl4 as a source of titanium.
Jonas Biagini, Joao Henrique dos Santos
doaj   +1 more source