DE2331774A1 - POLYOLEFINE MOLDING COMPOUNDS THAT DEGRAD ACCELERATELY UNDER LIGHTING - Google Patents

Description

Badisehe Anilin- & So <la-Fabrik AG ο q q ι 7 7 /

Our reference: 0.Z.29 9 ^ 7 HWz / sb 67ΟΟ Ludwigshafen, June 20th, 1973

Polyolefin molding compounds that degrade more rapidly when exposed to light

The present invention relates to polyolefin molding compositions which degrade more rapidly under the action of light, containing (I) a thermoplastic, synthetic, high-polymer polyolefin and (2) 0.01 to 3 percent by weight - based on the polyolefin one the degradation of the polyolefin under the action of light accelerating substance (sensitizer).

Molding compositions of this type are known; As polyolefins, they generally contain polymers of ethylene or propylene, ie Bulk plastics from which large quantities of disposable products are made, e.g. packaging in foil or other Shape. In addition to the polyolefins, the molding compounds of the type in question also contain sensitizers, i.e. substances that promote degradation accelerate the polyolefin under the action of light. As such substances, e.g. descendants of the Jjp-Pyrons have been used (French Patent Specification 2,060,667).

The actual task of the sensitizers is to remove the molding compound to make manufactured products environmentally friendly in the sense that they rot as quickly as possible after use. Besides the sensitizers usually have to meet other conditions. It is required, for example, that they have the other properties the molding compounds do not, or as little as possible, adversely affect, for example the processability and the physical and chemical behavior values. In many cases, the sensitizers must also be physiologically harmless (food packaging I).

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409884/1208

. 2 - O.Z. 29 9 ^ 7

The task of the present invention was for the initially defined polyolefin molding compounds a sensitizer to show which is superior to the known.

It has been found that this object can be achieved if the sensitizer used is bis- (cyclopentadienyl iron diearbonyl) begins.

The present invention accordingly relates to polyolefin molding compositions, which degrade more rapidly under the action of light, containing (l) a thermoplastic, synthetic, high polymer polyolefin and (2) 0.01 to j5, preferably 0.0p up to 0.5 percent by weight - based on the polyolefin - of one which accelerates the degradation of the polyolefin under the action of light Substance (sensitizer), the molding compositions according to the invention are characterized in that they are used as a sensitizer Bls- (cyclopentadienyl iron dicarbonyl) contain.

In other words, the present invention relates to the use of bis (cyclopentadienyl iron dicarbonyl) as a sensitizer in polyolefin molding compounds that accelerate when exposed to light degrade and contain (l) a thermoplastic, synthetic, high-polymer polyolefin and (2) 0.01 to 3 * preferably 0.05 to 0.3 percent by weight - based on the polyolefin - a substance that accelerates the degradation of the polyolefin when exposed to light (sensitizer).

Polyolefins suitable for the purpose of the invention are relevant usual. Polyethylene, polypropylene and also polybutene- (1) have proven to be particularly suitable. - The for According to the invention, suitable polyolefins are in large Variety is commercially available, so that there is no need for more detailed information on them, it should only be mentioned that the polyolefins the may contain relevant customary auxiliaries or additives, e.g. propellants for the manufacture of shaved products, lubricants, Pigments, dyes, etc. "If the polyolefins also contain light stabilizers, these generally act as sensitizers to a certain extent: against,

Λ. 409884/1208

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The sensitizer to be used according to the invention is bis (cyclopentadienyl iron dicarbonyl). This substance as such is known (cf. e.g. "Inorganic Syntheses", Volume VII, page 110 ff, McGraw-Hill Book Company, Inc .; 1963), so that more detailed explanations can be found to spare him.

The production of the polyolefin molding compounds in question the components can be done in a simple manner, as is usually the case with additives in the affected polyolefins - if possible homogeneous - incorporated, e.g. by rolling or extruding.

The processing of the molding compositions into molded parts can also be carried out without further ado take place with the usual devices for the polyolefins concerned.

The molding compounds will be used primarily for the manufacture of products that are supposed to degrade quickly when exposed to light. this are primarily products intended for packaging purposes, such as containers and foils made from foamed or non-foamed molding compounds: - but also other products, e.g. mulch foils for horticultural and agricultural purposes come into consideration.

example 1

100 parts by weight of a commercially available polyethylene: contains (O density, 9l8 g / cnr) that no photoactive additives, is homogeneously mixed with 0.3 parts by weight of bis-iCyclopentadienyleisendicarbonyl) mixed (Welding extruder; 240 ⁰ C).

From this and an identical but unsensitized molding compound, 60 / U thick films were blown. On them the light-induced Degradation followed by the tensile test. The following tensile strength values at break were measured:

Reporting days with Hg-Nieder-

pressure fluorescent lamps

0 9 14 21

Sens. Slide c ^ n «: or> ^ <t _O r«! not

(Elongation at break) ^{55O% 205% 2} ^ measurable

.Foil

(Elongation at break)

Λ 409884/1208

- 4 - 0.2. 29

100 parts by weight of a commercially available polypropylene containing no additives is photoactive, homogeneously mixed with 0.1 parts by weight of bis (Cyclopentadienyleisendicarbonyl) mixed (Buss-Ko-kneader: 210 ⁰ C).

60 / U thick films from this molding compound build up when exposed to light under comparable conditions significantly faster than equally thick films made of the same, but unsensitized molding compound. The following decrease in elongation at break was observed:

0 6 days exposure time (Hg lamp)

$ 795 $ 370 $ 10 elongation at break

Example 3

100 parts by weight of a commercially available polyethylene (density: 0 * 950 g / cnr) containing the no photoactive additives, is homogeneously mixed with 0.4 parts of bis (Cyclopentadienyleisencarbonyl) mixed (Welding extruder: 24O ⁰ C).

200 / U thick films from this molding compound build when exposed to light under comparable conditions about 4 times as fast as films of the same thickness made from the same but unsensitized film Molding compound.

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Claims (2)

- 5 - O.Z. 29 Claims Z 0 JI / / ΑΙ. Polyolefin molding compounds that degrade more rapidly under the action of light, containing (l) a thermoplastic, synthetic, high-polymer polyolefin and (2) 0.01 to 3 percent by weight based on the polyolefin - a substance that accelerates the degradation of the polyolefin under the action of light (sensitizer), thereby characterized in that the molding compositions contain bis (cyclopentadienyl iron dicarbonyl) as a sensitizer. 2. Use of bis (cyclopentadienyl iron dicarbonyl) as a sensitizer in polyolefin molding compounds that accelerate when exposed to light degrade and contain (l) a thermoplastic, synthetic, high-polymer polyolefin and (2) 0.01 to 3 percent by weight - based on the polyolefin - a substance that accelerates the degradation of the polyolefin when exposed to light (Sensitizer). Badische Anilin- & Soda-Fabrik AG 409884/1208