Plastic modifiers containing natural rubber, plastic molded articles and their use

Abstract

To provide a plastic modifier including natural rubber, a plastic molded article and use of the same.SOLUTION: A plastic modifier is provided, formed of a polymer composition which includes 10-35 wt.% of natural, non-vulcanized rubber; 10-70 wt.% of an ethylene-vinyl acetate copolymer (VA content of 19%); and 10-70 wt.% of an ethylene-vinyl acetate copolymer (VA content of 28%). The modifier further includes 1-5 wt.% of a homogenizing agent, 1-5 wt.% of a flow auxiliary agent, 1-15 wt.% of a silicon dioxide-reinforcing filler and up to 15 wt.% of a talc mineral filler, up to 15 wt.% of a calcium carbonate mineral filler, and up to 15 wt.% of a paraffinic plasticizer, in the composition. A plastic molded article including the modifier, and use of the same are also provided. The modifier enables use of a compound which can generally promote recycling of plastic, and has energy economical efficiency and is sustainable.SELECTED DRAWING: None

Description

[Technical Field]

[0001] FIELD OF THE INVENTION The present invention relates to plastic modifiers, generally formed from polymer compositions containing natural rubber prepared with olefins, and recycled plastics containing the modifiers, which can restore and improve the physical and mechanical properties of virgin and recycled plastics. [Background technology]

[0002] Fundamentals of the invention In general, various additives and modifiers for plastics and polymer compositions are known in the art. These modifiers and additives have various functions and are subdivided into categories according to their functions and properties. Thus, the following are additives and modifiers: stabilizers, plasticizers, lubricants, impact modifiers, flame retardants, nucleating agents, etc.

[0003] In this way, the additives and modifiers can adapt the same polymer for different purposes and provide different uses for the final composition containing the modifier.

[0004] In general, modifiers must exhibit several technically feasible properties, such as efficiency in the function to be performed, stability under processing and operating conditions, easy dispersion without migration to the polymer surface, non-toxicity, low cost, and not impairing the properties and characteristics of the polymer.

[0005] Generally, additives are added for two main reasons: the need to modify the physical and mechanical properties of the material, or the need to give the polymer greater stability, whether during processing or operation.

[0006] The more commonly used modifiers in this field are nitrile rubber (NBR) and EPDM (ethylene propylene diene rubber). In this regard, nitrile rubber (NBR) has excellent oil and abrasion resistance. Blending with low-unsaturation rubbers, such as ethylene-propylene-diene terpolymer (EPDM) and butyl rubber (IIR), is an attractive method for developing new materials that are more resistant to the effects of heat, oxygen, and ozone. However, the physical properties of such blends are generally lower than would be predicted from the properties of the individual elastomers, primarily due to differences in polarity and unsaturation content of the constituent components.

[0007] Such modifier options are composed of materials and are exclusively by synthetic means, requiring, for example, the use of solvents in their manufacture and production, and are therefore disadvantageous from an environmental point of view. Summary of the Invention

[0008] Goal of the invention One object of the present invention is to provide a plastic modifier formed from a polymer composition containing natural rubber (NR).

[0009] Another object of the present invention is to provide a plastic modifier that, when properly added, allows for the recycling of plastics of different types and origins and can restore or provide improved physical and mechanical properties.

[0010] It is also an object of the present invention to provide a sustainable plastic modifier that includes natural rubber in its composition.

[0011] It is yet another object of the present invention to provide a plastic modifier that can be added to any plastic to enable an injection molding process in a conventional thermoplastic injection molding machine or an extrusion molding process in a conventional thermoplastic extruder.

[0012] It is yet another object of the present invention to provide a plastic modifier that provides plastics with increased modulus, flexural and tensile strength, abrasion resistance, chemical resistance, low temperature resistance, and an improved rubberized appearance.

[0013] Another object of the present invention is to provide a plastic modifier that gives recycled plastics properties similar to virgin plastics, with memory capacity and high resilience.

[0014] Brief description of the invention The present invention relates to a natural rubber-containing plastic modifier formed from a polymer composition containing 10-35 wt% unvulcanized natural rubber (NR), 5-35 wt% ethylene-alpha-olefin copolymer, 10-70 wt% ethylene-vinyl acetate copolymer (VA 19%), and 10-70 wt% ethylene-vinyl acetate copolymer (VA 28%). The modifier also contains 1-5 wt% homogenizing agent, 1-5 wt% flow aid, 1-15 wt% silicon dioxide reinforcing agent, up to 15 wt% talc mineral filler, up to 15 wt% calcium carbonate mineral filler, and 1-25 wt% paraffinic plasticizer.

