Semi‐interpenetrating polymer networks composed of poly(ethylene terephthalate) and vernonia oil

Abstract

SYNOPSISSemi-interpenetrating networks have been synthesized from vernonia oil-sebacic acid polyester network and poly (ethylene terephthalate) ( P E T ) . Bond interchange reactions during mixing of the two materials led to the formation of a miscible copolymer mixture, in which the vernonia oil was then cross-linked with sebacic acid. The materials were phase-separated, exhibiting two glass transitions, when the network was synthesized at 160°C, below the crystallization temperature of PET; however, a single stable glass transition ( T,) results after the material is heated to above the melting temperature of PET and cooled. When the vernonia polyester network was completely formed at 250°C, above the crystallization temperature of PET, noncrystalline, single-T, material was created. The two-phase semi-IPNs were much tougher than were their constituent materials, with the 50% semi-IPN over 15 times tougher than the PET from which it was made and over 50 times tougher than the neat vernonia oil elastomer, with tensile energy to break of 1780 kJ/m3. The single-T, material was nearly 2.5 times as tough as the two-phase material, with energy to break of 4400 kJ/m3. The microstructure of the two-phase 50% semi-IPN was investigated by transmission electron microscopy, which showed regularly shaped spherulites of 10-20 pm in diameter, as compared to irregularly shaped spherulites observed in a similar 50/50 castor oil urethane/PET semi-IPN, in which the network formed simultaneously with PET crystallization. Scanning electron microscopy of the semi-IPN fracture surfaces showed microscopic fibrils several hundred nanometers in diameter in both the two-phase and single-T, materials, although only the two-phase semi-IPN had a macroscopically rough surface.

Photomechanical Switching Behavior of Semi‐Interpenetrating Polymer Network Consisting of Azobenzene‐Carrying Crosslinked Poly(vinyl ether) and Polycarbonate

“…The obtained structure is called a ''semi-IPN'' and is of great interest because it is easy to prepare and process owing to the soluble and thermoplastic nature of the linear polymer matrix. [6][7][8][9] Herein, we report on a new binary polymer system with a semi-IPN structure that has been designed to function as a Summary: A novel semi-interpenetrating polymer network (semi-IPN) with photomechanical switching ability was developed by a cationic copolymerization of azobenzenecontaining vinyl ethers in a matrix of a linear polycarbonate (PC). The semi-IPN film showed reversible deformation upon switching the UV irradiation on and off and responded with unprecedented rapidity.…”

Interpenetrating polymers networks derived from silylated soybean oil and water soluble polysiloxanes

“…Thus, IPNs of polyacrylates with castor oil or polyesters with castor oil were prepared and were shown to have better mechanical and physical properties than the individual components . In addition to castor oil, other functionalized oils (vernonia oil, lesquerella oil, crambe oil, and linseed oil) were also used in IPNs with polystyrene and polyacrylics . Most of the previous IPN work with triglycerides involved preparing a homogeneous solution of the triglycerides with specific monomers, then polymerizing and crosslinking it as the phase separation occurred.…”

Biobased interpenetrating polymers networks derived from oligomerized soybean oil and polydimethylsiloxane

“…Several examples of castor oil IPNs with acrylates or polyesters have also been reported and these IPNs showed better mechanical and physical properties than the individual components . Other IPNs have been prepared from functionalized vernonia oil, lesquerella oil, crambe oil, and linseed oil (as well as their epoxidized derivatives) with polystyrene and polyacrylics . Most of the previous IPN work with triglycerides involved preparing a homogeneous solution of the triglycerides with the desired monomer, then polymerizing and crosslinking as phase separation occurred.…”