JPH0621198B2 - Method for imparting antistatic property and antifogging property to polyolefin resin - Google Patents

Description

The present invention relates to a method for imparting antistatic property and antifogging property to a polyolefin resin.

In general, synthetic polymer materials have strong hydrophobicity, and as a result, due to electrostatic properties, etc., troubles and static problems in various processes occur during the manufacturing process of molded articles using the materials and the stage of using the molded articles. Electric shock, dust adhesion, water droplet aggregation, etc.
It is prone to many problems. The same applies to the polyolefin resin, for example, when the film or sheet that is a molded product is used for packaging or agriculture, the problems due to the electrostatic properties described above and minute water droplets on the surface of the molded product in a humid atmosphere are described. Is a major obstacle.

Therefore, it is required to impart antistatic property and antifogging property to the polyolefin resin, and as the industrially most advantageous means for meeting the demand, a hydrophilic compound such as an antistatic agent is added to and mixed with the polyolefin resin. There is a way to do it.

The present invention relates to such a method, by mixing a specific combination of additives to a polyolefin resin, without impairing other physical properties such as the original appearance of the polyolefin resin, the polyolefin resin is excellent in stability over time and antistatic. And a method for imparting antifogging property.

<Prior Art and Problems Thereof> There have been many proposals as below as a method for imparting antistatic property and antifogging property to a polyolefin resin by adding various additives. For example, a method of using N, N-bishydroxyethylalkylamine as a main agent and a polymer in combination (Japanese Patent Publication No. 48-17746), and a method of using a polyhydric alcohol fatty acid ester in the main agent (Japanese Patent Publication No. 44-9).
25), a method in which an aliphatic alcohol is used as a main agent (Japanese Patent Publication No. 46-1253), and a method in which a glycerin monofatty acid ester and an organic phosphite are used in combination as a main agent (JP-A-58).
No. 79042), a method using N, N-bishydroxyethylalkylamine fatty acid ester as the main agent (JP-B-5512060), a method using alkanolamide as the main agent (JP-A-56-2333), N, N- A method using a bishydroxyethylalkylamine fatty acid ester (JP-A-58-191729) or a method using a glycerin mono-fatty acid ester in combination (JP-A-54-4).
8866), a method using a betaine-type amphoteric surfactant (JP-B-49-5746), and a method using a fatty acid diethanolamide having a carbon number of more than 18 (JP-A-54-1).
4452), a method in which a fatty acid diethanolamide and a sorbitan fatty acid ester are used in combination (JP-A-53-6924).
7) etc.

However, N, N often found in these conventional proposals
-According to the method of using bishydroxyethylamine or its esterified derivative, since they have a strong property of bleeding to the surface of a molded article with time, when an amount that gives a desired effect in the initial stage is used, after aging Excessive bleeding tends to cause problems such as surface stains and blocking in a molded product such as a film or sheet, and conversely, when an amount that gives a preferable effect after aging is used, a desired effect can be initially obtained. Even if other components are used together, it is difficult to obtain a stable effect over time in practical use. Further, according to the method of using the betaine-type amphoteric surfactant, since it has a weak property of migrating to the surface of the molded article, it is generally difficult to adopt because it requires some step such as heating or corona treatment after addition. The method using the aliphatic alkanolamides is almost the same. Furthermore, even by other conventional proposals in which various components are used together in order to supplement anti-blocking properties, slip properties, etc., the desired effect cannot be actually obtained, or deterioration of the effect over time is promoted, In reality, there are many problems such as whitening of the surface of the molded product.

<Problems to be Solved by the Invention> The present invention is based on the premise that the polyolefin resin is provided with sufficient antistatic property and antifogging property. And that the antifogging property deteriorates over time, such as instability, whitening, coloring, surface stickiness, and other physical properties such as appearance and other physical properties, and complicated processes such as heating and corona treatment. It is necessary to solve the above problems.

<Means for Solving Problems> However, as a result of intensive studies to solve the above-mentioned problems, the present inventors have found that in a predetermined mixture of glycerin-mixed fatty acid ester and diethanolamide, the weight ratio of both and It was found that when an additive having a specified carbon number distribution state in the mixture was applied, an unpredictable initial effect could be obtained from both simple substances, and the present invention was completed.

That is, the present invention comprises the following glycerol mixed fatty acid ester corresponding to A and diethanolamide corresponding to B, and the weight ratio of both is 5/5 ≦ A / B ≦ 8/2, both of which are An additive satisfying the condition (a) is added in an amount of 0.05 to 2.0% by weight with respect to the polyolefin resin. Pertain.

A: The difference in carbon number among the fatty acids having 12 to 22 carbon atoms is 4
A glycerin-mixed fatty acid ester having a monoester content of 90% by weight or more, which is derived using two or three fatty acids within

B: Diethanolamide derived using a fatty acid having 12 to 22 carbon atoms.

