Polyethylene glycol grafted cotton as phase change polymer

Thermal storage cotton possessing solid–solid phase change properties was prepared by direct grafting of polyethylene glycol (PEG) on cotton fiber/cloth. Attempt has been made to characterize intermediates so that desired grafting could be obtained. The grafting was done by using urethane linkage and the grafted cotton was found to undergo solid–solid phase transition. The modified cotton was characterized by using Fourier transform infrared spectroscopy (FT-IR), ¹³C CPMAS, polarizing optical microscopy, differential scanning calorimetry (DSC) and thermogravimetry respectively. The DSC study revealed quite good storage effect of grafted cotton and the enthalpy of melting was found to be 55–59 J/g with a peak appearing at around 60 °C. During cooling scan, the crystallization peak appeared at around 38 °C. Further, thermogravimetric analysis confirmed good thermal stability up to 300 °C. Appreciable improvement of mechanical properties of cotton has been observed after grafting. The polarizing optical micrograph clearly showed change of morphology after grafting, i.e., the grafted PEG adhering to fiber surface.