DD211801A1 - METHOD FOR MODIFYING THE SURFACE PROPERTIES OF OLEFIN COPOLYMERS - Google Patents

Abstract

A process for modifying the surface properties of semi-finished products and moldings from olefin copolymers to improve the bondability, printability, metallizability and paintability was to be developed. According to the process of the invention, semi-finished products and molding materials based on norbornene-ethylene copolymers are treated with ionizing radiation.

Description

VSB Leuna-Werke Leuna,

^rl Walter Ulbricht "

LP 8285

Title of the invention

Process for modifying the surface properties of Qlefink polymers

Field of application of the invention

The invention relates to a method for surface modification of semi-finished products and molded materials from Qlefinkopolymeren · By modifying the surface of the semifinished product or, the molding material in particular an improvement in the bondability, printability, metallizability and the adhesion of paint layers is achieved.

Characteristic of the known technical solutions

It is known that iTorbornen-Bthylen copolymers are brittle-hard thermoplastics (US-PS 2,799,668, GB-PS 777 414, DD-PS 103 224) * For modification is known (DD-PS 129 799), dai3 the addition of Elastomers improve the impact strength and the impact resistance of the polymer

combination with respect to the pure Horbornen-Ethyien copolymer causes. It has already been proposed to improve the heat resistance, dimensional stability, hardness and rigidity of the horbornene-y-ethylene copolymers by adding reinforcing materials (WP C08L 235 394/1). Combinations of boron-ethylene copolymers and polyamides have an increased solvent resistance compared to the pure copolymer (WP G08L 235 392/5). According to DD-PS 131 190 a process for the galvanization of horbornene-ethylene copolymers is known *

Specific areas of application require improved adhesiveness, printability, metallizability and adhesion of lacquer coatings in semifinished products and molded materials based on 01efin ~ Kopj.ymeren »

Object of the invention

The aim of the invention is to achieve a permanent bondability, printability and adhesion of paint coatings by modifying the surface of semi-finished products and molding materials based on olefin copolymers. «

Explanation of the essence of the invention

The object of the invention is to improve the bondability, printability and adhesion of lacquer layers in semifinished products and molded materials based on continuous copolymers by a suitable modification process. This object is achieved by a process for modifying the surface properties of olefin copolymers as semifinished products and mold materials. in particular to improve the bondability, printability, metallizability and paintability solved. wherein according to the invention, the modification of the surface properties of semifinished products and mold materials based on horbornene-ethylene copolymers and Ziombinationen Korbornen-Bthylen-copolymers with elastomers, thermoplastics, fillers,

Reinforcing agents and plastic additives by treatment with ionizing radiation takes place. Advantageously, the treatment with ionizing radiation takes place at a surface tempera door of 340 to 410 K. As ionizing radiation with advantage plasma electrical discharges such as corona * discharges, Hiederdruckhochfrequenzentiadungen and Hiederdruckgleichspannungsentladungen used. In the case of plasma-electric discharges, the discharge gas used is advantageously oxygen, nitrogen, ammonia, noble gas or mixtures of these gases. As ionizing radiation and electromagnetic radiation such as UV, X-ray, gamma or laser radiation can be used. Also corpuscular radiation such as beta or alpha radiation is used with advantage. The surface modification of norbornene-ethylene copolymers by ionizing radiation leads to the formation of polar groups on the plastic surface, via which a chemical or, electrostatic adhesion of the material can take place. Thus, electron bombardment of the 0.15 MGy dose copolymer causes a shift in the intensity ratio 00 band / OH band ^E i72c / ^E i460 from 0.033 to 0.147. If plasma-electric discharges are used as ionizing radiation, additional morphological changes take place due to erosion and re-occlusion processes. In particular, high modifying effects at short exposure times to the ionizing radiation are achieved if the radiation action takes place at elevated temperature below the range of the sorbornene-ethylene copolymer. The increased surface temperature of the inorganic or semi-finished product can be achieved by thermal treatment before or during treatment with ionizing radiation.

The norbornene ethylene copolyners contain from 25 to 95 % iol%, preferably from 40 to 80% by mol, of XTcrbornene. For the treatment with ionizing radiation, semi-finished products such as plates, foils and PiOfile as well as laminating materials can be used, which can be produced by injection molding, transfer molding or other processes

-A-

were manufactured.

Exemplary embodiments Example 1

Sin with 0.2 % 4 ₅ 4-thio bis (3-metfayl-6-tert-butylphenoi) stabilized IJorbornene ethylene copolymer having a Yicat temperature of 402 K is sprayed to test specimens at a melt temperature of 530 K. ,

The specimens are subjected to a high-frequency low-pressure discharge (duration 2 min *) in oxygen at a pressure of 40 Pa and a frequency of 2 MHz. «

After bonding with epoxy resin have the test specimens

2 2

a tensile shear strength of 2.5 U / ram, versus 0.5 H / mm

in the untreated material

 Example 2

Horbornene ethylene copolymer test specimens according to Example 1 "are subjected to corona discharge at room temperature in air for 25 s and bonded with epoxy resin. The release strength of the bonded specimens is 12.5 N / mm, compared to 4j5 N / mm for the untreated material. The corona treatment reduces the contact angle (water) from 85 to 30 °.

Example 3

Test specimens of norbornene-ethylene copolyester according to example 1 are corona discharge-coated for 1 s at a surface temperature of 3ö5 K in air and bonded with epoxy resin. «

The bond strength of the bond is 13 Η / mm.

Example 4

A polymer combination of 78 parts of a Horbornen-Bthyien copolymer with a horbornene content of 50 MoIiS and 22

Parts of an ethylene - / inyl acetate copolymer having a vinyl acetate content of 32 pigs and a melt index of 0.5 g / 10 min at 463 K are sprayed at 56 ° K into a half shell for a switch housing. After passage of the housing through an irradiation station with a 0.2 MeV electron accelerator, permanent printing is achieved.

Claims (6)

invention claim 1. A process for modifying the surface properties of olefin copolymers as semifinished products and molding materials, in particular , in particular to improve the bondability, printability, metallizability and paintability, characterized in that the modification of the surface properties of semi-finished products and fillers based on Itforbornen-ethylene copolymers and combinations of norbornene-ethylene copolymers with elastomers, thermoplastics, fillers. Reinforcing agents and plasticizers by treatment with ionizing radiation takes place. 2. The method according to item 1, characterized in that the treatment is carried out with ionizing radiation at a surface temperature of 340 to 410 K. 3 «method according to item 1, characterized in that are used as ionizing radiation plasma electrical discharges such as corona discharges, low-pressure high-frequency discharges or Niederdruckgkeichsspannungsentladungen» 4 Method according to item 1, characterized in that oxygen, nitrogen, ammonia, inert gas, or mixtures of these gases are used as the discharge gas in the case of plasma electrical discharges. 5. The method according to item 1, characterized in that electromagnetic radiation such as UV, X-ray, gamma or laser radiation is used as ionizing radiation. 6. The method according to item 1, characterized in that as ionizing radiation corpuscular radiation such as beta or alpha radiation is used.