US2957848A

US2957848A - Synthetic thread or fiber and process for the production thereof

Info

Publication number: US2957848A
Application number: US580167A
Authority: US
Inventors: Lotz Rudolf
Original assignee: Glanzstoff AG
Current assignee: Glanzstoff AG; Vereinigte Glanzstoff Fabriken AG
Priority date: 1955-08-08
Filing date: 1956-04-24
Publication date: 1960-10-25
Anticipated expiration: 1977-10-25

Description

SYNTHETIC THREAD R FIBER AND PROCESS FOR THE PRODUCTION THEREOF Rudolf Lotz, Kliugenberg (Main),

Vereinigte Glanzstolf-Fabriken feld, Germany No Drawing. Filed Apr. 24, 1956, Ser. No. 580,167 -Claims priority, application Germany Aug. 8, 1955 18 Claims. (Cl. 260-45.7)

Germany, assignor to A.G., Wuppertal-Elber- This invention relates to an improved synthetic thread or fiber and to a process for producing the same, and is a continuation-in-part of my application, Serial No. 572,223, filed March 19, 1956, now abandoned.

It is well known that threads or fibers of synthetic high polymers have an electrostatic charge which is detrimental in later operations on the threads, such as weaving.

Attempts have been made to reduce the amount of the electrostatic charge on the threads or fibers by additional processing of the threads, for example, by treating the formed threads with solutions of low molecular weight condensation products. By this treatment the condensation product becomes fixed on the threads and remains fixed on the threads through subsequent laundering operations. Other treatments employed involve chemical coupling reactions such as are involved in the substantive dyeing of threads. with reduced electrostatic charge but is disadvantageous in that the substances applied by the treatment cause yellowing of the threads. Furthermore, machinery used in later processing of the treated, threads and fibers becomes corrodeddue to the treating solutions employed. The corrosion of the machinery,

in turn, has detrimental elfects on the threads and fibers.

- One of r the objects of the invention is to provide a synthetic thread or fiber of reduced electrostatic charge and aprocess for producing the same.

Another object of the invention is to provide a process for producing a synthetic thread or fiber of reduced electrostatic charge which process will not cause discoloration of the'threads or fibers and which will not cause corrosion of machinery employed in later operations on the threads In accordance with the invention, these objects are accomplished by incorporating in the linear polymer prior to the spinning of the thread or fiber a derivative of methane This type of after treatment produces thread or ethane which dissociates into free radicals having tri- 'valent carbon. The derivative is added to tthe polymer just prior to spinning the thread or fiber or is added prior to polymerization to the monomer from which the linear polymer is formed.

. The monomers polymerized to form the linear polymers from which the threads or fibers are spun are any of those customarily employed in producing linear high polymers by polycondensation, in which some atomic displacement. occurs, or by true polymerization in which no atomic displacement occurs. Examples of such monomers' are lactams, hexamethylenediammoniumadipate, 'terephthalic acid dimethyl or diglycol esters, and acrylic acid nitrile. These monomers or other like monomers are polycondensed or polymerized in the presence of the aforementioned methane or ethane derivatives by otherwise conventional methods.

Any methane or ethane derivative or mixtures thereof are suitable which dissociate in solution into free radicals having trivalent carbon. The derivatives found to be esylchloromethane, triphenylcarbinol, diphenylmonobiphen- Meter,

2,957,848 Patented Oct. '25, '1960 ylmethane, phenyl-di-biphenylmethane, diphenyl-a-naphthylmethane, hexaphenylethane, hexa-p-diphenylethane, tetraphenyl-di-biphenylethane, diphenyl-tetra-biphenylethane, and hexa-biphenylethane. V

1 The above-named derivatives or anti-static additives can best be represented by the general formula and wherein R R R512 R and R are monovalent aryl radicals selected fromthe group consisting of unsubstituted and chloro-substituted phenyl, naphthyland diphenyl radicals. These compounds are more fully discussed in Gilman, Organic Chemistry, vol. I, second ed., John Wiley & Sons, New York, pp. 581-601. Gilman notes that these compounds are characterized by their property of dissociating into free radicals which are referred to as the triarylmethyls and in which the carbon atom is trivalent, the odd electron resonating among nine positions according to prevalent theories of resonance. It is this resonance which is believed to contribute to the unique stability of the trivalent carbon atom.

The particular anti-static compound employed is added to the monomer to be polymerized or the polymer in an amount which is relatively small compared to the amount of monomer or polymer employed, preferably an amount ofiabout 0.1to 5% by weight of the monomer or polymer. The anti-static compounds are added to the monomers or polymers either directly or in solution employing an appropriate solvent for the anti-static compound such as a-chloronaphthalene or 1,2,4-trichlorobenzol.

