US2495277A - Compositions, including a hydrogenated semidrying oil and methacrylate resin mixture as a lubricant - Google Patents

Description

Patented Jan. 24, 1950 COMPOSITIONS, INCLUDING A HYDROGEN- A'IED SEMIDRYING OIL AND METHACRY- LATE RESIN MIXTURE AS A LUBRICANT Victor A. Navikas, Lancaster, Pa., asslgnor to Armstrong Cork Company, Lancaster, Pa., a corporation of Pennsylvania No Drawing. Application December 31, 1942, Serial No. 470,915

This invention relates to extrudable cork compositions and, more particularly, to an extrudable cork composition containing an improved lubricant.

Cork compositions have been extruded heretofore in various forms for use as expansion joint materials, rods, discs, gaskets, and the like by means of a suitable extrusion device such as that disclosed in United States Patent No. 1,453,617, granted May 1, 1923, to William G. Bond. In such device, cork composition is placed at the entrance of an extruding tube, and a reciprocable plunger is used to force the composition into the tube and to compact it therein into the desired form. Heating and cooling zones are provided in the extrusion tube in order to set the binder of the composition. Cork is highly frictional and it has been found that frequently the composition freezes in the extrusion tube with resulting damage to the tube or considerable time consumed in removing the tube from the device and removing such composition from the tube. Many cork compositions can be extruded for short periods but it is very difficult to formulate a satisfactory composition which can be extruded continuously over long periods of time. Likewise, it has been found that, due to the highly frictional qualities of the cork particles, the mass in the center of the tube exhibits a tendency to flow to a greater extent than those portions of the composition adjacent the walls of the tube so that the edges of the extruded product are compacted to a considerably greater extent than its central portion. This results in a product of uneven density which is highly undesirable and unsatisfactory. To eliminate to a considerable extent the disadvantages discussed above, it has been proposed to add various lubricants to the cork composition in order to decrease its frictional characteristics thus aiding in extrusion. Various lubricantshave been proposed but none of them has been highly satisfactory for in most cases they penetrate the cork particles which require the use of an excessive amount of lubricant thus increasing considerably the cost of the composition and decreasing its quality, for large amounts of lubricant aflect the binder so that it fails to bind the particles securely to one another.

The chief object of my invention is to provide an improved cork composition capable of extrusion. An object of my invention is to provide a novel and useful lubricant for cork compositions. A further object is to provide an extrudable cork composition containing a lubri- 7 Claims. (Cl. 26017.4)

cant. A still further object is to provide an extrudable cork composition containing a lubricant which includes a bodying agent to prevent substantial penetration of the lubricant into the cork particles. Other objects of my invention will be apparent from the following description.

The cork composition of my invention comprises cork particles, a binder therefor, preferably, capable of being set by heat, and a lubricant to aid in the extrusion of the mass. The lubricant is composed of a mixture of hydrogenated semi-drying oils, such as hydrogenated cottonseed oil, and a bodying agent to retard or to prevent penetration of the cottonseed oil into the cork particles by increasing the viscosity thereof. Preferably, the lubricant is composed of a mixture of hydrogenated cottonseed oils, one oil being hydrogenated to a considerably greater extent than the other and having a higher melting point. I have found a hydrogenated cottonseed oil having a melting point of about 98 F. and a more highly hydrogenated cottonseed oil, a wax-like product, having a melting point of about 140 F., form a satisfactory mixture. To such mixture is added a bodying agent which is used to increase the viscosity of the mixture. The preferred bodying agent is a methacrylate resin, which is referred to hereinafter as resin A, and which I believe is a polymerized compound, produced by copolymerizing a mixture of n-butyl methacrylate and isobutyl methacrylate, having a molecular weight of at least 10,000 and which is thermoplastic and soluble in the hydrogenated semi-drying oil. Polymethyl methacrylate, polypropyl methacrylate, or similar polymers having a molecular weight of at least 10,000 may be used in place of the preferred resin with satisfactory results. A suitable lubricant may be formulated as follows, all proportions being given by weight.

Parts Hydrogenated cottonseed oil (M. P.

140 F.) 30 to Hydrogenated cottonseed oil (M. P.

98 F.) 20 to 50 Methacrylate resin (resin A above).. 6 to 20 In the preparation of the lubricant, the hydrogenated cottonseed oil (M. P. 98 F.) is melted and the hydrogenated cottonseed oil (M. P. F.) added thereto, melted and thoroughly mixed. When the temperature is at 260 F., the methacrylate resin A is added. While constantly stirring the mixture, the temperature is raised to 290 -300 F. and in ten to twenty minutes, the batch is in solution and ready to be added to the cork particles for use as a lubricant. I show below various specific luoricants formulated for use:

I have found for most satisfactory results the amount of methacrylate resin included in the lubricant should fall within the range of to 12 /2 of the total weight of the lubricant. While larger or smaller amounts of methacrylate resin, that is, within the limits of 6% to based on the weight of the cottonseed oils, may be used, for most satisfactory results the amount of resin used should fall within the range of 10% to li /2% of the total weight of the lubricant.

The lubricant prepared as above may be included with any of the cork compositions customarily prepared for extrusion. In such compositions, the binder is usually set by heat and I have shown below a. number of satisfactory binders for extrudable compositions:

The catalyst is composed of water 20%, sodium bodying agent retains the lubricant on the particles as a coating and thus enables it to perform its required function. Generally speaking, the majority of high molecular weight resins may be used as bodying agents for the above described lubricant but those described above I have found preferable and available on the open market.

If desired, the extruded products formed from the above compositions may receive further .treatment at elevated temperatures to increase the set of the binder. Such treatment aids considerably in overcoming low binder set when extrusion is carried on at low temperatures or if large amounts of lubricant be used.

