SU797894A1 - Method of treating second-hand polyethylene - Google Patents

Description

the use of polyethylene, including grinding, washing, drying and granulation, the material is combined with granulation before granulation. compounds of proton-avonor type, taking 0, 5% by weight of the pumpkin and granulation is carried out at a ratio of extrudate flow rates to speed, melt flow rate 2-3, and bis-phenol-2 is used as iroton donor type compounds , 2-methyl-bis-methyl-6-tert-butylphenol) or M-phenyl-P-naphthnpamine.

The amount of proton-ionic compound is determined by the quality of the raw material of EBEC) by the magnitude of the yield.

at break (E). With E over ZOO%, 0.1-0.25% of the chemical compound of the proton-aonor type is introduced into PEB, with E up to 300%, 0.25-0.5% is introduced.

The regeneration process of PEBU is carried out directly in the extruder-granulator at 16O-20O C. In the process of homogenization of PEBU in an extruder-granulator, the cross-links in the PEBU macromolecules are destroyed with the formation of reactive radicals that in turn react with the proton-donor chemical compound and form stable macromolecules with reduced molecular mass.

The extrudate from the granulator is taken into a bath with cooling water (35-40 C).

With respect to the rate of extrusion reception and the rate of melt flow during granulation up to к 0bno podg ryvat more than 2-3. Increasing this ratio above three causes the extrudate to break. Then the extrudate is crushed and dried using conventional techniques.

The obtained granulate can be processed both independently and in a mixture with high-grade PE in various proportions by traditional methods used for polyolefin processing, extrusion, casting, pressing, etc.

Example. A worn polyethylene film for agricultural purposes that meets the requirements of OST 637R6-72 () is fed to a wet grinder for grinding and removing from mechanical impurities. The resulting clear film chips are squeezed in a vineyard type vineyard to a moisture content of 10%, and then dried in a dryer (CK-10O) at an air temperature of 70-8 ° C to a moisture content of 0.1%. Dried crumbs of PEBU are loaded into a pie-type smsitel on a barrel, where it is pre-mixed (powdered) with bis-phenol-2,2-methylene bis (4-methyl-6-tert-butylphenop) in an amount of 0.25 wt.% Regenerate within 15-20 minutes In order to evenly distribute bis-phenol-2,2-methylene bis (4-methyl-6-tert-butylphenol) on the crumb surface, transformer oil in an amount of 3 wt.% Of regenerate is simultaneously fed to the mixer. Powdered chips are sent to the extruder granulator torch.

The temperature in the first zone of the extruder cylinder is 100-12 ° C, in the second zone 120-130 ° C, and the temperature in the third

130-140 ° C, B

the zone of the extruder head of the fourth 140-150 0 and in the fifth 150160 С.

The extrudate is taken into a bath with a temperature of water of 35-40 C. The ratio of the extrudate intake rate to the melt flow rate during granulation is equal to three. After granulation, the extrudate is dried in a dryer at 70-80 ° C to a moisture content of 0.1%.

From this granulate, a film is produced by blown extrusion, the properties of which are presented in the table.

Example 2. A worn polyethylene film for agricultural purposes, meeting the requirements of OST 63786-72 (E-100%), is treated as in Example 1.

Pre-mix (powder) with bis-phenol-2,2-methylene bis (4-methyl-6-tertbutylphenol) in an amount of 0.5 wt.%. Regenerate for 1520 minutes Next material. Processed by the technology described in example 1.

From this granulate, a film is produced by blown extrusion, the properties of which are presented in the table.

EXAMPLE 3 A worn polyethylene film for agricultural purposes, meeting the requirements of OST 63786-72 (), is treated as in Example 1.

Pre-mix (powder) with N.-Phenyl-p-naphthylamine (neozon D) in an amount of 0.25 wt.% Regenerate for 15-20 minutes. Next, the material is processed according to the technology described in example 1.

A film is obtained from this granulate by blown extrusion. whose properties are presented in the table. The use of the proposed method for the processing of PEBU is affordable and economically feasible, it allows recycling 79789 5 4 PEBU by various traditional methods (extrusion, casting, pressing, blowing, etc.) in products with properties that satisfy the conditions of operation.

Stress at break, who / cm

Relative lengthening at break,%

Yield strength at stretching, kgf / cm

Claims (2)

Melt flow index, T, P 10 kg, g / 10 min. Claim 1. Technique for processing used polyethylene, including grinding, washing, drying on a grain; a feature characterized in that, b to restore the rheological properties of polyethylene, dried Before granulation, the material is combined with proton-donor type compounds, taken in an amount of 0.1–0.5 wt.%, and-granulation is carried out at a speedy ratio. extrudate flow to melt flow rate 2-3. 2. The method according to claim 1, is distinguished by the fact that in quality 10098110 GOST 11262-68 450 400450 GOST 11262-68 787075 GOST 11262-68 1,41,51,6 GOST 11645-73 of the Research Institute of Proton-Donor Type use bis-phenol-.2,2-methyl-bis (4-methyl-6-tert-butylphenol) or Y-phenyl-p-naphthylman. Sources of information taken into account in the examination 1. Germany patent No. 2699864, cl. B 29 C 29 / OO, 1977. 2. Men S.M. et al. Recycling of polyethylene film into consumer goods. Sat Ways of quality and production efficiency in local industry, Kiev, Uko.KII local industry, 1977, p. 84-95 (prototype).