• Textile Coloration and Finishing
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• v.33 no.2
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• pp.64-71
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• 2021

Large amount of formaldehyde could be released inevitably during the flame-retardant (FR) treatments or from the finished fabrics using Provatex reagent and Proban polymers which have been used as durable FRs for cotton. A water-soluble cyclophosphazene derivative was synthesized as an ecofriendly phosphorus-based FR for cotton fibers. Dichloro tetrakis{N-[3-(Dimethylamino)propyl]methacrylamido} cyclcophosphazene (DCTDCP) was synthesized through the substiutution reaction of Hexachloro cyclophosphazene and N-[3-(Dimethylamino)propyl] methacrylamide at a mole ratio of 1 : 4, which can be cured dually by both alkaline treatment and UV irradiation. More crosslinked networks were produced through the addition of Triacryloyl hexahydrotriazine and Acrylamide as a UV-curable crosslinker and a comonomer respectively. Both flame retardancy and washing durability of the FR cotton were improved synergistically. The durability improvement may be caused by the covalent bond formation of the FR with cellulose and the high degree of polymerization of DCTDCP, which can be verified by the pyrolysis and combustion behaviors analyzed by LOI, TGA, and microcalorimeter.

• The Journal of Natural Sciences
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• v.4
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• pp.95-102
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• 1991

The influences of various concentrations of thallium carbonate on the hydration of tricalcium silicate which is widely used to the inorganic materials have been studied using an isothermal microcalorime-ter. The experimental results indicate that the hydration of tricalcium silicate is accelerated in the presence of thallium carbonate, namely the concentration of thallium carbonate is increased, the rate of hydration is also increased. The x-ray diffraction analysis shows that the concentration of tricalcium silicate decreases rapidly in the presence of thallium carbonate. Differential thermal analysis of tricalcium silicate hydrated in the persence of thallium carbonate indicates the presence of calcium carbonate. The nonevaporable water content and the degree of hydration of tricalcium silicate show that the accelerating action of thallium carbonate is more pronounced only during the early period of hydration. Analytical results of the liquid phase in contact with the tricalcium silicate paste indicate that the concentrations of calcium and hydroxyl ions are changed considerably in the presence of thallium carbonate.

• Composites Research
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• v.35 no.6
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• pp.456-462
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• 2022

Since natural fibers are highly flammable, it is not easy to make them flame retardant. In this study, a liquid flame retardant based on phytic acid, APTES, and Thiourea, which are flame retardant candidates derived from nature, was prepared and its performance was verified through flame retardant treatment and flame retardancy evaluation of bamboo fibers. When a liquid flame retardant is used, it is possible to treat a large amount of natural fibers with flame retardant treatment. Nine types of flame-retardant treated bamboo fibers were prepared according to the Taguchi design of experiment method. Thereafter, vertical burning test and microcalorimeter test were performed for flame retardancy evaluation, and the surface of natural fibers before and after flame-retardant treatment was compared using scanning electron microscope. The results show that phytic acid has a significant effect on improving the flame retardancy of natural fibers. Through microstructure analysis, it was assumed that the phytic acid helps flame retardant to uniformly adhere to the surface of natural fibers. If such research results are utilized, it is possible to make a large amount of natural fibers high flammability in an eco-friendly way, which is expected to be advantageous for the application of prototypes.