Threads or fibers produced from linear high polymers have an electrostatic charge which is measurable by a megohm-meter, based on the principle that the electrical resistance of the thread or fiber increases proportionally with increased electrostatic charge on the thread or fiber. A suitable megohm-meter, known as a Multi-Megohmis obtainable from Wissenschaftlich-Technische Werkstiitten, Wessobrunn, Upper Bavaria, Germany. It has been found that the electrostatic charge on a thread is excessive and detrimental to later processing of the thread if the measured resistance of the thread is 5 10 ohms or more.

The invention will be further illustrated but is not limited by the following examples in which the quantities are stated in parts by weight unless otherwise indicated.

Example 1 A linear high polymerwas produced by heating grams of terephthalic acid dimethyl ester with 20 milligramsof zinc oxide and an equimolecular excess of ethylene glycol, in a nitrogen atmosphere until a clear solution was formed. To this solution was added 2 grams of hexaphenylethane, and the mixture was further heated in the nitrogen atmosphere for three hours at normal atmospheric pressure with the temperature of the mixture gradually increased to about '200 C.- When glycol separation was substantially completed, the mixture was further heated to 265 C. for one hour. Vacuum was then applied to remove traces of glycol. The polycondensate obtained had a K-value of 50. Threads produced from the polycondensate had an electric resistance of about 1x10 ohms; indicating a sufiiciently low electrostatic charge. A polycondensate produced by the same process with'the exception that the hexaphenylethane was omitted was 3 spun into threads which were found to have an electrical reslstance between 1 10 and 1 10 ohms, indicating an excessively large electrostatic charge.

Example 2 100 grams of terephthalic acid diglycol ester was dissolved in 350 grams of a-methylnaphthalene with heating during which 20 milligrams of boron trioxide were added.

,To the solution obtained was added 1.5 grams of tri- Example 3 A mixture containing 113 grams of a lactam having the formula 1.2 grams e-amino capronic acid, 8 milliliters distilled water and 1.2 grams diphenyl-mono-biphenylmethane was heated to a condensing temperature (about 235 C. bath temperature). After 7 hours of heating, a polyamide was formed from which synthetic threads were produced. The electric resistance of the threads was found to be about 1X10 ohms, indicating a sufficiently low electrostatic charge.

Example 4 400 grams of freshly distilled acrylic acid nit-rile was suspended in 400 milliliters of water containing 0.5 gram ammonium persulfate, 1.0 gram ammonium sulfite and 2.0 grams of an emulsifying agent (a polyethoxylated fatty acid formed from 6 parts ethylene oxide and 1 part stearic acid). To this suspension was added 0.1 gram triphenylchloromethane and 0.1 gram hexaphenylethane. The mixture was then heated at 235 C. for 4 to 6 hours with constant agitation. The resulting polymerizate was removed from the mixture by precipitation with sodium chloride, filtered and washed with water. Threads produced from the polymerizate had an electrical resistance of 1x10 ohms, indicating a sufficiently low electrostatic charge.

Example 5 17 parts by weight of polyacrylic nitrile were dissolved in 83 parts by weight of dimethyl formarnide. To this solution was added 0.5 0f triphenylchloromethane and the solution then spun into threads. The resulting threads had an electrical resistance of 0.11 X ohms, indicating a sufficiently low electrostatic charge.

Example 6 17 parts by weight of polyacrylic nitrile were dissolved in 83 parts by weight of dimethyl formamide. To this solution was added 1% hexaphenylethane and the resulting mixture spun into threads. The electrical resistance of the threads was found to be 014x10 ohms, indicating a sufliciently low electrostatic charge.

Example 7 To 100 parts by weight of a polyamide, formed from caprolactam, was added 1% diphenyl-a-naphthyhnethane, after which the mixture was melted and spun into threads. The electrical resistance of the threads was found to be 10 ohms, indicating a sufiiciently low electrostatic charge.

4 Example 8 parts by weight of polyethylene terephthalate (K- value of 50) was added to 100 parts by weight of achloronaphthalene containing 0.5% of hexaphenylethane. After removing most of the a-chloronaphthalene by distillation, the mixture was melted and spun into threads. The electrical resistance of the threads was found to be 4X10 ohms, indicating a sufficiently low electrostatic charge.