(a) The total amount of each component corresponding to A and each component corresponding to B which are within the same carbon number range where the difference in carbon number of the fatty acid used is within 4 is 80% by weight of the total amount of A and B. Above, and in the total amount of each of the above components, the weight ratio of both components is 5/5 ≦ A, the total amount of each component that corresponds to A / the total amount of each component that corresponds to B ≦ 8/2.

Specific examples of the glycerin mixed fatty acid ester of A used in the present invention include glycerin monoester of mixed fatty acid of lauric acid and myristic acid, glycerin monoester of mixed fatty acid of myristic acid, palmitic acid and stearic acid, palmitic acid and Examples thereof include glycerin monoester of mixed fatty acid of stearic acid, glycerin monoester of mixed fatty acid of stearic acid, arachidic acid and behenic acid. Usually, glycerin fatty acid ester is obtained as a mixture of mono, di and triesters by esterification or transesterification reaction. In this case, therefore, in the present invention, the mixture is purified so that the content of monoester is 90% by weight or more. You need to use the one that you made. If the purity is lower than this, the target performance of the present invention cannot be obtained. In addition, since a normal fatty acid uses natural fats and oils as a raw material source and is obtained in a mixed fatty acid state having a carbon number distribution, in the present invention, in consideration of the actual conditions of the raw material source, a mixed fatty acid having a predetermined carbon number distribution is used. Glycerin mixed fatty acid esters derived from fatty acids are used. When a glycerin fatty acid ester derived from a single fatty acid having a monoester content of 90% by weight or more is used, sophisticated purification means such as fractional distillation is required. It is much more economical because it does not require any refining means.

On the other hand, specific examples of the diethanolamide of B used in the present invention include lauric acid diethanolamide, myristic acid diethanolamide, palmitic acid diethanolamide, stearic acid diethanolamide, and behenic acid diethanolamide. These are usually
It is obtained from equimolar amounts of diethanolamine and a fatty acid or a fatty acid ester by amidation or aminolysis.

In the present invention, the weight ratio when using A and B is 5
It is necessary that / 5 ≦ A / B ≦ 8/2. Outside this weight ratio range, the favorable interaction between A and B is lost.

Further, in the present invention, the distribution of the carbon number of the acyl group (the carbon number of the fatty acid used when inducing A or B) in the mixture of A and B as described above is made to exert a preferable interaction between them. Is important for. It is necessary that all of the carbon numbers are in the range of 12 to 22, and within this range, the closer the two carbon numbers are, the better the effect is exhibited. It is necessary to satisfy the above condition (a). If the carbon number of the acyl group is out of the range of 12 to 22 or the condition (a) described above regarding the distribution state of the carbon number is not satisfied, the intended effect of the present invention cannot be obtained.

Regarding the distribution of the carbon number of the acyl group in the mixture of A and B, in the same meaning as above, when the above condition (a) is satisfied and at the same time the following condition (b) is satisfied, The effects of the present invention are most excellent.

(b) There are one or more pairs of a component corresponding to A and a component corresponding to B in which the fatty acids used have the same number of carbon atoms, and the weight ratio of both is 5/5 in each pair. ≦ A / component corresponding to B ≦ 8/2, and the total amount of both components forming the pair is 70% by weight or more of the total amount of A and B.

It is necessary to use the above-described additive consisting of A and B in an amount of 0.05 to 2.0% by weight based on the polyolefin resin. If the amount is too large or, conversely, too small, the intended effect of the present invention cannot be obtained.

<Operation etc.> The method of using the additive in the present invention is not particularly limited. With respect to the polyolefin resin, the condition (a) is satisfied, preferably the conditions (a) and (b) are simultaneously satisfied, and A and B may be added separately, or both of them may be previously added. It may be added after mixing, or may be added directly to the resin, or may be added once after forming a high-concentration master batch.

The resins to which the present invention can be applied are all polyolefin resins, and include polyethylene, polypropylene, polybutadiene, and resins obtained by copolymerizing these with other monomers such as vinyl acetate, ethyl acrylate and acrylic acid. And the effect of the present invention is a molding processing method such as inflation, casting, extrusion molding, injection molding, a film,
It is not restricted by the form of molded products such as sheets and fibers.

In addition, a lubricant, a stabilizer, an anti-blocking agent, etc. may be used together for the purpose of carrying out the present invention for other purposes as long as the effects of the present invention are not impaired.

<Effects of the Invention> As described above, the present invention does not require any troublesome extra steps such as heating and corona treatment, and does not adversely affect the appearance and other physical properties of the polyolefin resin, and thus the polyolefin resin can be aged over time. Is stable and has an effect of imparting sufficient antistatic property and antifogging property.

