DE202010006462U1 - Monofilaments of thermoplastic polymers and their use - Google Patents

Abstract

Claimed
1. a monofilament consisting of melt-spinnable polymers, characterized in that it contains 0.001% by weight to 2.00% by weight of a fatty acid amide or oleic acid amide mixture, 1 ppm by weight to 500 ppm by weight of a phosphitic co-stabilizer, 0, 01 wt% to 1.50 wt% of a calcium carbonate, 0.001 wt% to 5.0 wt% of a polymeric carbodiimide and 0.01 wt% to 3.00 wt% of a monomeric carbodiimide.
2. A monofilament according to claim 1, characterized in that it is the polyester melt-spinnable polymers, preferably polyethylene terephthalate or polytrimethylene terephthalate or polybutylene terephthalate or polyethylene naphthalate or mixtures of the aforementioned polymers.
3. a monofilament according to claim 1 and 2, characterized in that it may additionally contain a dye.
4. a monofilament according to claims 1 to 3, characterized in that the cross section is round, n-square with n ≥ 3, or point or axisymmetric with respect to the center of the monofilament cross-section.
5. a textile surface or construction, the monofilaments ...

Description

Technical area

The This invention relates to hydrolysis resistant monofilaments having reduced Surface friction and dirt-repellent properties.

State of the art

monofilaments made of synthetic polymers found in numerous fields of application Use, for example in paper machine clothing, sieves, bristles, Conveyor belts, seat belts, etc.

In Paper machines will be a suspension of pulp fibers on a Forming screen applied, roughly drained there, then Further water in a press section is mechanically removed from the paper web pushed out. In the dryer section is using heat Residual water is largely eliminated and then the wound on their residual moisture set paper web. In all In three areas, the paper web is guided by rotating screens. In the sheet forming section (forming fabric) and in the dryer section one uses predominantly sieves made of polyester monofilaments, in the press section sieves and felts made of polyamides.

Because of high temperatures and moisture build the polyester chains in the drying section hydrolytically. This will increase the useful life reduced a drying wire. Responsible for the hydrolytic degradation are the carboxyl groups in the polyester.

Extend can be the life of a dryer on the one hand by using polyesters with low carboxyl groups, z. B. <10 mmol COOH / kg polyester. In addition, the carboxyl groups can be chemically seal with carbodiimides, z. B. with Stabaxol by Rhein Chemie Rheinau GmbH, Düsseldorfer Str. 23-27, 68219 Mannheim. By using mixtures of monomeric and polymeric Carbodiimide one achieves a kind of depot effect, so that with it the service life of dryer fabrics is further increased.

Especially due to the increased proportion of recycled paper in recent years Also increases the amount of dirt in the stock suspension. Mostly gone through these dirt particles the forming and pressing section, but in the dryer section especially sticky with the elevated temperatures remain Sticking dirt on the screen, so that the period of use of the Sieve not only by the hydrolytic degradation, but also by Contaminations are limited.

Therefore, sieves are required which are manufactured from hydrolysis-resistant and dirt-repellent monofilaments. For more than 20 years, halogenated polyolefins have been used, which are mixed with the carbodiimide in the polyester matrix. Examples are the EP 506983 A1 and the WO 9405835 A1 which preferably use fluoropolymer compounds as halogenated polyolefins.

Of the Effect of soil repellency is based on increasing the surface energy density of the polymer by the halogenated polyolefins. Corresponding Young's relationship is through a higher interfacial energy the wetting angle is greater and the adhesion of a Foreign body on the surface of the polymer thus reduced.

modern Paper machines are always running faster, the energy consumption alone for driving these machines is significant. For this Reason is always beside the hydrolysis resistance and the dirt instruction stronger the demand for reduced friction or improved Sliding properties provided.

Solved This object is achieved by a further addition of a Fattyäureamidhaltigen Additive.

fatty acid amides are waxes based on long carbon molecular chains. They slowly migrate to the surface and form there a long-term film with good sliding properties and high long-term temperature resistance up to 220 ° C.

fatty acid amides are also a water repellent, d. H. support them the dirt repellent properties by increasing the Surface energy density.

