Polyoxymethylene fibers, production thereof and use thereof
View Patent ↗Described are fibers comprising a polyoxymethylene copolymer having an ISO 1133 MVR melt index (determined at 190° C. under a load of 2.16 kg) in the range from 0.3 to 30 ml/10 min which possess a bend recovery (measured by the double loop method in air and/or water) of not less than 125° C. These fibers are useful in brushes.
1. Fibers comprising a polyoxymethylene copolymer having an ISO 1133 MVR melt index (determined at 190° C. under a load of 2.16 kg) in the range from 0.3 to 30 ml/10 mm which possess a bend recovery (measured by the double loop method in air and/or water) of not less than 125° C.
2. The fibers according to claim 1 wherein the polyoxymethylene copolymer has a melting point of not less than 140° C. and a weight average molecular weight M w in the range from 5000 to 200 000.
3. The fibers according to claim 1 wherein the polyoxymethylene copolymer has an MVR value (190/2.16) in the range from 1 to 10 ml/10 min.
4. The fibers according to claim 1 wherein the polyoxymethylene copolymer, as well as recurring oxymethylene groups, comprises from 0.5 to 10 mol % of structural units derived from comonomers.
5. The fibers according to claim 1 wherein the polyoxymethylene copolymer has a crystallization half-life of not less than 30 seconds and preferably not less than 100 seconds, determined by cooling from 200° C. to a temperature which is 10° C. below the melting temperature of that POM copolymer at a cooling rate of 80° C./minute and maintaining this temperature at this observation temperature.
6. The fibers according to claim 5 which comprise no nucleating agents.
7. The fibers according to claim 1 wherein the polyoxymethylene copolymer, as well as recurring oxymethylene groups of the formula I, comprises from 0.5 to 10 mol % of oxyalkylene groups of the formula II
—[CH 2 —O]— (I),
—[(CH 2 —) m —O] y — (II)
where m is an integer from 2 to 4 and y is 1 or 2.
8. The fibers according to claim 1 which possess a bend recovery (measured by the double loop method in air and/or water) of not less than 130°.
9. The fibers according to claim 1 which possess a DIN 53 834-1 tensile strength of up to 45 cN/tex.
10. The fibers according to claim 1 which possess a DIN 53834-1 breaking extension of up to 100%.
11. The fibers according to claim 1 which are monofilaments.
12. A process for producing the fibers according to claim 1 which comprises the measures of
i) extruding a melt comprising a polyoxymethylene copolymer having an ISO 1133 MVR melt index (determined at 190° C. under a load of 2.16 kg) in the range from 0.3 to 30 ml/10 min through a spinneret die,
ii) introducing the resultant filament into a bath of liquid having a temperature of less than 150° C.,
iii) withdrawing the resultant filament,
iv) single or multiple drawing to an overall draw ratio of not more than 6:1, and
v) optionally heating the drawn filament while allowing shrinkage.
13. The fibers according to claim 1 wherein the polyoxymethylene copolymer has a melting point of not less than 140° C. and a weight average molecular weight M w in the range from 7000 to 150 000.
14. The fibers according to claim 1 wherein the polyoxymethylene copolymer has an MVR value (190/2.16) in the range from 1 to 3 ml/10 min.
15. The fibers according to claim 1 wherein the polyoxymethylene copolymer, as well as recurring oxymethylene groups, comprises from 1 to 5 mol % of structural units derived from comonomers.
16. The fibers according to claim 1 wherein the polyoxymethylene copolymer, as well as recurring oxymethylene groups, comprises from 1.5 to 4 mol % of structural units derived from comonomers.
17. The fibers according to claim 1 wherein the polyoxymethylene copolymer, as well as recurring oxymethylene groups of the formula I, comprises from 1 to 5 mol % from 1.5 to 3 mol % of oxyalkylene groups of the formula II
—[CH 2 —O]— (I),
—[(CH 2 —) m —O] y —(II)
where m is 2 and y is 1 or 2.
18. The fibers according to claim 1 which possess a DIN 53834-1 tensile strength of up to 40 cN/tex and a DIN 53834-1 breaking extension in the range from 25% to 100%.
19. A brush which comprises the fibers according to claim 1 .
20. The brush according to claim 19 wherein the fibers are inserted in the form of monofilaments.
21. The brush according to claim 19 wherein the brush is a toothbrush, hairbrush, artist brush, writing brush, industrial brush, paint brush, paint roller, paint pad, cosmetic brush, road and domestic cleaning brush or a body care brush.