FIELD: chemistry.
SUBSTANCE: polypropylene fibre has strength of 7 cN/dtex or higher; satisfies one or both conditions that (i) properties measured using a DSC method, where the shape of the endothermic peak on the DSC curve is the shape of a single peak with halfwidth 10°C or less, and change in enthalpy of fusion (ΔH) is equal to 125 J/g and (ii) presence of irregularities such that the thinness of the monofibre ranges from 0.1 to 3 dtex, and irregularities are formed on the surface, having mean average spacing from 6.5 to 20 mcm and average height from 0.35 to 1 mcm, as a result of presence of alternating protruding regions, having a large diameter, and non-protruding regions having a small diameter, on the axis of the fibre. The method of producing polypropylene fibre involves preliminary drawing of unstretched polypropylene fibre, having IPF of 94% or higher, at 120-150°C with drawing ratio of 3-10, followed by drawing at 170-190°C with drawing ratio of 1.2-3.0 at deformation rate of 1.5-15 times/min and drawing tension of 1.0-2.5 cN/dtex.
EFFECT: obtaining polypropylene fibre having unique strength, heat-resistance and water-retention properties.
17 cl, 5 dwg, 9 tbl, 70 ex