All of the threads or fibers produced according to the invention in the above examples had a sufficiently reduced electrostatic charge to avoid detrimental electrostatic effects in later processing of the threads. The anti-static methane or ethane derivatives incorporated in the polymer threads or fibers are chemically resistant and accordingly are not washed out of the polymer threads in subsequent laundering operations. Furthermore, the threads or fibers produced according to the invention are not discolored due to the special processing and because of their antistatic characteristics are highly desirable in the textile industry.

The invention is hereby claimed as follows:

1. An improved synthetic fibrous material comprising a linear high molecular weight synthetic fibrous polymer selected from the group consisting of polycaprolactam, polyhexamethylene adipamide and polyethylene terephthalate to which there has been added an anti-static compound having the general formula R1 RQC-Y Rt wherein Y designates a member selected from the group consisting of hydrogen, chlorine, hydroxy and R4 C--R;

R0 and wherein R R R R R and R are monovalent aryl radicals selected from the group consisting of unsubstituted and chloro-substituted phenyl, naphthyl and diphenyl radicals.

2. A synthetic fiber according to claim 1 wherein said polymer is polycaprolactam.

3. A synthetic fiber according to claim 1 wherein said polymer is polyethylene terephthalate.

4. A synthetic fiber according to claim 1 wherein said anti-static compound is hexaphenylethane.

5. A synthetic fiber according to claim 1 wherein said anti-static compound is triphenylchloromethane.

6. A synthetic fiber according to claim 1 wherein said anti-static compound is diphenylmonobiphenylmethane.

7. A synthetic fiber according to claim 1 wherein said polymer contains said anti-static compound in an amount of about 0.1% to about 5% by Weight of the polymer.

8. A synthetic fiber according to claim 1 wherein said anti-static compound is hexa-p-diphenylethane.

9. A synthetic fiber according to claim 1 wherein said anti-static compound is hexa-biphenylethane.

10. A synthetic fiber according to claim 1 wherein said polymer is polyhexamethylene adipamide.

11. In a process for producing a synthetic fibrous material wherein a monomer is polymerized to form a linear high molecular weight polymer selected from the group consisting of polycaprolactam, polyhexamethylene adipamide and polyethylene-terephthalate and the polymer is spun into a filamentary product, the improvement for reducing electrostatic charges on the filamentary product which comprises: adding to said fibrous material prior to spinning the filamentary product an anti-static compound having the general formula wherein Y designates a member selected from the group consisting of hydrogen, chlorine, hydroxy and /R4 -C R; u and wherein R R R R R and R are monovalent aryl radicals selected from the group consisting of un:

substituted and chloro-substituted phenyl, napthyl d ed diphenyl radicals, said anti-static compound being a in an amount suflicient to avoid detrimental electrostatic charges in subsequent processing of the filamentary product.

12. The improvement according to claim 11 wherein said anti-static compound is incorporated in the polymer in an amount of about 0.1% to about 5% by weight of the polymer.

13. The improvement according to claim 11 wherein said anti-static compound is dissolved in a-chloronaphthalene prior to incorporation in the polymer.

14. The improvement according to claim 11 wherein said anti-static compound is dissolved in 1,2,4-trichlorobenzol.

15. The improvement according to claim 11 wherein said anti-static compound is hexaphenylethane.

16. The improvement according to claim 11 wherein said anti-static compound is triphenylchloromethane.

17. The improvement according to claim 11 wherein said anti-static compound is diphenylmonobiphenylmethane.

18. The improvement according to claim 11 wherein the anti-static compound is incorporated in the polymer by addition prior to polymerization to the monomer from which the polymer is formed.

References Cited in the file of this patent UNITED STATES PATENTS 2,115,896 Wiezevich May 3, 1938 2,223,171 Gaylor Nov. 26, 1940 2,445,739 Rowland et a1 July 20, 1948 2,763,635 Tucker et al Sept. 18, 1956 2,841,569 Rugg et al. July 1, 1958 FOREIGN PATENTS 455,527 Canada Mar. 29, 1949 OTHER REFERENCES Wooding et a1.: Chemical Society Journal, January- 25 March 1952, pages 774-779.

Claims

1. AN IMPROVED SYNTHETIC FIBROUS MATERIAL COMPRISING A LINEAR HIGH MOLECULAR WEIGHT SYNTHETIC FIBROUS POLYMER SELECTED FROM THE GROUP CONSISTING OF POLYCAPROLACTAM, POLYHEXAMETHYLENE ADIPAMIDE AND POLYETHYLENE - TEREPHTHALATE TO WHICH THERE HAS BEEN ADDED AN ANTI-STATIC COMPOUND HAVING THE GENERAL FORMULA