The Modification of Butadiene-Acrylonitrile Rubber with Vinylcyclohexyl Ketone

Abstract Butadiene-acrylonitrile-vinylcyclohexyl ketone (BD-AN-VCHK) terpolymer was synthesized by radical polymerization. The structure of the synthesized terpolymer was elucidated by IR spectroscopy and physical and mechanical tests. BD-AN-VCHK terpolymer was stable at lower temperatures and exhibited good adhesive properties. It was also observed that the yield of terpolymer was dependent upon the initial concentration of VCHK and pH of the media. The percentage of conversion increased by increasing the initial concentration of VCHK. With addition of 10.8% VCHK to the BD-AN mixture, the glass transition temperature (Tg) value of the polymers decreased from −40 °C to −57 °C. However further increase of VCHK ratio (20.4%) resulted in the formation of the polymers with Tg value of −48 °C. It was shown that this was due to the fact that VCHK, entering the structure during polymerization process, converted the trans structure of butadiene sequences into the cis form.

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Where is the glass transition temperature of poly(tetrafluoroethylene)? A new approach by dynamic rheometry and mechanical tests

European Polymer Journal ◽

10.1016/j.eurpolymj.2013.04.028 ◽

2013 ◽

Vol 49 (8) ◽

pp. 2214-2222 ◽

Cited By ~ 45

Author(s):

Gérard Calleja ◽

Alex Jourdan ◽

Bruno Ameduri ◽

Jean-Pierre Habas

Keyword(s):

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Mechanical Tests ◽

New Approach ◽

Dynamic Rheometry

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Improving Thermal Performance of High Internal Phase Emulsion Polymerized Foams with Maleimide Based Monomers

MRS Proceedings ◽

10.1557/proc-431-539 ◽

1996 ◽

Vol 431 ◽

Cited By ~ 3

Author(s):

Mark A. Hoisington ◽

Joseph R. Duke ◽

David A. Langlois

Keyword(s):

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Thermal Performance ◽

Foam Glass ◽

Polymerization Process ◽

High Internal Phase Emulsion ◽

Internal Phase

AbstractThe influence of three N-substituted maleimides on the thermal performance of high internal phase emulsion (HIPE) polymerized foams were investigated. N-propylmaleimide, Nbutylmaleimide, and N-cyclohexylmaleimide were copolymerized with styrene and crosslinked with either divinylbenzene or Bis(3-ethyl-5-methyl-4-maleimide-phenyl)methane in a HIPE polymerization process. All maleimide modifiers produced increases in the foam glass transition temperature (Tg) as a function of the maleimide concentration. The degree of Tg improvement was strongly dependent on the N-substituted maleimide used during processing.

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Titanium and Vanadium Catalysts with 2-Hydroxyphenyloxazoline and Oxazine Ligands for Ethylene-Norbornene (co)Polymerization

Catalysts ◽

10.3390/catal9121041 ◽

2019 ◽

Vol 9 (12) ◽

pp. 1041

Author(s):

Wioletta Ochędzan-Siodłak ◽

Dawid Siodłak ◽

Aleksandra Piontek ◽

Karel Doležal

Keyword(s):

Molecular Weight ◽

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Molecular Weight Distribution ◽

Weight Distribution ◽

Vanadium Complexes ◽

Crystallinity Degree ◽

Initial Concentration ◽

Highly Active

A series of titanium and vanadium complexes with oxazoline 2-(4,5-dihydro-1,3-oxazol-2-yl)phenol (L1), 2-(4-methyl-4,5-dihydro-1,3-oxazol-2-yl)phenol (L2), and oxazine 2-(5,6-dihydro-4H-1,3-oxazin-2-yl)phenol (L3) ligands were synthesized, and their structures were determined by NMR and MS methods as (L)2MtCl2. The vanadium complexes were found to be highly active in ethylene (7300 kgPE/(molV·h)) and ethylene/norbornene (5300 kgCop/(molV·h)) (co)polymerization. The polyethylene characteristics were melting temperature (123–142 °C), crystallinity degree (49–75%), molecular weight (5.7–8.5 × 105 g/mol), molecular weight distribution (1.5–2.4). The ethylene-norbornene (E-NB) copolymer characteristics were molecular weight (2.6–0.9 × 105 g/mol), molecular weight distribution (1.6–2.2), glass transition temperature (4–62 °C), norbornene incorporation (12.3–30.1 mol%) at initial concentration (0.5–1.5 mol/L). The microstructure of E-NB copolymers depends on the catalyst applied with the highest diads content for the (L3)2VCl2 and triads for the (L2)2VCl2 complexes.

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