Star-block copolymer copolymers Baroplastic

Figure 3. Images of a) the mold with starting and processed polymers, b) processed baroplastic(PEHAo.4g-b-PSo,3i)" 4-arm star-block copolymer (P6), at different pressures for 1 min at room temperature.

Herein, in addition to the existing baroplastics, we have shown that baroplastic tri- and star-block copolymers can be recycled multiple times. For example, recycling of P6 (Figure 8) was achieved by chopping and remolding at 400 kg cm for 30 min which was repeated five times. The fact that the resulting material is still remoldable is an indication of the recyclability of the material. 

It was also shown that baroplastic materials can be used as a processing aid to process high Tg homopolymer such as polystyrene (PS). To optimize the conditions, polystyrene and baroplastic materials in powder form were blended at different compositions and pressed using compression or extrading at room temperature. The results indicate that a room temperature moldable polystyrene/baroplastic blend can be obtained at 50 wt% baroplastic content with the di-block, tri-block and star-block copolymers. Figure 10 shows that the 50 wt% blend of PS (45K) and 4-arm star-block copolymer (98K, P8) can be... 

Figure 10. Images of processed PS homopolymer and baroplastic (PSo.5o-b-PEHAo.5() Farm star-block copolymer (P8) blend.

Several di-, tri- and star-block copolymers with assorted compositions and molecular weights were synthesized by ATRP. The block copolymers obtained have shovm baroplastic behavior by simple compression and/or extruding at room temperature. 

Baroplastic di-, tri- and star-block copolymers were shown to act as processing aids in the processing of homo-polystyrene. Detailed studies with different baroplastic materials as processing aids and the mechanical properties of the obtained materials are under investigation. 

In this study, well-defined PS-6-PEHA di-block, PS-6-PEHA-6-PS and PEHA-6-PS-6-PEHA tri-block, (PS-6-PEHA) 3-arm star-block, (PEHA-6-PS)" and (PS-6-PEHA) 4-arm star-block copolymers were synthesized via ATRP. In order to compare the effect of structures on the baroplastic behavior, some block copolymers were obtained with the replacement of iimer/outer soft segments. Herein, some of the obtained block copolymers and their... 

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