Discrete copper(ii)-formate complexes as catalytic precursors for photo-induced reversible deactivation polymerization

2016 ◽  
Vol 7 (1) ◽  
pp. 191-197 ◽  
Author(s):  
Vasiliki Nikolaou ◽  
Athina Anastasaki ◽  
Francesca Brandford-Adams ◽  
Richard Whitfield ◽  
Glen R. Jones ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Metal Salt ◽  
Good Control ◽  
Molecular Weight Distributions ◽  
Weight Distributions ◽  
Reversible Deactivation

Traditional copper-mediated reversible deactivation polymerization techniques (RDRP) employ various components mixedin situ(e.g.ligand, metal salt, additional deactivation speciesetc.) in order to achieve good control over the molecular weight distributions.

In Situ Synthesis of Polystyrene/SiO2 Hybrid Composites via a 'Grafting Through' Strategy Based on Nitroxide-mediated Radical Polymerisation

2008 ◽  
Vol 16 (9) ◽  
pp. 621-626 ◽  
Author(s):  
Yunpu Wang ◽  
Yongqian Shen ◽  
Xiaowei Pei ◽  
Wenjuan Zhang ◽  
Yuli Wei ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Hybrid Composites ◽  
Hybrid Particles ◽  
Molecular Weight Distributions ◽  
Weight Distributions ◽  
Radical Polymerisation ◽  
Soft Shell ◽  
Grafting Through ◽  
Vinyl Group

Polymer-grafted nanosilica hybrid composites that possess a hard backbone of nanosilica and a soft shell of brush-like polystyrene (PSt) were prepared via a ‘grafting through’ strategy based on nitroxide-mediated radical polymerisation (NMRP) using 2,2,6,6-tetramethylpiperidine-iV-oxyl (TEMPO) as the mediator. Two steps were used to graft PSt chains to the surface of nanosilica: anchoring of vinyltrimethoxysilane onto the surface of nanosilica, and then using TEMPO to trap the radicals produced by the reaction of benzoyl peroxide (BPO) with styrene and the vinyl group in grafted vinyltrimethoxysilane molecules. Finally, well-controlled molecular weight (Mn) and narrow molecular weight distributions (Mw/Mn) of PSt chains were grown from the surface of nanosilica. The prepared PSt-g–SiO2 hybrid particles have been extensively characterised by FTIR, XPS, TGA, and TEM.

Reversible-deactivation radical polymerization of chloroprene and the synthesis of novel polychloroprene-based block copolymers by the RAFT approach

RSC Advances ◽  
2014 ◽  
Vol 4 (98) ◽  
pp. 55529-55538 ◽  
Author(s):  
Jia Hui ◽  
Zhijiao Dong ◽  
Yan Shi ◽  
Zhifeng Fu ◽  
Wantai Yang
Keyword(s):  
Molecular Weight ◽  
Block Copolymers ◽  
Radical Polymerization ◽  
Molecular Weights ◽  
Molecular Weight Distributions ◽  
Weight Distributions ◽  
Reversible Deactivation ◽  
Raft Agent ◽  
Reversible Deactivation Radical Polymerization

Novel, well-defined PCP-based block copolymers (PSt-b-PCP and PMMA-b-PCP) with controlled number averaged molecular weights and molecular weight distributions can be prepared, employing EPDTB and CPDB, respectively, as the initial RAFT agent.

scholarly journals Tailoring Polymer Dispersity by Controlled Radical Polymerization: A Versatile Approach

2020 ◽  
Author(s):  
Richard Whitfield ◽  
Kostas Parkatzidis ◽  
Nghia Truong ◽  
Tanja Junkers ◽  
Athina Anastasaki
Keyword(s):  
Molecular Weight ◽  
Kinetic Modelling ◽  
Raft Polymerization ◽  
Good Control ◽  
Chain Extension ◽  
Molecular Weight Distributions ◽  
Polymer Properties ◽  
Reversible Addition ◽  
Wide Range ◽  
Weight Distributions

