Search results for "polymerization"

Polymerization of Triazolinediones withtrans-3,3-Dichloro-1-phenyl-1-propene

1997

The reaction of 4-phenyl-1,2,4-triazoline-3,5-dione (PhTD) (2) with trans-3,3-dichloro-1-phenyl-1-propene (4) was investigated at room and reflux temperatures in methylene chloride solution. Although the reaction is slow, it gives quantitative yield. This reaction leads to the formation of two 2:1 adducts via double Diels–Alder and Diels–Alder-Ene reactions in a ratio of about 1: 7. The major product was isolated by means of fractional crystallization as a pure compound and was characterized by infra-red (IR), 1H nuclear magnetic resonance (NMR), 13C NMR, mass spectra and elemental analysis. The structure of the minor product was determined by IR and 1H NMR. These compounds were used as mod…

Graft Copolymers with Complex Polyether Structures: Poly(ethylene oxide)-graft-Poly(isobutyl vinyl ether) by Combination of Living Anionic and Photoi…

2014

Hydroxyfunctional oxetane-inimers with varied polarity for the synthesis of hyperbranched polyether polyols via cationic ROP

2014

Novel initiating systems for the living polymerization of acrylates and methacrylates

1998

The polymerization of methyl methacrylate with lithiated initiators in the presence of aluminium alkyls in toluene has living character but it deviates from conventional first-order kinetics and the polymers have fairly broad molecular weight distributions. This results from the formation and precipitation of a coordinative polymer network in which the lithium ions of the living chain ends are coordinated to the in-chain ester carbonyl groups. Thus, the network formation can be prevented by adding Lewis bases like methyl pivalate which coordinate to the living chain ends instead ofthe polymer. Alternatively, one can introduce tetraalkylammonium salts aiming at an exchange of the lithium ion…

Influence of End Groups on the Stimulus-Responsive Behavior of Poly[oligo(ethylene glycol) methacrylate] in Water

2010

The influence of the chemical structure of both end groups onto the lower critical solution temperature (LCST) of poly[oligo(ethylene glycol) monomethyl ether methacrylate] (POEGMA) in water was systematically investigated. POEGMA of Mn = 3550 g/mol and Mw/Mn = 1.14 prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization was equipped with two different functional end groups in a one-step postpolymerization reaction combining activated esters, functional amines, and functional methane thiosulfonates. As end groups, n-propyl, n-hexadecyl, di(n-octadecyl), poly(ethylene glycol)-550 (PEG), 1H,1H-perfluorononyl, azobenzene, and trimethylethylammonium groups were system…

Syndiospecific polymerization of styrene using methylaluminoxane-activated bis(phenolato)titanium complexes

1998

Styrene was polymerized using a series of methylaluminoxane-activated bis(phenolato)titanium complexes of the type ((OC 6 H 2 -4-Me-6- 1 Bu) 2 Z)TiX 2 (X = Cl, O 1 Pr, η 5 -C 5 Me 5 ) to give syndiotactic polystyrene. Catalyst activity was found to depend on the nature of the bridging group Z, where Z = CH 2 , CH 2 CH 2 , S, S=O. Activity was found to be highest for Z = S.

RAFT Synthesis of Reactive Multifunctional Triblock‐Copolymers for Polyplex Formation

2021

Poly(phosphonate)s via Olefin Metathesis: Adjusting Hydrophobicity and Morphology

2014

Olefin metathesis step-growth (acyclic diene metathesis (ADMET)) and chain-growth (ring-opening metathesis) polymerization was used to prepare linear poly(phosphonate)s with variable hydrophilicity. The first phosphonate monomer, i.e., di(undec-10-en-1-yl) methylphosphonate, for ADMET polymerization was developed, and potentially degradable and biocompatible, unsaturated poly(phosphonate)s were prepared with molecular weights up to 23 000 g mol–1 with molecular weight dispersities Đ < 2. These polymers were studied with respect to their interaction with a calcium phosphate bone substitute material from an aqueous nanoparticle dispersion that was prepared by a solvent evaporation miniemulsio…

Polyether Core-Shell Cylinder-Polymerization of Polyglycidol Macromonomers

2005

The synthesis and polymerization of macromonomers containing a polymerizable styrene head group and a tail of ethylene oxide derivatives of different character were investigated. The synthesis of macromonomers was based on living anionic polymerization of oxiranes. Two monomers were used: 1-ethoxyethyl glycidyl ether (glycidol acetal), which after hydrolysis forms hydrophilic glycidol blocks and glycidyl phenyl ether forming hydrophobic blocks. Polymerizable double bonds were introduced by terminating the living chain with p-(chloromethyl)styrene. The radical polymerization of the macromonomers was carried out in water with addition of a non-polar solvent (benzene) and AIBN as initiator. Co…

Pyrene Containing Polymers for the Non-Covalent Functionalization of Carbon Nanotubes

2009

Pyrene containing diblock copolymers based on poly(methyl methacrylate) were synthesized and investigated regarding their adsorption on carbon nanotubes (CNT). The pyrene units were introduced using a reactive ester monomer for the build up of the second block which later on was reacted polymer-analogously with amine functionalized pyrene derivatives. As we started from the same reactive ester intermediate, full block length identity is given. We varied the length of the anchor block to find an optimal block length and used pyren-1-yl-methylamine as well as 4-pyren-1-yl-butylamine as anchor units. For both anchor units a maximal adsorption was found for 13 and 20 anchor units, respectively.…