Development of Kapok/Recycled-PET Blended Needle-Punched Thermal Waddings

Kapok fiber is emerging as a cheaper natural fiber having excellent thermal insulation properties. Recycled polyester/kapok blended needle punched nonwoven waddings are prepared where the effect of kapok fiber %, sheet areal density, and needle punch density on thermal resistance and air permeability is measured and analyzed with the help of MINITAB®18.1. Three percentages of kapok fiber (20, 40, 60%), four levels of fabric areal density (150, 300, 450, 600 g.m-2) and two levels of punch density (15, 20 punches.cm-2) were chosen. The statistical analysis revealed that kapok fiber % and areal density had a significant effect on both thermal resistance and air permeability of nonwovens. The thermal resistance was decreased significantly with the increase in kapok fiber %, especially at higher punch density. A significant interaction between kapok fiber % and areal density was observed for air permeability. It may be concluded that, in the selected range of input variables, recycled PET/kapok nonwovens with less % of kapok fibers and punch density display better thermal insulation performance, especially at higher areal density. The prepared nonwovens may find applications in winter coats and wadding layers for quilts, etc., and will also help to reduce the pollution from the environment.