HOMOGENEOUS FILLED YARN

Abstract

The invention is concerned with filled multifilament yarn according to the present invention whereby the filler ratio, , in the yarn is greater than 0.004 times the IV of the UHMWPE present in the multifilament yarn (IV.sup.Y.sub.UH), i.e. 0.004 g/dL*IVy.sub.H* and whereby the tenacity (TEN, in cN/dtex) of the filled multifilament yarn is such that TENIV.sup.Y.sub.UH*(1.5-3.25*), or whereby the tenacity of a filled monofilament in the yarn is tenIV.sup.Y.sub.UH*(2-4.35*.sub.X). The invention is further concerned with a method to manufacture said multifilament yarn and articles comprising said multifilament yarn.

Claims

1. A filled multifilament yarn comprising a UHMWPE with an intrinsic viscosity (IV.sub.UH.sup.Y) of <20 dL/g, a filler with a numerical average diameter of at most 20 m in an amount such that the ratio () of the mass of filler to the combined masses of UHMWPE and filler is between 0.02 and 0.50, with 0.004 g/dL*IV.sub.UH.sup.Y, whereby the tenacity (TEN) of the filled multifilament yarn is such that TENIV.sub.UH.sup.Y*(1.5-3.25*).

2. A filled multifilament yarn comprising a UHMWPE with an intrinsic viscosity (IV.sub.UH.sup.Y) of <20 dL/g, a filler with a numerical average diameter of at most 20 m in an amount such that the ratio () of the mass of filler to the combined masses of UHMWPE and filler is between 0.02 and 0.50, with >0.004 g/dL*IV.sub.UH.sup.Y, whereby the tenacity of a filled monofilament in the filled multifilament yarn is tenIV.sub.UH.sup.Y*(2-4.35*).

3. The filled multifilament yarn of claim 1 wherein the ratio () of the mass of filler to the combined masses of UHMWPE and filler is between 0.04 and 0.40.

4. The filled multifilament yarn of claim 1 wherein 0.0045 g/dL*IV.sub.UH.sup.Y.

5. The filled multifilament yarn of claim 1 wherein the yarn has a tenacity of at least 5.0 cN/dtex.

6. The filled multifilament yarn of claim 1 wherein the diameter of the filler is at least 1 m.

7. The filled multifilament yarn of claim 1 wherein the diameter of the filler is at most 16 m.

8. The filled multifilament yarn of claim 1 wherein the filler has an aspect ratio of at least 2.0.

9. The filled multifilament yarn of claim 1 wherein IV.sub.UH.sup.Y is at most 18 dL/g.

10. Method for preparing the filled multifilament yarn of claim 1 comprising the steps of a) providing a UHMWPE having an intrinsic viscosity (IV.sub.UH.sup.O) of less than 24 dL/g, b) providing a filler with a diameter of at most 20 m, c) preparing a solution of the UHMWPE in a solvent, the solution comprising said filler in an amount such that the ratio () of the mass of filler to the combined masses of UHMWPE and filler is between 0.02 and 0.50, d) spinning the solution obtained in step c) through a multiple orifice die plate to form a solvent containing filled multifilament yarn, e) at least partially removing the solvent from the filled yarn of step d) before, during or after drawing the filled yarn at a total draw ratio of at least 20, to obtain said filled multifilament yarn, whereby the amount of filler is chosen such that 0.003 g/dL*IV.sub.UH.sup.O.

11. The method of claim 10 wherein is between 0.04 and 0.40.

12. The method of claim 10 wherein 0.0035 g/dL*IV.sub.UH.sup.O.

13. The method of claim 10, wherein IV.sub.UH.sup.O is less than 20 dL/g.

14. An article comprising the filled multifilament yarn of claim 1.

15. The article of claim 14 wherein the article is selected from the group consisting of fishing lines, fishing nets, ground nets, cargo nets, curtains, kite lines, dental floss, tennis racquet strings, canvas, woven cloths, nonwoven cloths, webbings, battery separators, medical devices, capacitors, pressure vessels, hoses, umbilical cables, automotive equipment, power transmission belts, building construction materials, cut resistant articles, stab resistant articles, incision resistant articles, protective gloves, composite sports equipment, skis, helmets, kayaks, canoes, bicycles and boat hulls, speaker cones, high performance electrical insulation, radomes, sails, and geotextiles.

