SIGLEAvailable from British Library Document Supply Centre- DSC:DX184535 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Slark, A.T

Free-radical solution polymerization techniques have been used to
prepare carboxyl-terminated poly(methyl methacrylate) and poly(2-
ethyl hexyl acrylate) homopolymers. The molar masses of these
prepolymers were readily controlled and they were found to be
approximately monofunctional with respect to carboxy I groups.
These carboxyl-terminated prepolymers were converted to
methacrylate-terminated macromonomers via acyl chlorideterminated
intermediates. The macromonomer functionalities
obtained by this procedure were high, typically 0.90-1.05
methacrylate groups per molecule on average. The prepolymers and
macromonomers were characterized using End-group analysis (EGA).
Infra-red spectroscopy (IR), 1H Nuclear Magnetic Resonance
spectroscopy (lH NMR) and Gel-permeation Chromatography (GPC).
Polystyrene-graft-poly(methyl methacrylate) and
polystyrene-graft-poly(2-ethyl hexyl acrylate) copolymers were
prepared by the free-radical solution copolymerization of
macromonomers (M2) with styrene (M1). A dual detector GPC method
was used to estimate macromonomer conversions. Unreacted
macromonomer and styrene were removed and the purified graft
copolymers were characterized by Thin-layer Chromatography (TLC) ,
GPC, IR and 1H NMR. It was shown that efficient grafting had
occurred by copolymerization of the macromonomer end-group and
that ungrafted polystyrene backbone was not produced. The graft
copolymer chemical compositions and physical architectures were
controlled by changing the comonomer feed composition or the
macromonomer molar mass. Reactivity ratios (r1) were determined
by the Jaacks, Finnemann-Ross and Kelen-TUdos methods. It was
shown that the reactivities of the methacrylate-terminated
macromonomers were approximately similar to conventional
methacrylates and independent of the macromonomer molar mass or
composition within the limits investigated. The polystyrene-graft-poly(2-ethyl hexyl acrylate) copolymers
have been used as stabilizers in the free-radical non-aqueous
dispersion polymerization of methyl methacrylate in aliphatic
hydrocarbons. The poly(methyl methacrylate) particles were
characterized by Transmission Electron Microscopy (TEM) in order
to determine their size, shape and state of aggregation. Ultraviolet
spectroscopy (UV) was used to determine the graft
copolymer content of the particles, from which an estimate of
surface coverage was made. The effects of varying the
polymerization method, and both the composition and concentration
of stabilizers used, were studied. The average particle size,
particle size distribution and the state of aggregation were
found to be dependent upon these parameters

Andrew T. Slark (2313790)

Loughborough University Institutional Repository

English

Graft copolymer stabilizers for non-aqueous polymer dispersions

OpenGrey Repository

https://repository.lboro.ac.uk/articles/Graft_copolymer_stabilizers_for_non-aqueous_polymer_dispersions/9397664/files/17012936.pdf

Graft copolymer stabilizers for non-aqueous polymer dispersions

Abstract

Similar works

Full text

Available Versions

Loughborough University Institutional Repository

OpenGrey Repository