<Examples> Hereinafter, the configurations and effects of the present invention will be more specifically described with reference to Examples and Comparative Examples, but the present invention is not limited to the Examples.

-Examples 1-4, Comparative Examples 1-9 Low-density polyethylene resin (Sumitomo Chemical Co., Sumikasen F
-208-1), add each of the additives listed in Table 1 to 4
After kneading at a temperature of 150 ° C. by using a roll kneading group so that the content of the mixture was 0.8% by weight or 0.8% by weight (Comparative Example 5), a 3 mm square pellet-shaped master batch was produced with a sheet cutter.

Then, after mixing 5 parts by weight of each masterbatch with 95 parts by weight of the low-density polyethylene resin, a cylinder temperature of 18
Inflation molding was performed under the conditions of 0 to 210 ° C. and a blow-up ratio of 2.0 to produce a film having a thickness of 30 μ, which was used as a sample.

Examples 5 to 7 and Comparative Examples 10 to 12 Instead of the low density polyethylene resin, a linear low density polyethylene resin (Mitsui Petrochemical Co., Ltd., Ultzex 3021) is used.
F), instead of each additive shown in Table 1, each additive shown in Table 2 was used, and each additive concentration of the master batch was set to 8% by weight. Same as the case.

-Examples 8-11 and comparative examples 13-19 Polypropylene resin (Sumitomo Chemical Co., Ltd., Noblen F-6
411), using a Labo Plastomill (manufactured by Toyo Seiki Co., Ltd.) at a temperature of 200 ° C. so that each additive shown in Table 3 becomes 0.6% by weight or 2.2% by weight (Comparative Example 13).
After kneading for 5 minutes, the sheet was pressed at a temperature of 200 ° C. and a pressure of 350 kg / cm ² for 1 minute to prepare a sheet having a thickness of about 100 μ, which was used as a sample.

Then, using each of the above samples, measurement or evaluation was performed as follows. The results are shown in Tables 4 to 6.

・ Surface condition (appearance) Leave each sample in a constant temperature and humidity room at 20 ° C x 60% RH for 3
After two days and two months, the degree of whitening of the surface was visually evaluated according to the following criteria.

⊚: No whitening ○: Partially whitening △: Whole whitening ×: Fully whitening ・ Antistatic property Each sample was kept at 20 ° C x 60% RH Leave it in the humidity chamber for 3
After two days and two months, the surface resistance was measured under the same conditions as the standing conditions.

・ Anti-fogging property 30 ml of water at 20 ° C was placed in a beaker with a capacity of 100 ml, and this was left in a constant temperature and humidity chamber at 20 ° C x 60% RH for 3 days or 2 months. After standing for 1 hour, the state of water droplets attached to the inner surface of each sample was visually evaluated according to the following criteria.

5: Transparent with almost no water droplets attached.

4: Large water droplets are slightly attached, but they are transparent.

3: Adhesion of water droplets is partially observed, but there is a transparent feeling.

2: Many water droplets are attached and transparency is lowered.

1: Microscopic water droplets adhere to the entire surface, resulting in poor transparency.

The effects of the present invention are also apparent from the results of each example with respect to each comparative example in Tables 4 to 6.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display area C08K 5:20)

Claims (2)

[Claims] 1. A glycerin mixed fatty acid ester corresponding to the following A and a diethanolamide corresponding to the following B,
The weight ratio of both is 5/5 ≦ A / B ≦ 8/2, and the amount of the additive that satisfies the following condition (a) is 0.05 to 2.0% by weight based on the polyolefin resin. A method for imparting antistatic property and antifogging property to a polyolefin resin, characterized in that A: The difference in carbon number among the fatty acids having 12 to 22 carbon atoms is 4
A glycerin-mixed fatty acid ester having a monoester content of 90% by weight or more, which is derived using two or three fatty acids within B: Diethanolamide derived using a fatty acid having 12 to 22 carbon atoms. (a) The total amount of each component corresponding to A and each component corresponding to B which are within the same carbon number range where the difference in carbon number of the fatty acid used is within 4 is 80% by weight of the total amount of A and B. Above, and in the total amount of each of the above components, the weight ratio of both components is 5/5 ≦ A, the total amount of each component that corresponds to A / the total amount of each component that corresponds to B ≦ 8/2. 2. In the description of claim 1, A
A method for imparting antistatic property and antifogging property to a polyolefin resin, wherein the glycerin mixed fatty acid ester corresponding to the above and the diethanolamide corresponding to B further satisfy the following condition (b). (b) There are one or more pairs of a component corresponding to A and a component corresponding to B in which the fatty acids used have the same number of carbon atoms, and the weight ratio of both is 5/5 in each pair. ≦ A / component corresponding to B ≦ 8/2, and the total amount of both components forming the pair is 70% by weight or more of the total amount of A and B.