MXPA00002605A - Polyvinyl chloride compositions useful as floor coverings - Google Patents

Abstract

These compositions encompass products made of flexible plasticized PVC, usually formulated as a dispersion of high molecular weight PVC resins in a special blend of plasticizers. Both PVC resins and plasticizers are chosen from a vast selection of each to best conform to the needs of the end use. Huge macro molecules of highly ordered PVC pack and interlock to form a rigid polymer. Properly chosen plasticizers lead to flexible floor coverings useful in anti-fatigue mats and launderable, walk off mats.

Description

COMPOSITIONS OF POLYVINYL CHLORIDE, USEFUL AS FLOOR COATINGS TECHNICAL FIELD This invention relates to floor coatings and molded resilient films of solids and foamed polyvinyl chloride (PVC) films.

PREVIOUS TECHNIQUE Molded and foamed films of flexible vinyl chloride (PVC) solids, in various thicknesses, are used for many applications; particularly in the field of floor coverings. Most notably, they have been found in the mats industry for cleaning shoe soles, the fatigue mats industry and the carpet backing industry. Being a true thermoplastic material, PVC is characterized by memory and slow recovery from deformations, as opposed to true interlaced polymers, such as natural rubber and certain polyurethanes. The ease of process, the chemical and environmental tolerances, the versatility of properties and the relative favorable economy, make the PVC a selection material where possible.

Mats for Cleaning the Soles of Shoes Mats for cleaning the soles of shoes are the types of products found in the entrances of doors, in order to remove dirt-like material from the soles of shoes. Many of them are washed periodically and reused. The mat is a padded carpet module of various sizes, molded in a vinyl backing material or embedded in a layer of various types of rubber backs. After subjecting the mat to an adequate amount of heat, necessary to cure the backing, the product is trimmed leaving an edge of rubber or PVC on all sides of the final mat. Until now rubber-backed mats have withstood the heat and tumbling action of laundry processes, better than conventional mats with PVC backing. Conventional PVC mats soften with heat and stretch easily by distorting the edges. These edges stretch beyond their capacity for recovery and end up "curling". In all other aspects, conventional PVC mats are superior to commercial rubber mats products at this time. Anti Fatigue Mats Fatigue mats are foamed polymer pads, which generally vary in thickness from 6.35 to 19.05 mm. The purpose of these mats is to absorb biomechanically much of the stresses of the anatomical joints of the body and extremities and return the energy, as efficiently as possible, to these parts of the body, reducing the contribution that the human body has to make to lift the feet of the floor. Since the impact force is greater and the impact time is shorter, an elastic mat that recovers the deformation will quickly provide a much greater lifting force than an inactive, non-resilient, slow recovery mat. In general, rubber foam is elastic; more resilient than conventional PVC foam. In addition, the mat or cushion recovers, substantially instantaneously, the deformation that results in the mat, which is easy to reabsorb additional impact energy.

EXPOSITION OF THE INVENTION The compositions of this invention encompass the products obtained from flexible plasticized PVC, usually formulated as a dispersion of high molecular weight PVC resin, in a special mixture of plasticizers. Both PVC resins and plasticizers are chosen from a vast selection of each, to better meet the needs of the final use. The huge macro molecules of highly ordered PVC are packed and locked internally to form a rigid polymer. The plasticizers, chosen appropriately, will form a stable orientation by virtue of the complex geometry of both the PVC and the plasticizer. The invention makes PVC comparative to natural rubber in resilience and elasticity, while still improving the superiority of PVC in many accepted areas of mechanical and chemical properties. While the literature describes small differences in resilience by the use of certain plasticizers, this invention goes beyond known or disclosed published information, by altering PVC to approximate elasticity to natural rubber. The normal plasticizers used for PVC are generally of the following construction: The "R", in this case, are generally an alkyl group, linear or branched, with 6 to 11 carbon atoms. The PVC resins of this invention are homopolymers having huge macro molecules of vinyl chloride repeating units: (-H2CCHCL-) n, where n is an integer ranging from about 1000 to 2500. The PVC resins of this invention have a K value of at least 75 and preferably ranges from 75 to 100. Molecular weight, as used throughout this specification, means the weight average molecular weight. The "K value" is a universal measure of molecular weight. K values above 75 are considered high; K values below 65 are considered low.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a cross-sectional view of a mat for cleaning shoe soles, according to the invention; and Figure 2 is a cross-sectional view of a fatigue mat, according to the invention.