[0015] The modifier preferably comprises 1 / 3 by weight of unvulcanized natural rubber (NR) relative to the modifier composition. qualifier.

[0016] As for the homogenizing agent, HOMOGETEC is preferably used, followed by FLUXTEC 32 as a preferred flow aid.

[0017] The above-mentioned modifier is added to a plastic preferably selected from polypropylene (PP), polyethylene (PE), ABS, polyethylene terephthalate (PET) and polystyrene (PS) in a proportion of 3 to 50% by volume of the final plastic composition containing the modifier.

[0018] Another object of the present invention is a plastic molded article containing the plastic modifier of the present invention in an amount of 3 to 50% by volume of the final plastic composition.

[0019] Furthermore, the object of the present invention is to use a modifier that is added to the plastic in a proportion of 3 to 50% by volume of the final plastic composition containing the modifier. DETAILED DESCRIPTION OF THE INVENTION

[0020] Detailed Description of the Invention The present invention relates to a plastic modifier formed from a polymeric composition that can provide significant improvements in impact resistance, flexibility, elongation, and low temperature resistance, as well as improved memory capacity and high strength to the plastics to which it is added.

[0021] In this sense, the plastic modifier generally allows for the modification of plastics and can be used as an additive in plastics or raw plastics such as polypropylene (PP), polyethylene (PE), ABS, polyethylene terephthalate (PET), polystyrene (PS) and other plastics.

[0022] Naturally, depending on the amount of modifier used, the plastics will have differentiated properties and characteristics, the modification being inherently related to the percentage of modifier incorporated into any given plastic.

[0023] The plastic modifier of the present invention is formed from a polymer composition containing a natural rubber containing an olefin, among other things. The modifier is prepared by preparing a rubber containing an olefin by further incorporating a resinous compatibilizer and a flow aid with the natural rubber and olefin to form the base composition of the plastic modifier of the present invention.

[0024] Unlike plastic modifiers commonly used in the industry, such as nitrile rubber (NBR) and EPDM (ethylene propylene diene rubber), the plastic modifier of the present invention contains natural rubber in its composition, making it a renewable and sustainable modifier, with green and ecological appeal.

[0025] In this way, reducing the need for use of raw materials results in a reduction in the overall pollution chain involved in the production of raw plastic resins.

[0026] In view of the above considerations, the plastic modifier is formed from a polymer composition comprising 10-35 wt% unvulcanized natural rubber, 5-35 wt% ethylene-alpha-olefin copolymer, 10-70 wt% ethylene-vinyl acetate copolymer (VA content 19%), 10-70 wt% ethylene-vinyl acetate copolymer (VA content 28%), 1-5 wt% homogenizing agent, 1-5 wt% flow aid, 1-15 wt% silicon dioxide reinforcing filler, up to 15 wt% talc mineral filler, up to 15 wt% calcium carbonate mineral filler, and up to 15 wt% paraffin plasticizer.

[0027] Although various flow aids and homogenizing agents can be used, it is preferred to use the ingredient FLUXTEC 32 as a flow aid manufactured and sold by Proquitec Industrial, Distributors and Agents, and similarly it is preferred to use the ingredient HOMOGETEC MTC as a homogenizing agent manufactured and sold by Proquitec.

[0028] With respect to the ethylene-olefin-olefin copolymer, preferably said copolymer is selected from either TAFMER and ENGAGE (commercially known).

[0029] The unvulcanized natural rubber used in the range of 10% to 35% by weight may be any of various grades of natural rubber, such as Type 3L, GEB, Pale Crepe, SMR, etc. The addition of natural rubber to the composition imparts rubber elasticity, resilience, resilience, grip (adhesion to the substrate), and wear properties.

[0030] Preferably, the natural rubber represents one-third by weight of all components forming the plastic modifier according to the present invention.

[0031] Having described the composition of the plastic modifier of the present invention, the physical and mechanical properties of the modifier are presented below. [Table 1]

[0032] Thus, the plastic modifier of the present invention is added to a plastic so as to constitute 3 to 50 weight percent of the total composition of the plastic and modifier, depending on the properties desired to be imparted to the plastic and the type of plastic to which the modifier is added.

[0033] The addition of high percentages (greater than 50% by weight) of such plastic modifiers allows the plastic to be recycled more times without the properties of the plastic, such as stretchability, being lost in the recycling process.

[0034] The addition of the plastic modifier of the present invention to plastics allows for the recycling of plastics with altered physical and mechanical properties. In this regard, in addition to the changes in properties already described, the presence of the modifier in the plastic leads to energy economies, since plastics containing the modifier of the present invention can be injected at lower injection temperatures than conventional plastics without the modifier.

