CS239153B1 - Launched the PVC <i> PVC Leak by Dovalena! tangential tension sigma 12.5 MPa - Google Patents

Abstract

The purpose of the invention is a method of producing pressure pipes with a permissible tangential stress sigma of 12.5 MPa. The stated purpose is achieved by combining two stabilizers based on basic lead sulfates with different contents of other components, namely lead and calcium stearates and lubricants. The mixture with such a modification of the lubricating and stabilizing system can be processed on twin-screw extruders of various designs, while the pipes produced at the same time have a high permissible tangential stress. The invention can be used in the plastics industry when processing hard PVC mixtures.

Description

239133

The invention relates to a process for the production of PVC pressurized tubes with a sigma 12,5 MP-tangential tangential footprint, and to a spit-type screw extruder.

According to the prior art processes for the production of pressure tubes, in particular tubes with a higher tangential stress on the modern twin screw extruders with parallel or conical thread lengths of over 20 D, a PVC mixture is used, where a complex baseol stabilizer in the form of a stabilizing and lubricating system is used tribasic and / or tetrabasic lead sulphate with the addition of neutral and / or dibasic aluminum stearate, calcium stearate and lubricants, preferably paraffins and / or stearic acid having a lead content of preferably 42.0% by weight. and a calcium content of preferably 0.58%.

This complex stabilizer is dosed in the range of 1.8 to 2.6 wt. preferably 2.2 wt. parts per 100 parts by weight of polyvinyl chloride.

A disadvantage of this process is that the polyvinyl chloride mixture of this and the higher content of the stabilizer stabilizer of this composition can be processed in extrusion double-walled machines of different construction. Therefore, a lubricant in the form of paraffins and / or acids is added to the complex stabilizer of said composition. stearic in the dio 0, 5 wt. with a lower content of calcium stearate and a higher content of lubricants, preferably paraffinic or stearic acid with a total lead content of preferably 40.6% by weight. and dispensing 2.5 to 3.5 wt. parts with an advantage of 2.8 wt. parts per 100 wt. polyvinyl chloride.

A disadvantage of this process is the reduction of the pipe endurance against the internal overpressure, so that the prescribed rupture time of one hour is not achieved at a pressure test at 20 ° C and t-angular sigma strain of 46 MPa and above.

These drawbacks are obviated by the process of producing a PVC pressure tube with a permissible tangential tension of 12.5 MPa, the principle of which is to prepare a mixture of PVCs by combining a complex stabilizer comprising a tribasic and / or tetrabasic lead sulphate containing an ineutral and adiphasic lead stearate, stearate calcium, and lubricant, preferably paraffinic or stearic acid, with a total lead content of preferably 42.0% by weight. and the calcium content is preferably 0.58 wt. in dispensing the dio mixture of PVC with 0.2 to 2.8 wt. preferably from 1.9 to 2.2 wt. parts per 100hmot. parts of PVC, together with a complex stabilizer of this composition, a lower content of calcium stearate and a higher content of preferably paraffins and / or stearic acid, with a total lead content of 40.6% by weight. in a feed to a PVC mixture of 0.2 to 2.8 wt. parts preferably 0.9 to 0.6 wt. parts per 100 wt. parts of PVC so that the total content of both complex stabilizers in the PVC blends is 1.8 to 3.0 parts by weight, preferably 2.4 to 2.8% by weight of the parts. die-hunting per 100 wt. PVC parts. The advantage of this is that it achieves a new effect which allows the PVC mixture to be worked on extruders at the same time and to achieve the quality of the PVC sigma tubes of 12.5 MPa prescribed by the standard. Přikladl

PVC mixtures were prepared on a fluidized mixer containing a complex tri-base lead stabilizer containing a neutral and dibasic lead stearate, calcium stearate, and baseparaffin and stearic acid total stabilizer in the stabilizer 42 as a stabilizing and lubricating system. %, 0 wt. and calcium-0.5% -8% by weight. at a dosage of 2.2 parts by weight, 2.4% by weight; parts, 2.6 wt. parts and 2.75 wt. parts per 100 wt. PVC parts.

The mixture containing the 2.75 wt.% Stabilizer has a final lead content of 1.12 wt.%, Which is equal to the arithmetic ratio of the lead content of the stabilizer containing 40.6 wt%. and in a stabilizer containing 42.0 wt. at 1: 1 dosing. These compositions were not usable on twin-cone extruders, since PVC degradation occurred. Example 2

From the PVC mixture containing as a stabilizing and lubricating system the complex alcohol stabilizer in Example 1, supplemented with 0.3 parts by weight of stearic acid as a lubricant to 100 wt. PVC parts were extruded, on two-tube extruders with parallel and conical worms of 0 110 XX 4.3 mm. Despite the total content of the mixture with the dosage of 2.75 wt. the die-hunting reached 1.12 wt. as in example 4a 6, the pipes did not meet the prescribed pressure test at a temperature of 20 ° C and the tangential base 46 and 48 MfPa, as they burst at the time of the hour. Example 3

Mixtures containing a complex tribasic sulfate-based stabilizer were prepared on a fluid mixer as a lubricating and stabilizing system. lead with addition of neutral and dibasic lead stearate, calcium stearate and paraffin-based stearic acid lubricant with a total lead content of 40.6% by weight. in a 2.6 wt. parts and 2.80 wt. parts per 100 wt.

