Synthesis and Characterization of High Performance Interpenetrating Polymer Networks With Polyurethane and Poly(methyl methacrylate)

J of Applied Polymer Sci

Thorne

Auad

et al. 2021

Self Cite

In this study, a carbon fiber/vinyl ester‐polyurethane interpenetrating polymer network (IPN) laminate composite was fabricated and characterized for the first time. The IPN matrix, consisting of a commercially available vinyl ester and polyurethane, was synthesized via a sequential method with vinyl ester as the rigid phase and polyurethane as the flexible phase. Good compatibility between the two phases in the matrix was achieved and confirmed via differential scanning calorimetry and dynamic mechanical analysis. The thermomechanical response of the IPN matrix was compared with that of an unmodified vinyl ester resin. The presence of the more ductile polyurethane in the IPN matrix depressed the glass transition temperature (from 94 to 84°C), but also served to improve damping response at all frequencies studied. Tensile and flexural tests were performed on the carbon fiber/IPN and carbon fiber/vinyl ester composites to determine their mechanical response. The IPN composite exhibited lower tensile properties than the vinyl ester composite. However, its flexural properties were on par with those of the vinyl ester composite.

Section: Resultsmentioning

confidence: 80%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Mechanical performance of vinyl ester—polyurethane interpenetrating polymer network composites

J of Applied Polymer Sci

Thorne

Auad

et al. 2021

Self Cite

“…The enhancement in phase compatibility of the IPNs was also addressed. 6,25,[28][29][30][31][32][33] In the work reported here, the impact of varying the acrylic copolymer precursors and the chemical bonding between the two polymer networks was investigated towards the overall goal of synthesizing novel graft-IPNs with excellent compatibility, transparency and superior fracture toughness. For the first time, styrene, as one of the acrylic copolymer monomers, was utilized in the graft-IPN system.…”

Section: Introductionmentioning

confidence: 99%

High‐fracture‐toughness acrylic–polyurethane‐based graft‐interpenetrating polymer networks for transparent applications

Barde

Minkler

et al. 2020

Polymer International

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Transparent materials with robust mechanical properties are essential for numerous applications and require careful manipulation of polymer chemistry. Here, polyurethane (PU) and acrylic-based copolymers out of styrene were utilized to synthesize transparent PU-acrylic graft-interpenetrating polymer networks (graft-IPNs) for the first time. In these materials, PU imparts greater flexibility, while the acrylic copolymer increases rigidity and glass transition temperature of the graft-IPNs. Kinetics of the graft-IPN synthesis was monitored using Fourier transform infrared spectroscopy and 1 H NMR spectroscopy through the conversion of the isocyanate group. System compatibility, degree of phase separation and material transparency were evaluated using transmission electron microscopy and UV-visible spectroscopy. Overall, higher compatibility is observed at a higher percentage of styrene in the acrylate copolymer. The thermomechanical properties of the IPNs were quantified using dynamic mechanical analysis to assess the effect of the acrylic copolymer content on fracture toughness of the resulting graft-IPNs. The high fracture toughness of the graft-IPNs, coupled with excellent transparency, demonstrates the potential of these systems for high-performance applications.

Mechanical characterization and modeling stress relaxation behavior of acrylic–polyurethane‐based graft‐interpenetrating polymer networks

Polymer Engineering & Sci

Celestine

Auad

et al. 2021

Self Cite

The stress relaxation behavior of acrylic-polyurethane (PU)-based graftinterpenetrating polymer networks (IPNs) was characterized via dynamic mechanical analysis (DMA) and modeled using finite element method (FEM) analysis. Stress relaxation of glassy IPN specimens was experimentally studied under flexural testing, while rubbery IPN specimens were tested in tension. The effects of varying the styrene content in the acrylic copolymer phase, compatibility of the two phases in IPNs, and changing the concentration of acrylic copolymer and PU were studied. A higher percentage of styrene content resulted in higher homogeneity of IPN specimens, and decrease in initial modulus for acrylic copolymer specimens. Additionally, glassy IPN specimens with 90% styrene shows resistance to relaxation as high as acrylic copolymer samples. Experimental results were used to develop a numerical model to study stress relaxation response of specimens. While polymer systems have been