BEST MODE FOR CARRYING OUT THE INVENTION Figure 1 shows a mat 10 for cleaning shoe soles, comprising a padded fibrous yarn or carpet 12 and a cushioned backing layer 14, which are embedded in a flexible PVC film of the invention, shown as the substrate 16. This substrate 16 is larger than the carpet 12 and the backing 14 and forms the edges 18 around them.

The fibrous material and the yarns used as the yarn or carpet 12 may comprise synthetic, natural fibers or a combination of synthetic and natural fibers, such as, but not limited to, polyamides such as nylon, olefins such as polypropylene, wool and blends. of wool, acrylic threads, mixtures of acrylic and nylon, and polyesters, and their combinations and mixtures. The carpet 12 requires a backing layer 14, in which the tufts of the thread are embedded. In the case of a quilted type carpet, this is commonly a canvas or non-woven type material, comprised of glass fibers, polyester fibers, polypropylene, jute, nylons, acrylics or combinations of fibers. The carpet 12 can also be embedded in a resinous layer of a variety of polymers, such as, but not limited to, PVC, polypropylene and bituminous layers. Layer 16 is usually a heavy layer of PVC or natural or synthetic rubber, which holds the mat down and protects this floor mat and protects the floor of the floor from above. In the case of esterase with PVC backing, the formulation is basically composed of a phthalate plasticizer, such as the DOP, a PVC resin of unspecified molecular weight and many of the inexpensive, inert fillers, generally, but not limited to , calcium carbonate, as the application will be tolerated.

Figure 2 shows the fatigue mat of this invention as the substrate 20. According to the invention, we have found that by replacing all or part of the plasticizer with a less aromatic molecule, such as an adipate structure, the resilience of the PVC We have found that by coupling this with a high molecular weight PVC, we will increase the resilience more. By treating this system for a period of time at temperatures between 54 and 71 SC, resilience is further enhanced. The adipate structures are a plasticizer construction of dibasic aliphatic acids, which have the formula: O O II II R - O - C - C C - C - C - O - R The "R", in this case, are alkyl groups, linear or branched, having 6 to 11 carbon atoms. The structure of this molecule allows the closest proximity of the polar sites of the plasticizer to the polar sites of the corresponding PVC resin. Examples of ethers of dibasic aliphatic acids include dioctyl adipate, diisodecyl adipate, dioctyl azelate and dioctyl sebacate. Tempering stabilizes this orientation.

Examples of italic diesters include esters of phthalic acid with one or two C4 to C12 alcohols, for example dioctyl phthalate, diisooctyl phthalate, diisononyl phthalate, diisodecyl phthalate, diisoundecyl phthalate, butyl-benzyl phthalate and octyl-benzyl phthalate. The molecular weight of plasticizers varies from 300 to 500 in most cases. Molecular weight, as used herein, means the weight average molecular weight. We have found that varying the ratio of aliphatic to aromatic plasticizers and using a high molecular weight PVC, we can move away from the normal resilience of PVC to and throughout the route, to the resilience of natural rubber. We have found that for foam constructions in the density of 320 to 480 kilograms per cubic meter, a resilience range of 10 to 45 is achieved in the ASTM D2632 resilimeter. The vertical rebounds for the foamed natural rubber measured between 40 and 45 on the scale of the instrument. Conventional PVC with the following general foam formulation will generally measure in the range of 6 to 10. PVC (K-values from 65 to 70) Homopolymer 100 parts Dioctyl Phthalate (DOP) 60-100 parts Dicarbonamide Blowing Agent AZO 3 parts We replace 50 to 100% of the DOP plasticizer with the DOA plasticizer (adipate), the resilience will increase from 10 to 20 on the scale if we increase the molecular weight of the PVC resin from about 60 to 80 (K value). Resiliences greater than 35 are easily obtained. If we temper the system, the resiliences of 40 or better will result. The so-called anti-fatigue mats, produced at this time, are samples of products that are greatly improved by this invention. Our invention produces a PVC foam equal in resilience to rubber, as measured by the resilience of ASTM D2632 by the vertical rebound test. The PVC foams of this invention can be manufactured by mixing a powder and a liquid mixture comprising the thermoplastic polymer, plasticizer fillers, blowing agents or foaming agents and additives on a substrate or conveyor belt. The powder mixture can then be smoothed between smoothing rollers and foamed and melted at a temperature within the foam range of about 120 to 2002C. The floor coverings can be manufactured in a width of approximately 2 to 5 meters, using the commercially available process equipment.