My invention provides an improved cork composition which may be extruded and which is formulated to permit the extrusion device to be operated continuously for long periods of time hydroxide 15%, and glycerine 65%. To form the Per cent Per cent Gelatine 27 2o Glycerine 33 25 Water In Example 1, approximately 6.5 parts by without requiring stoppage or shut-downs in order to eliminate composition jammed in the extrusion tubes. I provide a lubricant for extrudable cork compositions which is highly satisfactory and economical.

While I have described certain preferred embodiments of my invention, it will be understood my invention is not limited thereto since it may be otherwise embodied within the scope of the following claims.

I claim:

1. An extrudable cork composition which comprises cork particles, a binder capable of being set by heat, a mixture of hydrogenated cottonseed oils in which one oil has a melting point of about 98 F. and another has a melting point of about 140 F., and butyl methacrylate resin having a molecular weight above 10,000.

2. An extrudable cork composition mix which comprises a mass of cork particles, a binder therefor, and a lubricant coating the cork particles without substantial penetration into the body thereof, said lubricant including a mixture of hydrogenated cottonseed oils in which one oil has a melting point of about 98 F. and another 5 has a melting point of about 140 F., and a bodyweight of such binder may be mixed with 83 parts 50 lubricant be included and that the softening 60 point of the lubricant must be lower than the temperature of extrusion. By softening point or melting point I mean a temperature at which the lubricant is soft enough to flow. Generally be low enough to afford fluidity, a large portion of the lubricant is absorbed by the cork particles. I have found that a bodying agent as described above increases the viscosity of the lubricant and is of a molecular size suiilciently great to retard or prevent penetration of the lubricant into the cork particles. The efficacy of the lubricant may be due to its viscosity or to the large molecular size of the bodying agent or to a combination of both factors. In any event. the addition of the ing agent for the oils consisting essentially of a thermoplastic methacrylate resin having a molecular weight above 10,000 selected from the group consisting of poiybutyl methacrylate, polymethyl methacrylate, and polypropyl methacrylate.

3. An extrudable cork composition mix which comprises a mass of cork particles, a binder therefor, and a lubricant coating the cork particles without substantial penetration into the body thereof, said lubricant including a mixture of hydrogenated cottonseed oils in which one oil has a melting point of about 98 F. and another has a melting point of about 140 F., and a bodying agent for the oils consisting essentially of a thermoplastic methacrylate resin having a molecular weight above 10,000 selected from the group consisting of polybutyl methacrylate, polymethyl methacrylate, and polypropyl methacrylate, said speaking if the softening point of the lubricant 65 oils and resin being in approximately the following proportions:

Per cent Hydrogenated cottonseed oil (M. P.

98 F.) 30 to '70 Hydrogenated cottonseed oil (M. P.

F.) 20 to 50 Methacrylate resin 6 to 20 4. An extrudable cork composition mix which comprises cork particles, a binder therefor, and a mixture of hydrogenated cottonseed oils in which one oil has a melting point of about 98 F. and another has a melting point of about 140 F.. said last named oil being hydrogenated to a considerably greater extent than the first named oil. and butyl methacrylate resin having a molecular weight above 10,000.

5 An extrudable cork composition mix which comprises a mass of cork particles, a binder therefor, and a lubricant coating the cork particles without substantial penetration into the body thereof, said lubricant including a mixture of hydrogenated cottonseed oils in which one oil has a melting point of about 98 F. and another has a melting point of about 140 F., and a thermoplastic methacrylate resin bodying agent for the oils having a molecular weight above 10,000 and consisting essentially of a polymerization product of esters from methacrylic acid and normal butyl and isobutyl alcohol.

6. An extrudable cork composition mix which comprises a mass of cork particles, a binder therefor, and a lubricant coating the cork particles without substantial penetration into the body thereof, said lubricant including a mixture of hydrogenated cottonseed oils in which one oil has a melting point of about 98 F. and another '7. An extrudable cork composition mix which comprises a mass of cork particles, a binder therefor, and a lubricant coating the cork particles without substantial penetration into the body thereof, said lubricant including a mixture of hydrogenated cottonseed oils in which one oil has a melting point of about 98 F. and another has a melting point of about F., and a thermoplastic polypropyl methacrylate resin bodying agent for the oils having a molecular weight above 10,000.

VICTOR A. NAVIKAS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,050,272 Canning Aug. 11, 1936 2,082,278 Ferguson June 1, 1937 2,204,517 Strain June 11, 1940 2,273,780 Dittmar Feb. 17, 1942 2,365,508 Austin Dec. 19, 1944 FOREIGN PATENTS Number Country Date 416,412 Great Britain Sept. 10, 1934

Claims (1)

1. 2. AN EXTRUDABLE CORK COMPOSITION MIX WHICH COMPRISES A MASS OF CORK PARTICLES, A BINDER THEREFOR, AND A LUBRICANT COATING THE CORK PARTICLES WITHOUT SUBSTANTIAL PENETRATION INTO THE BODY THEREOF, SAID LUBRICANT INCLUDING A MIXTURE OF HYDROGENATED COTTONSEED OILS IN WHICH ONE OIL HAS A MELTING POINT OF ABOUT 98*F. AND ANOTHER HAS A MELTING POINT OF ABOUT 140*F. AND A BODYING AGENT FOR THE OILS CONSISTING ESSENTIALLY OF A THERMOPLASTIC METHACRYLATE RESIN HAVING A MOLECULAR WEIGHT ABOVE 10,000 SELECTED FROM THE GROUP CONSISTING OF POLYBUTYL METHACRYLATE, POLYMETHYL METHACRYLATE, AND POLYPROPYL METHACRYLATE.