Claims (2)

239153 5 parts PVC to be added to the resultant 1.12% by weight. lead. The mixture contains a complex stabilizer in a dosage of 2.6 wt. parts to 1ΌΌ parts by weight of PVC were only processable on some types of twin-screw extruders. The mixture containing 2.80 parts by weight of the complex stabilizer was workable in all types but also in the mixture produced by the 110 ° C 4.3 mm and 0 160 X 6.2 mm pipes did not pass the pressure test at 20 ° C and tangential strain 46 a48 MPa. EXAMPLE 4 A PVC blend was prepared on a fluid mixer containing a complex stabilizer as a stabilizing and lubricating system, a base-biphasic lead-containing stearate, dibasic lead stearate, calcium stearate, and baseparaffin and stearic acid-total stearic acid stabilizers. % wt. and calcium 0.58 wt. in a mass of 1.9 wt. parts per 100 wt. PVC and the complexine stabilizer of the same composition, but with a low content of calcium stearate and a higher content of paraffins and stearic acid having a total content of -40% by weight. at a dose of 0.9 hmo-t. -Weight 100 pcs. PVC parts. From this grain, PVC0 160 X 6.2 mm pressure pipes with a sigma-permissible tangential tension of 12 were made on a two-wedge extruder with a conical thread-like end-pipe. 5 MPa, which, at a tensile stress of 48 MPa, complied with the prescribed pressure test over a period of 1.3-2.0 hours at 20 ° C. Example 5 The Ak-o in Example 4 was made from a PVC-free composite stabilizer mixture on a twin-screw extruder with parallel PVC0 110 x 4.3 mm pipe threads, permissible tangential tension-g-m and 12.5 MPa. which satisfy all of the prescribed pressure tests, including tests at 20 ° C with a tensile strain of 46 MP-α at rupture of 1.5 to 3.2 hours. Example A PVC mixture was prepared on a fluid mixer containing a combination of complex stabilizers as a stabilizing and lubricating system as in Example 4, with a first weight of 2.2 wt. parts and the second 0.6 parts per 100 parts by weight. PVC parts. From the thus prepared mixture, pressure tubes of PVC permissible tensile tension 12.5 MPa -o r-ozmeroch0 225 X 8.7 were made on a twin-screw cone-threaded machine. mm and 0 160 X 6.2 mm, which comply with all prescribed pressure tests, including a pressure test at 20 ° C and a tangential tension of 46 and 48 MPa and time to burst of 2.3 to 8.5 hours. The subject matter of the invention can be utilized in the plastics industry for the production of PVC pressure tubes, in particular tubes of higher permissible tension and, in general, in the mixing of PVC mixtures into non-clogged articles. OBJECT CLAIMS 1. A process for the production of PVC pressure tubes with additional tangential tension of sigma 12.5 MPa using a PVC blend extrusion technology, characterized in that the PVC blend comprises a combination of a complex stabilizer and a tribasic and / or tetrabasic lead sulfate. with the addition of neutral / or dibasic lead-stearate, calcium stearate and lubricants, preferably paraffins and / or stearic acid having a total lead content in the complex stabilizer, preferably 42.0% by weight. and calcium, preferably -0.58 wt. with dosing dosages of 0.2 to 2.8 wt. parts and a complex stabilizer based on tribasic and / or botetrabasic lead sulphate with the addition of a neutral and / or dibasic lead stearate, a small amount of stearate-calcium with a higher content of lubricants, with the advantage of paraffins and / or stearic acid in total lower content of lead in a complex stabilizer, preferably 40.6 wt. 0.2 to 2.8 wt. parts per 100 parts by weight of PVC, wherein the total content of the inventive complex stabilizers in the mixture is 1.8-3.0% by weight. parts per 100 wt. PVC parts. 2. A method for producing PVC pressure tubes with a sigma 12,5 MPa tangential tension according to claim 1, characterized in that the PVC composition comprises a combination of a complex tribasic and / or tetrabasic lead sulfate stabilizer by addition of neutral and / or dibasic lead stearate, calcium stearate and amastive, preferably paraffin-and / or stearic acid, having a total lead content in the complex stabilizer, preferably 42.0 wt. and calcium, preferably 0.58% by weight of the compositions, preferably 1.9-2.2% by weight. parts per 100 wt. parts of PVC and a complex tri-c-alkali and / or tetrabasic lead sulphate stabilizer with the addition of neutral and / or dibasic lead stearate, a small amount of calcium stearate with a higher content of the feed, preferably paraffins and / or or stearic acid having a total lower content of about 239153,78, the total content of both complex stabilizers in the mixture being preferably 2.4 to 2.8 wt. parts per 100 wt. PVC parts. in a complex stabilizer, preferably 40.6 wt. at dosing, preferably 0.8 to 0.9 wt. works per 100 wt. parts PVC, Severografia, n. p., race 7, Most price 2,40 Kcs