EXAMPLE I Anti Fatigue Mats The formula for the anti fatigue mat is as follows: Oxi 80 HC - High Molecular Weight - PVC 30-100 parts Homopolymer or PVC Copolymer of Molecular Weight Medium 0-30 parts Octyl Adipate DOP / Di - Plasticizing Mixture 100 parts AZO Dl-carbonamide- Blowing Agent 3 parts Zinc Octoate at 15% - Blowing promoter 2 parts Calcium Carbonate - 25-part filling The invention recognizes that replacing all or part of the plasticizer with an adipate-based plasticizer and replacing all or part of the resin with a high-weight resin molecular, with a K value greater than 75, we will move from the properties of regular PVC to the resilience of the rubber. This invention also includes improving the resilience by post-tempering the molded and cured product. The above formula will produce a PVC foam with a density of 480 kilograms per cubic meter. After 30 minutes - tempered at 65.5SC, this foam will measure (ASTM D2632) about three to five times the vertical rebound resilience to the normal fatigue mats common in the industry. This foam outperforms natural latex rubber foam and is equivalent to ground rubber foam. While the numbers given apply to a typical fatigue mat found in the field, similar movement up and down the elasticity scale and resilience also applies to films of varying thickness covering density ranges of 1280 to 128 kilograms per cubic meter. Such products are also manufactured by mechanically foaming the formulation. The use of a silicone surfactant, such as Dow Corning DC.11250, in place of or in conjunction with a chemical blowing agent, such as, but not limited to, AZO dicarbonamide. Hydrazine-based blowing agents are also commonly used. This invention also allows us to obtain a superior, washable, "shoe sole cleaning" mat described as follows. Cleaning mats are carpet-like products found at door entrances in order to remove dirt-like material from shoe soles when entering a building. Many of them are washed periodically and reused. According to the invention, the mat includes a padding carpet module of variable size, molded in a thick layer of special polyvinyl chloride plastisol (mixture of polyvinyl chloride resin dispersed in a liquid plasticizer). After submitting the PVC to an adequate amount of heat, necessary to melt this PVC into a thermoplastic flexible layer, the product is trimmed leaving a PVC border on all sides of the final mat. The finished product is either heated for 30 minutes in an oven or left for 30 minutes in 65.52C water, before turning and cleaning. The PVC resin may contain some minor molecular resins, copolymers or the so-called mixing resins of large particle size, but the preponderance of the PVC resin has to be above 77 at the "K" value. According to this invention, the durability of the vinyl is markedly improved as the proportion of resins with a K value greater than 75 is increased. The plasticizer should be in the range of "70" to "100" parts per hundred parts of resin (PHR of PVC). The fill level must be between "0" and "50" PHR. Tempering is best achieved between 62.7 and 68.332C for 20-30 minutes, higher temperatures are not good and lower temperatures do not work. The thickness of the vinyl is preferably in the range of 1778 to 2032 microns, with densities between 800 and 1440 kg / m3. It may be possible to include some foaming in certain applications. The carpet can be backed by foam or laminated to a foam for cushioning or for anti-fatigue purposes as well.

EXAMPLE II Cleansing Mat for Shoes Sole A formula for a washable / tempered mat is as follows: Oxi 80 HC - high molecular weight PVC 100 parts (K-value of 80) DOP / DOA blend 80-100 parts Calcium Carbonate Filler 0-50 parts Color as needed.

The carpet - nylon padded on a non-woven polyester backing. Any fiber that resists the 1902C can be used on the front and backrest. The process to 1902C tending a layer of 1778 microns of PVC on which the carpet is placed and melted and melted together in a band furnace.

