Acrylate based core – shell microspheres

Description

Polymeric microspheres with a core – shell structur e, in contrast to microcapsules, are by definition small spheres which have no distinct outer layer or membr ane and are therefore susceptible for diffusion phenomena 1 . This leads to a wide variety of fields of applica tion, such as in the food industry or in the medical field as drug delivery system 2-4 . When the core of such a sphere is a comprised of a volatile substance, the sphere becomes expandable upon reach ing the shells glass transition temperature and the core substances boiling point. This has been used i n industry since the 1970s for different purposes s uch as coating agents, in adhesive applications or thermal insulation enhancement 5 . This work is focused on the synthesis of microspher es with a core-shell structure, whereas the core is an inert carbohydrate and the shell is acrylate based. The reactions are carried out as oil in water (OIW ) suspensions and as free radical polymerisations. Se veral different monomers (acrylonitrile, methyl methacrylate, acrylic acid, dipropylene glycol diac rylat and vinyl acetate) and initiators (AIBN and D LPO) are used. Through the variation of the monomer ratios, initiator variation and the OIW ratio, different sh ell composition can be observed. The characterization c onducted with differential scanning calorimeter rev eals as expected different glass transition temperatures and melting points for the shell. Scanning electro n microscopy is used to characterize the shape and si ze of the microspheres.

Period	22 Jun 2016
Event title	Polymat Spotlight 2016
Event type	Conference
Location	SpainShow on map