نوع مقاله : پژوهشی
نویسندگان
دانشگاه صنعتی امیرکبیر
عنوان مقاله [English]
نویسندگان [English]
W
ater born poly(styrene-butyl acrylate)/clay nanocomposite latexes were
synthesized by a novel initiating system of activators generated by
electron transfer (AGET) in a system of atom transfer radical polymerization
(ATRP). Initially, the clay was swelled in a mixture of styrene, butyl acrylate,
and hexadecane. The mixture was then sonicated to obtain a stable miniemulsion. To
synthesize poly(styrene-butyl acrylate)/clay nanocomposite latexes, the reducing
agent (ascorbic acid) was added dropwise to the reactor (to reduce termination reactions).
Particle size and particle size distribution of resulting nanocomposite latexes
were determined by dynamic light scattering (DLS). These latex particles were produced
with diameters in the size range of 138-171 nm. In addition, the increase in
clay content led to increased particles size. Number and weight-average molecular
weights of the resultant copolymer nanocomposites and their molecular weight distributions
were determined by gel permeation chromatography. The narrow molecular
weight distribution of the nanocomposites is an indication of a successful ATRP
which was accomplished in miniemulsion formation. Using
1
H NMR, copolymers
were characterized and the mol ratios of monomers in copolymer composition were
calculated. X-Ray diffraction and transmission electron microscopy results showed
the mixed intercalated and exfoliated morphologies of nanocomposites in which
homogeneous distributions of clay layers in the polymer matrix have been achieved.
کلیدواژهها [English]