	US 11,982,020 B2
	Method for production of poly-vinyl alcohol-filament fibre of high strength and elasticity
Mehmet Kivanç Alay, Denizli (TR); and Mustafa Soylu, Denizli (TR)
Appl. No. 17/424,114
Filed by Veritas Tekstil Konfeksiyon Pazarlama Sanayi Ve Ticaret Anonim Sirketi, Denizli (TR)
PCT Filed Jul. 1, 2020, PCT No. PCT/TR2020/050565 § 371(c)(1), (2) Date Jul. 19, 2021, PCT Pub. No. WO2021/002820, PCT Pub. Date Jan. 7, 2021.
Claims priority of application No. 2019/09816 (TR), filed on Jul. 1, 2019.
Prior Publication US 2022/0064822 A1, Mar. 3, 2022
Int. Cl. D01F 6/14 (2006.01); D01D 5/06 (2006.01); D01F 13/04 (2006.01)

CPC D01F 6/14 (2013.01) [D01D 5/06 (2013.01); D01F 13/04 (2013.01)]

11 Claims

1. A method of fiber production comprising:

filtering or evaporating wastewater from a sizings or painting process such that the filtered or evaporated wastewater contains a polyvinyl alcohol polymer in which the polyvinyl alcohol polymer is 20% to 30% by mass of the wastewater;

adding one of either carbonyl di-imidazole and ethylenediamine or 3-chloro-propionyl chloride and ethylenediamine to the filtered or evaporated wastewater so as to obtain a PVA-ethylenediamine hydrogel solvent;

adding dimethyl sulfoxide, boric acid, acetic acid and a surface active agent into the solvent both containing the PVA-ethylenediamine hydrogel solvent such that the dimethyl sulfoxide, boric acid, acetic acid and surface active agent are 20% to 30% by mass in the PVA-ethylenediamine;

coagulating the solvent bath with an acetone of a critical fluid phase;

stretching a polyvinyl alcohol polymer through the coagulated solvent bath at a temperature of 200° C. to 250° C. when the stretched polyvinyl alcohol polymer is wet; and

fixing the stretched polyvinyl alcohol polymer.