Design, synthesis and physical properties of poly(styrene-butadiene-styrene)/poly(thiourea-azo-sulfone) blends

Abstract

A new aromatic azo-polymer, poly(thiourea-azo-sulfone), has been synthesized using 1-(4thiocarbamoylaminophenylsulfonylphenyl)thiourea and diazonium salt solution. Conducting and thermally stable rubbery blends of poly(styrene-block-butadiene-block-styrene) (SBS) triblock copolymer and poly(thiourea-azo-sulfone) (PTAS) were produced by solution blending technique. PTAS possessed fine solubility in polar solvents and high molar mass 63 × 10 3 g moL −1. Microscopic analysis on SBS/PTAS blends revealed good adhesion between the two polymers without macro phase separation. Electrical conductivity measurement recommended that blending of SBS with 60% PTAS was sufficiently conducting 1⋅43 S cm-1. A relationship between PTAS loading and thermal stability of blends was observed. With the increasing PTAS content, 10% gravimetric loss was increased from 481 to 497 °C, while glass transition improved from 123 to 136 °C (better than neat SBS but lower than PTAS). The blends also established higher tensile strength (52⋅40-59⋅96 MPa) relative to SBS. Fine balance of properties renders new SBS/PTAS, potential engineering plastics for a number of aerospace relevance.

Structure and design of polymers for durable, stretchable organic electronics

“…131 The single phase morphology of the PTAS (13) and SBS film was confirmed by SEM. Though the conductivity of PTAS (13) decreased from 2.42 S cm − 1 to 0.065-1.43 S cm − 1 in the blends, the mechanical properties improved with higher PTAS (13) content, contrary to phase-segregated blends.…”

“…This can be explained by the morphology of these usually immiscible blends; larger domains of conjugated polymer improve electrical properties but introduce more of its brittle character as its concentration increases. 125,130,131 An example is illustrated in Figure 15, where larger phases of conducting polymer and higher miscibility between polymers showed increased conductivity. 129 To maintain conductivity without greatly changing the mechanical properties of the rubber, low percolation thresholds of conjugated polymers are desirable.…”

Enhanced miscibility and strain resistance of blended elastomer/π‐conjugated polymer composites through side chain functionalization towards stretchable electronics

“…One approach to produce stretchable conductive materials takes advantage of the inherent properties of π‐conjugated polymers and elastomers through polymer blending . Insulating elastomers can tolerate and recover from high repeated strain.…”

“…Some studies suggest that greater miscibility can reduce the mechanical/electrical property tradeoff, yet elastomer/π‐conjugated polymer blends are typically phase segregated . Enhanced compatibility for traditional insulating polymers can be achieved by improving interfacial adhesion through stronger intermolecular interactions, reactive bonding between polymers or tailored compatibilizing additives .…”

“…11 One approach to produce stretchable conductive materials takes advantage of the inherent properties of -conjugated polymers and elastomers through polymer blending. [12][13][14][15][16][17][18][19][20][21][22][23][24][25] Insulating elastomers can tolerate and recover from high repeated strain. On the other hand, -conjugated polymers are brittle due to the rigid, planar backbones and -interactions that generate charge transport.…”