JPS6014780B2 - polyolefin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to polyolefin compositions with improved transparency.

In general, polyolefins are widely used as molding materials for films, molded articles, fibers, etc., but depending on their use, they are required to have excellent transparency.

For example, in the case of packaging films, the contents must be clearly visible, as seen in the packaging of foods, textiles, etc., and in the case of molded products, discoloration may occur if transparency is impaired. Even if an agent is added, the image becomes unclear. As a result of various studies aimed at improving these drawbacks of polyolefins, the present inventors discovered that the transparency of polyolefins can be significantly improved by incorporating certain substances, and the present invention has been made based on this finding. Reached.

That is, the gist of the present invention is that polyolefin and
6 and a glyceride having an acyl group having 8 to 22 carbon atoms.

To explain the present invention in detail, in the glyceride blended into the polyolefin, one of the three hydroxyl groups of glycerin is a lower fatty acid having 2 to 6 carbon atoms, and the other one is a lower fatty acid having 8 to 22 carbon atoms.
must be esterified with higher fatty acids,
The other one is a diacetin or triacetin compound (hereinafter referred to as "hybrid glyceride") which remains as a hydroxyl group or is esterified with a lower fatty acid having 2 to 6 carbon atoms or a higher fatty acid having 8 to 22 carbon atoms.

Of course, the acyl groups of the triacetin compounds may all be different. The higher fatty acid may be saturated or unsaturated as long as it is a fatty acid having 8 to 22 carbon atoms, and is preferably a fatty acid having 10 to 18 carbon atoms. Also, lower fatty acids have 2 or more carbon atoms.
6 may be used. in particular,
For example, diacetylmonolaurylglycerin, diacetylmonopalmitylglycerin, diacetylmonooleylglycerin, monoacetyldilaurylglycerin, monoacetylmo/palmitylglycerin, monoacetyldioleylglycerin, monoacetylmonolaurylglycerin, monoacetylmonooleylglycerin, dibropioni monolaurylglycerin, dicaproylmonolaurylglycerin, dicabroylmonopalmitylglycerin,
Examples include monoacetylmo/caprylic glycerin, monoacetylmonogracidylglycerin, monopropylmonogracidylglycerin, and monoacetylmo/hercylglycerin. These hybrid grise IJ de
Of course, two or more types may be used in combination.

Although the lower fatty acid mono-, di-, or triester of glycerin temporarily improves the transparency of the resin composition,
It has poor compatibility with the resin composition and tends to bleed onto the surface, making it difficult to maintain transparency over a long period of time.

Furthermore, higher fatty acid mono-, di-, or triester of glycerin has good compatibility with the resin composition, but cannot sufficiently improve transparency. Any known polyolefin can be used as a component of the composition of the present invention.

Usually olefins having 2 to 8 carbon atoms, especially olefins having 2 to 8 carbon atoms.
A polyolefin obtained by polymerizing Q-olefin is used. Specifically, polyethylene polymerized by high pressure method, polyethylene polymerized by medium pressure method, polypropylene,
Examples include polybutene and polyisobutene. These polyolefins may be copolymers, and examples of copolymers include olefins such as those obtained by copolymerizing ethylene with propylene, butene, isobutene, styrene, acrylic acid, acrylic ester, or vinyl acetate. be able to.

In the case of copolymers, it is preferred that the copolymer monomer accounts for less than 2% by weight of the main polymer monomer (olefin). A copolymer containing 20% or less of copolymer monomers can be easily formed into a film. Among polyolefins, the greatest effect is observed when polyethylene or a copolymer containing ethylene as a main component is used.

The effect is particularly great when using low-density polyethylene or ethylene-vinyl acetate copolymer with a density of 0.94% or less polymerized by a high-pressure method. The amount of hybrid glyceride in the composition of the present invention may be any amount, but is usually 0.4 to 20% by weight, preferably 0.5% by weight based on the polyolefin.
Contain up to 15% by weight.

If the amount of mixed glyceride is less than the above range, it is difficult to expect a substantial effect, and even if it is used in a larger amount than the above range, no significant improvement in transparency can be expected, which is also economically disadvantageous. Not only this, but also problems such as stickiness of the film are likely to occur. The composition of the present invention may be prepared by any conventional method of adding additives to polyolefins.

Specifically, examples include a mechanical blending method, a mixing method using an extruder, a hot roll, a Banbury mixer, etc. The mixed material can be used as is or in the form of pellets. Of course, the composition of the present invention can have the mixed glyceride added at any stage before the polymerization of the polyolefin, provided it does not react, up to the shaping of the final product. Furthermore, the composition of the present invention includes a wear resistance improver,
Stabilizers, tackifiers, colorants such as dyes and pigments, plasticizers, reinforcing agents, surfactants, antistatic agents, inorganic fillers, thickeners, nucleating agents, flame retardants, molding agents or emulsifiers. Additives such as protective agents may be added together, and polymers such as polytetrafluoroethylene, polyester, and ABS resin may also be added. Molding of the composition of the present invention can be carried out by various well-known methods.

For example, by employing extrusion molding, it can be made into a film sheet. In particular, the composition of the present invention provides suitable results when a film is produced by an inflation molding method. Of course, it is also possible to produce a T-die film using the composition of the present invention. Films, molded articles, and fibers obtained from the composition of the present invention have extremely good transparency and resin surface gloss, and the mechanical strength of the polyolefin itself is hardly impaired.

A film produced from the composition of the present invention can be suitably used as an industrial stretch film or a household wrap film. The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited in any way by the Examples unless the gist of the invention is exceeded.

Examples 1 to 10 and Comparative Examples 1 to 2 Low density polyethylene (registered trademark Novatec-LF251
, melt index: 2.0, density: 0.918) diacetylmonolaurylglycerin, diacetylmonooleylglycerin, monoacetylmonolaurylglycerin, monoacetyldilaurylglycerin, and monooleylglycerin are shown in Table 1. Blend to the desired amount,
Mix and pellet using a Banbury mixer at 14,000.

Transparency evaluation sample: screw diameter 40 side, L no D = 2
2. A film was formed using a blown film manufacturing apparatus with a die diameter of 10 mm under the following conditions. That is, molding temperature 160oo, extrusion rate 9k9/hr, blow-up ratio 15
A film of 0.05 willow thickness was obtained. Also, transparency is
It is indicated by the degree of cloudiness (ASTMDIO03-52r). The results are shown in Table 1 along with comparative examples.

As seen in Table 1, the composition according to the invention exhibited excellent transparency. Table 1 Additive A Diacetylmonolaurylglycerin Additive B
Diacetyl monooleylglycerin additive C Mo/acetylmonolaurylglycerin additive D Monoacetyldilaurylglycerin additive E Monooleylglycerin Examples 11-12 and Comparative Examples 3-4 In Example 1, low density Registered polyethylene trademarks: Novatec-LF250 (melt index: 2, density: 0.918) and F150 (melt index: 2)
, density: 0.925), and the transparency was evaluated.

The results are shown in Table 2. Table 2 Examples 13 to 14 and Comparative Example 5 High-density polyethylene (registered trademark: / Batek EROI0
, melt index: 1.0, density: 0.955) and diacetyl monolauryl glycerin were blended in the amounts shown in Table 3, and mixed pellets were prepared using a Banbury mixer.

Claims (1)

[Claims] 1 Polyolefin and carbon number 2-6 and carbon number 8-22
A polyolefin composition comprising a glyceride having an acyl group.