Impact of ambient and vacuum pressure on the physico mechanical properties of flexible polyurethane foam reinforced withCaCO₃

Abstract

This study investigates the effects of variable pressure conditions (550 and 1013 mbar) on the physico‐mechanical and structural properties of flexible polyurethane foam, incorporating different compositions of calcium carbonate (CaCO3) filler. The objective is to achieve sustained mechanical and structural properties of flexible polyurethane foam while reducing costs through variable pressure foaming technology. With CaCO3 filler concentrations ranging from 20 to 100 parts per hundred (pphp) of polyol, it was found that foam produced at low pressure (550 mbar) demonstrated improved resilience and durability, particularly with CaCO3 compositions up to 100 pphp. Conversely, foam produced at standard atmospheric pressure (1013 mbar) using compositions up to 100 pphp did not exhibit significant enhancements in physico‐mechanical properties. The study employs various characterization techniques, including mechanical testing, scanning electron microscopy, differential scanning calorimetry, thermal gravimetric analysis, and Fourier transform infrared spectroscopic analysis, to assess the flexible polyurethane foam. It provides a detailed examination of the effects of variable pressure on cellular structure, cell size, filler distributions, mechanical properties, and thermal stability of flexible polyurethane foam using CaCO3 filler.