Description

EXAMPLES

Comparative Experiment A and B (CE A and CE B)

[0070] Yarns of type A were produced following the process of Example 1 of WO2013149990 whereby a UHMWPE with an IV.sub.UH.sup.O of 27.0 dL/g was dry blended with an amount of 7 wt. %, 10 wt. % and 15 wt. % of mineral fibrils sold under the trade name CF10ELS by Lapinus, NL (numerical average diameter of 7.4 m, average length of 70 m, Moh's hardness of 3.5), for Comparative Experiments CE A-1, CE A-2 and CE A-3 respectively, and subsequently dissolved in decalin, to a total solids content (i.e. total content of polymer and filler) concentration of 9 wt. %. The so obtained solution was fed to a twin-screw extruder having a screw diameter of 25 mm, equipped with a gear pump. The solution was heated in this way to a temperature of 180 C. The solution was pumped through a spinneret having 64 holes, each hole having a diameter of 1 millimeter. The so obtained filaments were drawn in total with maximum drawing factor in the range of 170-200 and dried in a hot air oven. After drying the filaments were bundled into a yarn and wound on a bobbin. IV.sub.UH.sup.Y of fiber CE A-1 was measured at 22.2 dL/g.

[0071] Yarn of type B were obtained as described for yarn A with the difference that a UHMWPE with an IV.sub.UH.sup.O of 22.0 dL/g and different mineral fibers levels were used. The obtained filaments were drawn in total with a factor in the range of 180 to 210. IV.sub.UH.sup.Y of fiber CE B-2 was measured at 15.0 dL/g.

[0072] Subsequently yarns A and B were subjected to tensile measurements. Details about fiber composition, process and properties of CE A and CE B yarns are provided in Table 1.

TABLE-US-00001 TABLE 1 Dust emission X IV.sub.UH.sup.Y [dL/g] Total Draw Ratio TEN [cN/dtex] TEN/IV Cut Force [N] Yarn count [dtex] [g/kg yarn CE A-1 0.067 22.2 183 23.2 1.05 9.6 440 CE A-2 0.099 22.2 182 21.8 0.99 440 CE A-3 0.152 22.2 183 18.5 0.84 440 CE B-1 0 15 214 19.8 1.32 220 CE B-2 0.065 15 209 16.3 1.07 6.4 220 1.23 CE B-3 0.091 15 209 15.8 1.05 6.5 220 CE B-4 0.12 15 207 13.3 0.89 8.8 220 CE B-5 0.132 15 208 13.7 0.91 7.1 220 CE B-6 0.143 15 206 11 0.76 7.4 220 CE B-7 0.067 15 208 16.6 1.11 6.5 220

Example 1 (Ex.1)

[0073] Yarns Ex 1-1 and 1-2 were obtained as described for yarn A with the difference that a UHMWPE with an IV of 17.0 dig with respectively 14.3 wt. % and 6.5 wt. % of filler. The obtained filaments were drawn in total with a factor in the range of 200 to 210. Polymer IV in the obtained yarn was 11.3 dL/g.

Example 2 (Ex.2)

[0074] Yarns 2-1 and 2-2 were obtained identical to the process used for Yarn CE B, with the difference that 35 and 35.2 wt. % of filler have been used. Drawing ratios were respectively 200-210. Polymer IV in the final yarn was 15.0 dL/g.

Example 3 (Ex.3)

[0075] Yarns 3-1 and 3-2 were obtained identical to the process used for Yarn CE B, with the difference that another type of filler was used. Alphawool filler grade AW03 from Morgan (numerical average diameter of 3.9 m, average length of 70 m, Moh's hardness of 9), 15 wt. % of filler have been used for Yarn 3-1 and 25 wt. % for yarn 3-2. Drawing ratios were respectively 206-209. Polymer IV in the final yarn was 14.2 dL/g.

TABLE-US-00002 TABLE 2 Dust emission X IV.sub.UH.sup.Y [dL/g] Total Draw Ratio TEN [cN/dtex] TEN/IV Cut Force [N] Yarn count [dtex] [g/kg yarn Ex 1-1 0.143 11.3 210 15.7 1.39 7.6 220 Ex 1-2 0.065 11.3 204 16.1 1.44 10.3 440 0.63 Ex 2-1 0.35 15 205 9.0 0.60 9.5 220 Ex 2-2 0.352 15 206 10.6 0.71 9.6 220 Ex 3-1 0.15 14.2 209 16.7 1.18 10.1 440 Ex 3-2 0.25 14.2 206 11.6 0.82 10.3 440

[0076] Coefficient of variation have been measured for yarn samples CE B-2 and Ex 1-2. Results are reported in Table 3.

TABLE-US-00003 TABLE 3 IV.sub.UH.sup.O [dL/g] X [] IV.sub.UH.sup.Y [dL/g] TEN [cN/dtex] Ten [cN/dtex] Dpf [dtex] CV.sub.inter.sup.dpf [%] CV.sub.inter.sup.ten [%] CV.sub.intra.sup.TEN [%] CE B-2 22 0.065 15.0 16.3 20.1 3.37 15.68 16.34 1.12 Ex 1-2 17 0.067 11.3 16.1 22.4 3.09 7.82 9.65 0.45