CS201796B1 - Thermoplastic mixture for manufacturing hoses and other products - Google Patents

Description

The invention relates to the composition of a thermoplastic composition for the manufacture of hoses and other rubber products.

German Patent Specifications 2 202 706 and 2 202 738 disclose a method and a principle for the preparation of thermoplastic mixtures by so-called dynamic vulcanization in high-speed machines. Partial dynamic vulcanization of EPM and EPDM in the presence of polyethylene or polypropylene is described.

Thermoplastic compositions containing fully crosslinked rubber cannot be produced on commercially available and commercially available kneading machines according to the above mentioned documents. The manufactured product is irreversibly cross-linked and cannot be processed on plastic and rubber machines.

These drawbacks are overcome by the subject of the invention, which is a thermoplastic composition for the manufacture of hoses and other products, characterized in that it contains 15 to 60% by weight of vulcanized ethylene-propylene terpolymer or diene rubber, in which diene can be copolymerized with styrene or acrylohitrile; % by weight of polyethylene or isotactic polypropylene, 1.0 to 14.9% by weight of a solid plasticizer having a softening point of 30 to 140 ° C and 10 to 50% by weight of reinforcing fillers.

An important component of the blend that allows dynamic vulcanization to be carried out in operating kneading machines is the presence of a solid plasticizer, which may be asphalt or natural resin, coumarone-indene resin, aromatic and aliphatic resins, rosin derivatives, polyterpene resins. Addition of a larger amount of solid plasticizer has an adverse effect on some properties of the resulting compositions, for example, decreases resistance to permanent deformation. It has been discovered that a composition characterized by high mechanical properties and a low value of permanent deformation and elongation that can be easily produced on conventional kneading machines can be prepared even in the presence of a small amount of solid plasticizer. The transparent solid resin preparation can be advantageously used in light or color mixtures.

In order to modify the properties, the mixtures can be filled with inorganic fillers, plasticizers or substances which facilitate processing such as factis, paraffin and the like.

Addition of stabilizing agents is possible to increase the resistance of the compositions to oxidation and ozone.

The hot mixed mixture can be further processed on a heated twin-roll into strips from which pellets are extruded or can be processed into film on roller machines, or it can be processed on injection molding machines, or it can be shaped by a vacuum. The mixture can be used for the production of hoses, cable sheathing, insulation foils, etc.

Example 1

In a 60-liter Banbury-Bridge high-pressure kneading machine, the thermoplastic composition of formula 1 was blended. . After 2 minutes of kneading, the temperature of the mixtures reached 120 ° C, at which point an accelerator was added. Within 2 minutes the power take-off was increased by 10%. After stirring for 8 minutes, the temperature of the mixture reached 160 ° C and the contents of the chamber were discharged onto two 130 ° C cylinders, the mixture was rolled into a strip from which the test specimens were punched out after cooling and the properties determined.

Recipe used 1 parts by weight of butadiene-styrene rubber 100 polyethylene 100 coumarone-indene resin 15 kaolin 80 paraffin 1 zinc oxide 5 stearic acid / 2 zinc diethyldithiocarbamate _f 2 sulfur [2] mechanical properties of the mixture tensile strength, MPa 9.3 elongation,% 180 elasticity,% 18 Shore A hardness 70 elongation,% 25 Crescent tensile strength at 25 ° C, N / mm 30 permanent deformation in clock pressure, 23 ° C,% 24.6

Example 2

The mixing procedure is the same as in Example 1. Asphalt was used in place of the coumaronindene resin.

Claims (4)

SUBJECT Thermoplastic composition for the manufacture of hoses and other products, characterized in that it contains 15 to 60% by weight of vulcanized ethylene-propylene terpolymer or diene rubber in which the diene can be copolymerized with styrene or acrylonitrile, 5 to 50% by weight of polyethylene or isotactic polypropylene, 1.0 to 14.9% by weight of a solid plasticizer having a softening point of 30 to 140 ° C and 10 to 50% by weight of reinforcing fillers. 2. The thermoplastic composition of item 1, wherein the recipe used is 2 parts by weight of acrylonitrile butadiene rubber. 30% by weight acrylonitrile 100 polypropylene 50 carbon black 100 asphalt -30 fact 10 dibutyl phthalate 20 antioxidant / 1 zinc oxide 5 stearic acid and tetramethylthiurammonosulfide 1.5 2-bis benzothiazolyldisulfide 0.5 sulfur / 2 mechanical properties of the mixture tensile strength, MPa 6.0 ductility,% 220 elasticity,% 20 Shore A 75 hardness,% .............. ....... 20 structural strength Crescent at 23 ° C, N / mm 28 permanent compressive deformation, 22 hours, 23 ° C,% 18.6 Example 3 The mixing procedure is the same as in Example 1. The 2 weight recipe used is used - parts ethylene-propylene terpolymer 100 polyethylene 30 carbon black 140 asphalt 40 mineral oil 20 stearic acid> 1,5 zinc oxide (5 tetramethylthiurammonosulfide 1 sulfur 0,8 mechanical properties of the mixture tensile strength, MPa 8.5 elongation,% 300 elasticity,% 23 Shore A 78 hardness,% 40 Crescent structural strength at 23 ° C, N / mm 32 permanent compressive deformation, 22 h at 23 ° C,% 35 BACKGROUND OF THE INVENTION comprising as a solid plasticizer asphalt, natural resin fractions, coumarone-indene resins, aromatic resins, aliphatic resins, polyterpene resins, rosin derivatives, or combinations thereof. 3. A thermoplastic composition as claimed in claim 1, comprising from 1 to 20% by weight of a mineral oil or dicarboxylic acid ester. 4. The thermoplastic composition of claims 1, 2 and 3 comprising from 1 to 30% by weight of fact.