<p>Dispersity (<i>Ɖ</i>) can significantly affect polymer properties and is a key parameter in materials design; however, current methods do not allow for the comprehensive control of dispersity. They are limited in monomer scope, may require the use of flow-based systems and/or additional reagents (<i>e.g.</i> termination agents or co-monomers), and are often accompanied by multimodal molecular weight distributions, low initiator efficiencies or poor end-group fidelity. Herein, we report a straightforward and versatile batch method based on reversible addition-fragmentation chain transfer (RAFT) polymerization which enables good control over <i>Ɖ</i> of a wide range of monomer classes, including acrylates, acrylamides, methacrylates and styrene. In addition, our methodology is compatible with more challenging monomers such as methacrylic acid, vinyl ketone and vinyl acetate. Control over <i>Ɖ</i> is achieved by mixing two RAFT agents with sufficiently different transfer activities in various ratios, affording polymers with monomodal molecular weight distributions over a broad dispersity range (<i>Ɖ</i> ~ 1.09-2.10). Our findings were further supported by simulations through the use of deterministic kinetic modelling which was fully in line with our experimental data, further confirming the power of our methodology. The robustness of the concept is further demonstrated by the preparation of well-defined block copolymers via chain extension of all polymers regardless of the initial <i>Ɖ</i>.</p>

scholarly journals Tailoring Polymer Dispersity by Controlled Radical Polymerization: A Versatile Approach

2020 ◽  
Author(s):  
Richard Whitfield ◽  
Kostas Parkatzidis ◽  
Nghia Truong ◽  
Tanja Junkers ◽  
Athina Anastasaki
Keyword(s):  
Molecular Weight ◽  
Kinetic Modelling ◽  
Raft Polymerization ◽  
Good Control ◽  
Chain Extension ◽  
Molecular Weight Distributions ◽  
Polymer Properties ◽  
Reversible Addition ◽  
Wide Range ◽  
Weight Distributions

<p>Dispersity (<i>Ɖ</i>) can significantly affect polymer properties and is a key parameter in materials design; however, current methods do not allow for the comprehensive control of dispersity. They are limited in monomer scope, may require the use of flow-based systems and/or additional reagents (<i>e.g.</i> termination agents or co-monomers), and are often accompanied by multimodal molecular weight distributions, low initiator efficiencies or poor end-group fidelity. Herein, we report a straightforward and versatile batch method based on reversible addition-fragmentation chain transfer (RAFT) polymerization which enables good control over <i>Ɖ</i> of a wide range of monomer classes, including acrylates, acrylamides, methacrylates and styrene. In addition, our methodology is compatible with more challenging monomers such as methacrylic acid, vinyl ketone and vinyl acetate. Control over <i>Ɖ</i> is achieved by mixing two RAFT agents with sufficiently different transfer activities in various ratios, affording polymers with monomodal molecular weight distributions over a broad dispersity range (<i>Ɖ</i> ~ 1.09-2.10). Our findings were further supported by simulations through the use of deterministic kinetic modelling which was fully in line with our experimental data, further confirming the power of our methodology. The robustness of the concept is further demonstrated by the preparation of well-defined block copolymers via chain extension of all polymers regardless of the initial <i>Ɖ</i>.</p>

scholarly journals Visible light induced controlled cationic polymerization by in situ generated catalyst from manganese carbonyl

2019 ◽  
Vol 55 (49) ◽  
pp. 7045-7048 ◽  
Author(s):  
Jiajia Li ◽  
Mengmeng Zhang ◽  
Xiangqiang Pan ◽  
Zhengbiao Zhang ◽  
Sébastien Perrier ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Cationic Polymerization ◽  
Irradiation Time ◽  
Light Radiation ◽  
Vinyl Ethers ◽  
Mild Conditions ◽  
Molecular Weight Distributions ◽  
Weight Distributions ◽  
Manganese Carbonyl

Controlled cationic polymerization of various vinyl ethers is achieved under light radiation, utilizing commercially available reagents, under mild conditions and the molecular weight distributions can be modulated by simply regulating the irradiation time.

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