Results 31 to 40 of about 5,506 (175)

Discovery and development of metallocene-based polyolefins with special properties [PDF]

Polyolefins Journal, 2015
Beside Ziegler-Natta and Phillips catalysts the development of methylaluminoxane (MAO) as cocatalyst in combination with metallocenes or other transition metal complexes for the polymerization of olefins has widely increased the possibilities in ...
Walter Kaminsky, Mercia Fernandes
doaj   +1 more source

A Brief Review of the Cocatalysts Types and their Performance in (Co)Polymerization Processes of Olefins: From Synthesis to Industrial Application [PDF]

Baspārish, 2022
In the past, most researchers believed that cocatalyst is a passive component that only has the task of "removing impurities" and "alkylating" the active centers of catalyst at the beginning of the polymerization and does not play a specific role in the ...
maryam masoori, Reza Rashedi, Abdolhannan Sepahi, Mohammad Hossein Jandaghian, Ehsan Nikzinat, Saeed Houshmand moayed   +5 more
doaj   +1 more source

Silicoaluminates as “support activator” systems in olefin polymerization processes [PDF]

, 2010
In this work we report the polymerization behaviour of natural clays (montmorillonites, MMT) as activating supports. These materials have been modified by treatment with different aluminium compounds in order to obtain enriched aluminium clays and to ...
Alba Carranza, María Dolores, Carmejo, C., Cuenca, T., Tabernero, Vanessa, Terreros, P.   +4 more
core   +2 more sources

Testing DFT ability to predict the stereoselectivity of group 4 metallocenes in propylene polymerization [PDF]

Polyolefins Journal, 2014
In this study we have tested the ability of a standard DFT computational protocol to reproduce the experimentally obtained stereoselectivity of 26 different C2-symmetric zirconocene catalysts active in propylene polymerization.
Naeimeh bahri-Laleh, Laura Falivene, Luigi Cavallo   +2 more
doaj   +1 more source

Introdução de catalisadores metalocênicos como estratégia competitiva da indústria de termoplásticos The introduction of metallocene catalysts as a competitive strategy of the thermoplastic industry

Polímeros, 1997
Recentes inovações tecnológicas no setor de polímeros levaram a novos catalisadores que poderão mudar a estrutura de toda a indústria. É feita uma análise das estratégias competitivas adotadas pelas empresas do setor e do impacto que a adoção dos ...
Francisco A. Ribeiro Fº, Maria José S. Ferreira Netto, Carlos A. Hemais   +2 more
doaj   +1 more source

Olefin Polymerizations Oriented by Rational Designs of Group-13 Compounds. [PDF]

Chem Rec
In coordination olefin polymerization chemistry, boron and aluminum compounds play important roles in both catalyst components and monomers. This personal account introduces our recent progress on the development of catalyst systems featured by the design of group‐13 counteranions, as well as the application of boronic acid‐crosslinked polyolefins to ...
Tanaka R, Zou Y.
europepmc   +2 more sources

Deprotonative C(sp3)/C(sp2)–H (Multi)Silylation of (Hetero)Arenes Mediated by NaTMP

Angewandte Chemie, Volume 138, Issue 21, 18 May 2026.
An operationally simple protocol using a strongly basic sodium amide in combination with sterically emcumbered silicon electrophiles enables the deprotonative C–H (multi)silylation of a myriad of (hetero)arenes. Mechanistic investigations highlight the pivotal role of steric and coordination effects in controlling the regioselectivity and efficiency of
David Sánchez‐Roa, Sophia Belrhomari, Ana McGinley, Clevin Anto Liju, Manting Mu, Max García‐Melchor, Eva Hevia   +6 more
wiley   +2 more sources

Catalisadores metalocênicos suportados para a produção de poliolefinas: revisão das estratégias de imobilização

Química Nova, 2011
The inadequacy of strategies used for the heterogeneization of metallocene catalysts is pointed out as one of the main causes of the lack of industrial employability of such polymerization catalysts.
Adriano G. Fisch, Nilo S. M. Cardozo, Argimiro R. Secchi, João H. Z. dos Santos   +3 more
doaj   +1 more source

Modification of ethylene-norbornene copolymer by Gamma irradiation [PDF]

Hemijska Industrija, 2006
The possibility of modifying polyethylene and many other polymers with high energy radiation has led to many useful applications. Due to their new combination of properties and the shortage of experimental data, the radiolysis of a new class of materials,
Kačarević-Popović Zorica M., Šećerov Bojana, Marinović-Cincović Milena T., Nedić Zoran, Jovanović Slobodan M.   +4 more
doaj   +1 more source

Modeling of synthesis and flow properties of propylene-diene copolymers [PDF]

, 2014
Copolymerization with nonconjugated dienes offers an attractive route for introducing long-chain branching in polypropylene. From a simplified set of rate equations for such copolymerization with a metallocene catalyst, we derive the probabilities of ...
Das, C, Read, DJ, Shirodkar, PP, Soulages, JM   +3 more
core   +1 more source