Vinyl trimethoxysilane grafting reactions of low-density polyethylene (LDPE) were performed in an extruder, followed by crosslinking with boiled water. The thermal properties of both silane-grafted and silane-grafted water-crosslinked LDPE were investigated using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). DSC data showed that the silane grafts on the LDPE molecules were thermal stable in the absence of moisture under 130°C under which the silane-grafted LDPE could be processed or recycled. The silane grafts on the LDPE molecules reduced the melting point of LDPE and gave rise to an endotherm shoulder at about 85°C. TGA data showed that the decomposition temperature of the silane-grafted LDPE was much higher than that of LDPE. It was demonstrated that the cause of the increase in the decomposition temperature was not due to the silane grafts but due to the peroxideinduced crosslinking reactions during the silane grafting reactions performed in an extruder. Silane-grafted water-crosslinked LDPE displayed multiple melting behavior resulting from phase separation during crosslinking of LDPE with water. The phase separation gave rise to two melting points, including one at about 94°C, and the other at about 107°C.

ABSTRACT:In this experiment, cotton fabrics were treated by padding, drying, and curing with an antiwrinkle finishing reagent, dimethylolethylene urea (DMEU), in combination with different concentrations of tetraethoxysilane (TEOS) and isopropanol (IPA) at various volumes. The treated fabrics were studied to determine the effects of adding TEOS and IPA. They were also analyzed using Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) methods to examine the binding between SiO 2 and DMEU. The results showed that hydrogen bonds formed between SiO 2 and DMEU. TEOS was found to improve the antiwrinkle properties, tensile strength retention, and yellowing of the treated fabrics, although their softness was slightly reduced. The solvent IPA was shown to decrease the tensile strength of treated fabrics, although it improved their antiwrinkle properties. We observed only one stage of pyrolysis in untreated cotton fabrics, whereas the treated fabrics showed two stages. In addition, the fabrics treated with TEOS showed improved heat resistance. Our findings demonstrated that cotton fabrics showed excellent antiwrinkle properties and high tensile strength, when treated with a finishing solution composed of DMEU, 3% TEOS, IPA and water, followed by predrying and curing.