Cationic polymerization of 1,3-dioxolane and 1,3-dioxepane. Application to graft and block copolymer synthesis

1985 ◽  
Vol 63 (1) ◽  
pp. 264-269 ◽  
Author(s):  
Léonard C. Reibel ◽  
Claude P. Durand ◽  
Emile Franta
Keyword(s):  
Molecular Weight ◽  
Block Copolymer ◽  
Block Copolymers ◽  
Cationic Polymerization ◽  
Weight Control ◽  
Graft Copolymers ◽  
Living Conditions ◽  
Molecular Weight Control ◽  
Central Block ◽  
Living Polymers

The cationic polymerization of 1,3-dioxolane and 1,3-dioxepane has been investigated to prepare "living" polymers and then to use them for copolymerization. Carbenium hexafluoroantimonate salts that are good initiators for tetrahydrofuran polymerization have been tested but produce unsatisfactory results with these acetals. In contrast, triflic anhydride, another good initiator for tetrahydrofuran polymerization, allows molecular weight control. Attempts to prepare block copolymers of two acetals by adding the second one to the first one under living conditions were unsuccessful because of randomization through transacetalization. Block copolymers containing a central block of polydioxepane and outer blocks of 1,2-dimethoxyethylene could be prepared by addition of the latter to living polydioxepane. Active polydioxolane reacts readily with polystyrene and leads to the formation of graft copolymers in the absence of gel.

scholarly journals Block Copolymer Synthesis by the Combination of Living Cationic Polymerization and Other Polymerization Methods

2021 ◽  
Vol 9 ◽  
Author(s):  
Asmita Dey ◽  
Ujjal Haldar ◽  
Priyadarsi De
Keyword(s):  
Molecular Weight ◽  
Block Copolymer ◽  
Block Copolymers ◽  
Cationic Polymerization ◽  
Chemical Properties ◽  
Good Control ◽  
Vital Role ◽  
Living Cationic Polymerization ◽  
Wide Range ◽  
Post Modification

The foremost limitation of block copolymer synthesis is to polymerize two or more different types of monomers with different reactivity profiles using a single polymerization technique. Controlled living polymerization techniques play a vital role in the preparation of wide range of block copolymers, thus are revolutionary techniques for polymer industry. Polymers with good control over molecular weight, molecular weight distribution, chain-end functionality and architectures can be prepared by these processes. In order to improve the existing applications and create new opportunities to design a new block copolymer system with improved physical and chemical properties, the combination of two different polymerization techniques have tremendous scope. Such kinds of macromolecules may be attended by combination of homopolymerization of different monomers by post-modification techniques using a macroinitiator or by using a dual initiator which allows the combination of two mechanistically distinct techniques. This review focuses on recent advances in synthesis of block copolymers by combination of living cationic polymerization with other polymerization techniques and click chemistry.

Enzyme-mediated radical initiation of acrylamide polymerization: main characteristics of molecular weight control

Polymer ◽  
2001 ◽  
Vol 42 (13) ◽  
pp. 5515-5521 ◽  
Author(s):  
Alain Durand ◽  
Thierry Lalot ◽  
Maryvonne Brigodiot ◽  
Ernest Maréchal
Keyword(s):  
Molecular Weight ◽  
Weight Control ◽  
Radical Initiation ◽  
Molecular Weight Control ◽  
Acrylamide Polymerization

Thermal Reorganization and Molecular Weight Control of Dynamic Covalent Polymers Containing Alkoxyamines in Their Main Chains

2007 ◽  
Vol 40 (5) ◽  
pp. 1429-1434 ◽  
Author(s):  
Hideyuki Otsuka ◽  
Koichiro Aotani ◽  
Yuji Higaki ◽  
Yoshifumi Amamoto ◽  
Atsushi Takahara
Keyword(s):  
Molecular Weight ◽  
Weight Control ◽  
Molecular Weight Control

New Alfin Rubbers

1970 ◽  
Vol 43 (2) ◽  
pp. 333-355 ◽  
Author(s):  
R. G. Newberg ◽  
H. Greenberg ◽  
T. Sato
Keyword(s):  
Molecular Weight ◽  
Laboratory Testing ◽  
Weight Control ◽  
Straight Chain ◽  
Cyclic Hydrocarbons ◽  
Molecular Weight Control ◽  
Heat Build Up ◽  
Polymerization Method ◽  
Butadiene Styrene

Abstract Molecular weight control for alfin catalyzed 1,3-diene polymers by 1,4-diene straight chain or cyclic hydrocarbons (and their derivatives) has been demonstrated. The microstructure of these moderated polymers is identical to the polymers obtained without molecular weight control. From the wide series of copolymers preparable with this improved polymerization method four were chosen for their evaluation after laboratory testing for processability, physicals, and economics. Copolymers of butadiene—isoprene (90/10 and 97/3) and butadiene—styrene (85/15 and 95/5) virgin or oil extended have been shown to be economically attractive and to give superior wear, traction, and adequate heat build up.

Kinetics and Molecular Weight Control of the Polymerization of Acrylamide via RAFT†

2004 ◽  
Vol 37 (24) ◽  
pp. 8941-8950 ◽  
Author(s):  
David B. Thomas ◽  
Anthony J. Convertine ◽  
Leslie J. Myrick ◽  
Charles W. Scales ◽  
Adam E. Smith ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Weight Control ◽  
Molecular Weight Control

Simultaneous Control of 1,4-cis Selectivity and Molecular Weight of Polymer in Polymerization of Butadiene with Co(acac)3/MAO Catalyst

2005 ◽  
Vol 78 (1) ◽  
pp. 143-154 ◽  
Author(s):  
Kiyoshi Endo ◽  
Naoyoshi Hatakeyama
Keyword(s):  
Molecular Weight ◽  
Reaction Time ◽  
Active Site ◽  
Weight Control ◽  
Catalyst Preparation ◽  
Polymerization Rate ◽  
Polymerization Time ◽  
Molecular Weights ◽  
Molecular Weight Control ◽  
Simultaneous Control

Abstract Simultaneous control of 1,4-cis selective polymerization and molecular weight of polymer in the polymerization of butadiene (BD) with Co(acac)3/MAO catalyst was investigated. The polymerization of BD with the Co(acac)3/MAO catalyst strongly depended on catalyst preparation, and the polymerization rate of BD with Co(acac)3 activated by MAO in the presence of BD was faster than that with previous reported results that the Co(acac)3 activated by MAO in the absence of BD. From a kinetic study, linear relation between ln[BD]0/[BD]t and polymerization time and no induction period for the polymerization were observed in the polymerization of BD with Co(acac)3 activated by MAO in the presence of BD. This indicates that the active site for the polymerization kept constant throughout polymerization. The molecular weights of the polymers increased linearly with polymer yields, and the line passed through the original point. The Mw/Mn of the polymers kept constant during reaction time. The polymerization of BD performed at 0 °C in the Co(acac)3/MAO catalyst gave high molecular weight 1,4-cis poly(BD) (1,4-cis content > 95) and narrow polydispersity (Mw/Mn=1.36). On the basis of these results, it is clear that simultaneous 1,4-cis selective and molecular weight control is possible in the polymerization of BD with the Co(acac)3/MAO catalyst.

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