EXAMPLE III Cleaning mats of the sole of the shoes, according to the prior art A normal mat with PVC backing varies in the formulation, depending on the front fibers used, as well as the primary backing material in which the yarn is quilted . If any of them contains olefin fibers, then a typical formulation for PVC would be this: Parts Copolymer of 4% acetate dispersion type 50-100 Oxi 675 Mixed resin of large particle size 0-50 DOP Di-Octyl plasticizer - Ftalato 60-90 Calcium Carbonate Filling 50-200 Color 1-2 PVC resins and plasticizers were selected to produce the optimum balance of economy and properties for a layer of molten PVC in the range of 143 to 154 ° .c.

EXAMPLE IV Prior Art Sole Sole Cleaning Mat Many mats are made with nylon or polyester threads, padded on polyester backings or polyester / nylon (or other non-olefinic) blends, to allow for process temperatures. of the larger furnace for better PVC firmness, as measured by tension and tear tests. A formulation for a mat of this type is as follows: Parts Homopolymer PVC Oxi 6337 50-100 Mixture of Homopolymers Oxi 567 0-50 Plasticizer DOP (dioctyl phthalate) 60-90 Filler Calcium carbonate 50-200 Color 1-2 Our invention produced a vinyl mat that has increased resilience and greater durability than rubber mats in the current market and that resists the forces involved in commercial laundries, which have so far "curled" the edges of backed mats of PVC common in commerce. While we do not ignore other applications, we have used the areas of shoe cleaning mats, washables, and fatigue mats to illustrate the many applications of this invention. Many areas of use are known where the superior general properties of PVC increased by the elastic nature of rubber are valuable. A few of these are sports surfaces, aerobic mats, special industrial packaging, carpet supports, commercial carpets with foamed backs, carpet slabs with foamed backs, and resilient floors with foamed backs.

Claims (16)

1. CLAIMS 1. A composition comprising at least one homopolymer, of high molecular weight, of a polyvinyl chloride resin, and at least one plasticizer of aliphatic dibasic acid.
2. 2. A composition, according to claim 1, wherein the PVC resin is represented by the formula: (-H2CCHCl-) n where n is an integer ranging from about 1000 to 2500.
3. 3. A composition, according to with claim 1, wherein this composition has been tempered at a temperature ranging from 54 to 7 csc, for a time ranging from about 20 to 30 minutes.
4. 4. A composition, according to claim 1, wherein said composition includes at least one phthalic diester plasticizer.
5. 5. A composition, according to claim 1, wherein the homopolymer has a K value of at least 75.
6. 6. A composition, according to claim 1, wherein the homopolymer has a K value ranging from 75 to 100.
7. 7. A composition, according to claim 1, wherein the homopolymer is obtained from large macro molecules.
8. 8. A composition, according to claim 4, wherein the composition is a mixture of PVC homopolymers and PVC copolymers.
9. 9. A composition, according to claim 4, wherein the phthalic plasticizer is obtained from at least one C4 to C1 alcohol
10. 10. A composition, according to claim 1, wherein the aliphatic plasticizer is represented by the formula: 0 0 II II R - O- C C - C - C - C C - O - R wherein R is an alkyl group, linear or branched, having from 6 to 12 carbon atoms.
11. 11. A composition, according to claim 1, wherein the aliphatic plasticizer is an adipate plasticizer.
12. 12. A composition, according to claim 4, which comprises: 100 parts by weight of PVC resin and 70 to 100 parts by weight of plasticizer, per 100 parts of PVC resin, in which at least 50 weight percent The plasticizer is an aliphatic plasticizer.
13. 13. A composition, according to claim 12, wherein 50 to 80 weight percent of the plasticizer is an aliphatic plasticizer.
14. 14. A floor covering layer, which comprises the composition of claim 1.
15. 15. A foam cushion against fatigue, comprising the foamed composition of claim 1.
16. 16. A composition comprising at least one homopolymer, of high molecular weight, of a polyvinyl chloride resin, at least one phthalic diester plasticizer and at least one plasticizer of a dibasic aliphatic acid, in which this composition has been tempered at a temperature which varies from 54 to 71SC, for a time that varies from 20 to 30 minutes.