As a result, the previously used, much more expensive fluoropolymers as dirt-repellent Ad ditive replaced.

Example:

In several series of experiments were low-carboxyl polyester Base polyethylene terephthalate used, especially the raw material type RT 12 of Invista Resins & Fibers GmbH, Philipp-Reis-Str. 2, 65795 Hattersheim. This type of PET has after solid condensation <10 mmol COOH / kg. By addition of 0.7% by weight Stabaxol1 the Rhein Chemie and 5.0% by weight stabilizer 9000 MB-T, a polymeric Carbodiimide from Sukano Products Ltd., Chaltenbodenstr. 23, 8834 Schindellegi / Switzerland, the remaining carboxyl groups of the Polyester closed.

When new component 5.0% by weight of Monoslip 230310 PET are added. The recipe of this addition was made by Mr. Udo Müller, Parkstr. 18, 96450 Coburg developed and applied for a patent. Monoslip contains the inventive Addition of fatty acid amides, a phosphite-containing co-stabilizer and nucleating agent in a PBT-based masterbatch.

in the If necessary, a color masterbatch of the polymer mixture was also added.

Subsequently, this polymeric mixture was melted in an extruder, forced through a gear pump in a spin pack, filtered through sieves and steel sand, pressed through fine bores or spun, quenched in a water bath, then stretched several times drafting under heat several times or thermofixed and to Monofilaments wound on disc coils. This production process for monofilaments is state of the art, so that it need not be discussed in detail. Textile values: test number grade Diameter [mm] colour produced quantity [kg] V 8190 930 XL 0,600 - 1,121.2 V 9061 930 XL 0.900 - 198.8 V 9131 930 XL 0.900 blue 1,238.1 test number Titre [dtex] Strength [N] spec. Firmly. [CN / tex] Elongation at break [%] Reference strain at 27 cN / tex [%] Thermal shrinkage 180 ° C [%] V 8190 3885 162.5 41.8 17.4 6.3 18.2 V 9061 8709 383 44.0 15.7 6.3 20.2 V 9131 8697 388 44.6 15.1 6.3 20.0

The Goods were then woven and under practical conditions against comparable standard sieves made of dirt-repellent monofilaments, which were modified with fluoropolymers tested.

Especially To emphasize are the low sliding friction, resulting in a clear reflected lower drive power, as well as the dirt-repellent Properties. It should be emphasized that not only the pollution is lower than the standard sieves, but the Sieves invention can be with the high pressure cleaner also easier to clean again!

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - EP 506983 A1 [0007]
• WO 9405835 A1 [0007]

Claims (1)

Claimed 1. consisting of a monofilament made of melt-spinnable polymers, characterized in that it 0.001% by weight to 2.00% by weight of a fatty acid amide or oleic acid amide mixture, 1 ppm by weight to 500 ppm by weight of a phosphitic co-stabilizer, 0.01 wt% to 1.50 wt% of a calcium carbonate, 0.001 wt% to 5.0 % By weight of a polymeric carbodiimide and 0.01% by weight to 3.00% by weight of a monomeric carbodiimide. 2. a monofilament according to claim 1, characterized in that it is melt-spinnable Polymers to polyester, preferably to polyethylene terephthalate or Polytrimethylene terephthalate or polybutylene terephthalate or polyethylene naphthalate or mixtures of the aforementioned polymers. Third A monofilament according to claims 1 and 2, characterized in that that it can additionally contain a dye. 4th A monofilament according to claims 1 to 3, characterized that the cross-section is round, n-angular with n ≥ 3, or point or axisymmetric with respect to the center of the monofilament cross-section is. 5. a textile surface or construction that Monofilaments according to the preceding claims. 6th the use of a textile surface according to claim 5 in Paper machine clothing, filter fabrics or conveyor belts.