Study of castor oil polyurethane - poly(methyl methacrylate) semi-interpenetrating polymer network (SIPN) reaction parameters using a 2³ factorial experimental design

Abstract

In this work was employed a 2 3 factorial experiment design to evaluate the castor oil polyurethane-poly(methyl methacrylate) semi-IPN synthesis. The reaction parameters used as independent variables were NCO/OH molar ratio, polyurethane polymerization time and methyl methacrylate (MMA) content. The semi-IPNs were cured over 28 h using two thermal treatments. The polymers were characterized by infrared and Raman spectroscopy, thermal analysis and swelling profiles in n-hexane. The glass transition temperature (Tg) and the swelling were more affect by the NCO/OH molar ratio variation. The semi-IPNs showed Tg from -27 to -6 °C and the swelling range was from 3 to 22%, according to the crosslink density. The IPN mechanical properties were dependent on the cure temperature and MMA content in it. Lower elastic modulus values were observed in IPNs cured at room temperature.

The Influence of an Isocyanate Structure on a Polyurethane Delivery System for 2′-Deoxycytidine-5′-monophosphate

“…Raman spectroscopy was also used to assess the chemical structures of products and possible interactions. The complete reaction of isocyanate groups can be assumed by the presence of the -C-N-single bond axial stretch (between 1518-1550 cm −1 ), because the specific peak of -NCO groups does not appear in the observed range [66].…”

Castor oil as a renewable resource for the chemical industry

“…The corresponding IPN exhibited Young's moduli in the order of 2.9-84 mN/m 2 and degradation temperatures in the range of 525-535 7C. Cunha et al [154] employed a statistical method to accurately evaluate the properties of castor oil-based semi-IPN. They used a 2 3 factorial experimental design for the optimization of the properties of these materials.…”

Hydrolytic stability and biocompatibility on smooth muscle cells of polyethylene glycol–polycaprolactone-based polyurethanes

“…Furthermore, a peak at 2270 cm -1 corresponding to the isocyanate group was absent, suggesting the complete reaction for urethane bond formation 17 . DOI: 10.1557/jmr.2020.303 The region between 850 and 1111 cm -1 can be assigned to the skeleton of PCL; some authors attribute those peaks to interactions of C-C stretch, C-O stretch, and C-COO stretch, which are characteristic of polyesters 18,19 .…”