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Volume 8, Issue 6 (Suppl)
J Bioremediat Biodegrad, an open access journal
ISSN:2155-6199
Biopolymers & Bioplastics 2017
October 19-20, 2017
October 19-20, 2017 San Francisco, USA
7
th
International Conference and Exhibition on
Biopolymers and Bioplastics
The effect of feeding profile in the distribution of chains composition and mechanical performance of
styrene/butyl acrylate emulsion copolymers
Alvaro H Arnez
IFEO, Bolivia
S
emicontinuous seeded emulsion copolymerizations, using 5 different types of feeding profiles of comonomers (styrene/butyl
acrylate, S/BA) were carried out, to vary in a gradual manner the composition of the copolymer chains formed throughout the
reactions (gradient composition copolymer, GCC). For comparison, equivalent core-shell type polymeric materials were synthesized
in two stages (TS). In all reactions, the S/BA global mass ratio was: 70/30. To estimate the weight composition distribution (WCD)
of the copolymer chains, the cumulative styrene content in the polymer mass was followed throughout the reaction (1H-NMR).
Average molecular weights were determined using SEC. The differences in mechanical performance were established, carrying out
a mechanodynamic (DMA), and mechanostatic characterization (stress-strain at several temperatures and, Izod testing). The area
under the loss modulus curve (LA) was correlated with Izod impact strength, showing the damping superiority of the GCCs over
the T-S material. At all tested temperatures (between 25 and 70°C), the GCC materials exhibited yielding and plastic deformation,
while the T-S material presented brittle fracture in that temperature interval. The WCDs were used to elucidate the differences in
mechanical behaviour among GCC materials. The feeding profile variation in combination with the WCD analysis represents a novel
methodology to produce tailor made copolymers.
alvaro.arnez@gmail.comJ Bioremediat Biodegrad 2017, 8:6 (Suppl)
DOI: 10.4172/2155-6199-C1-012