[0035] Furthermore, the addition of the modifier of the present invention imparts a rubber-like appearance and a better finish to molded plastic articles made from conventional plastic compositions containing the modifier.

[0036] Furthermore, because natural rubber has long carbon chains, which change the nature and properties of the material, the use of additives can make hard plastics and those prone to breaking very flexible and rubber-like.

[0037] Furthermore, the presence of natural rubber gives the plastic excellent flexibility under use conditions down to -40°C, so when combined with the modifier of the present invention, the low temperature resistance of the plastic is significantly improved. [Example]

[0038] Among the exemplary examples of uses and applications of the plastic modifier according to the invention, the examples detailed below can be considered.

[0039] Example 1 50% by weight of the modifier of the present invention was added to 50% by weight of polypropylene (PP). This composition can be used to produce high-rigidity, high-flexibility plastic molded products using conventional thermoplastic injection molding techniques, replacing polyamide (PA) 66 / nylon 66 in many applications (processing applications up to 130°C). In addition to cost reduction, this composition allows for a significant reduction in injection temperature, as polyamide 66 is injected at temperatures above 260°C and requires hydrogenation to increase flexibility. The combination of 50% by weight of polypropylene and 50% by weight of the modifier eliminates the need for a hydrogenation step, allowing for a reduction in injection temperature to 190°C.

[0040] From the extrusion of this final composition the following can be obtained: bushings, connections, seals, engineering plastics, connectors, circuit breakers.

[0041] Example 2 The modifiers of the present invention are added to polypropylene at up to 30% by volume and can be molded using standard thermoplastic injection molding processes into plastic articles such as: chairs, bumpers, boxes, cases, packaging, lids, tables, pallets, frames, flooring, engineering plastics, connectors, tubing, and general plastics.

[0042] Example 3 Modifiers added to polypropylene at up to 5% by volume showed increases in stretchability of 50% to 100% in tests carried out according to the usual standards described in this report.

[0043] By increasing the amount from 5% to 10% by volume, a change in elongation from 50% to 125% was measured, and a decrease in hardness was also observed in the range above 5% modifier.

[0044] Example 4 When added to polyethylene plastics in amounts of up to 30% by volume, the modifier is used to make pallets, toilet sheets, helmets, packaging, lids, protective gear, toys, industrial boxes, and general plastics.

[0045] Example 5 Up to 30% by volume of modifiers added to polystyrene (PS) plastics are used to make coatings, combs, hangers, circuit breakers, trays, and general plastics.

[0046] Example 6 Up to 30% by volume of modifiers added to ABS resin can result in furniture, household appliances, handrails, panels, helmets, electronics, motorcycle fairings, and general plastics.

[0047] While preferred embodiments of the present invention have been described, it should be understood that the scope of the present invention encompasses other possible variations of the inventive concept described and is limited only by the content of the claims, including possible equivalents therein.

Claims

1. 1. A plastic modifier containing natural rubber, characterized in that it is formed from a polymer composition comprising: 10 to 35 wt. % unvulcanized natural rubber; 5 to 25 wt. % of an alpha-olefin ethylene copolymer; 10-70 wt. % ethylene vinyl acetate copolymer having a VA content of 19%; 10-70 wt. % ethylene vinyl acetate copolymer having a VA content of 28%; wherein the plastic modifier is added to the plastic in a proportion that accounts for 3 to 50% by volume of the final plastic composition containing the plastic modifier.

2. A modifier as described in claim 1, characterized in that it contains one-third unvulcanized natural rubber by weight relative to the modifier.

3. The modifier according to claim 1, further comprising 1 to 5% by weight of a homogenizing agent.

4. The modifier according to claim 1, further comprising 1 to 5 wt % of a flow aid.

5. 2. The modifier of claim 1, further comprising 1 to 15% by weight of a reinforcing filler of silicon dioxide.

6. 2. The modifier of claim 1, further comprising up to 15% by weight of a mineral filler of talc.

7. 2. The modifier of claim 1, further comprising up to 15% by weight of a mineral filler of calcium carbonate.

8. The modifier according to claim 1, further comprising 1 to 25% by weight of a paraffin-based plasticizer.

9. 2. The modifier of claim 1, wherein the plastic is one of polypropylene (PP), polyethylene (PE), ABS, polyethylene terephthalate (PET), and polystyrene (PS).

10. Use of the plastic modifier according to any one of claims 1 to 9, characterized in that it is added to plastics in an amount of 3 to 50% by volume relative to the final plastic composition containing the modifier.

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