JPS6119644A - Linear, low-density polyethylene resin composition - Google Patents

Abstract

PURPOSE:The titled resin composition which has excellent slip characteristics, blocking resistance, etc., does not cause wrinkle in fabrication, and is made by incorporating a specified aliphatic acid amide and/or a specified silica gel into a linear, low-density polyethylene resin. CONSTITUTION:An aliphatic acid amide having a melting point of 60-120 deg.C (e.g. erucamide, oleamide or behenamide) and/or a silica gel having an average particle diameter of 1-20mum and a pore volume of 2ml/g or less in an amount of 0.1-1.5pts.wt. is incorporated into 100pts.wt. linear, low-density polyethylene (having a density of about 0.91-0.96g/cm<3>, containing about 1-60 short-chain aliphatic group branches per 1,000 carbon atoms on its chain).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a linear low-density polyethylene resin composition, and more particularly to a linear low-density polyethylene resin composition with improved slippage, blocking properties, and wrinkle prevention effect during secondary processing.

Linear low density polyethylene has excellent mechanical properties.

Due to its transparency and heat-sealability, it is expected to be used as packaging materials and agricultural films.

However, when linear low-density polyethylene is used as a film, it has poor slippage and insufficient blocking properties, making it difficult to apply it to the above-mentioned uses.

Therefore, the present inventors conducted extensive studies to improve the slippage, blocking properties, etc. of linear low-density polyethylene without impairing its inherent good mechanical properties, transparency, and heat sealability. We have discovered that a linear low-density polyethylene resin composition with improved physical properties can be obtained by blending a predetermined amount of a fatty acid amide and/or a predetermined silica gel, and based on this knowledge, we have completed the present invention. .

That is, the present invention uses ω linear low density polyethylene (hereinafter, (
a) It is called a component. ) 100 parts by weight (b) melting point 60-1
Fatty acid amide at 20°C and/or average particle size 1-2
This is a linear low-density polyethylene resin composition containing 0.1 to 1.5 parts by weight of silica gel (hereinafter referred to as component (b)) having a diameter of 0 μm and a pore volume of 2.0 M1777 or less.

The linear low density polyethylene which is the component (a) of the present invention serves as the base of the resin composition of the present invention.

Linear low density polyethylene is so-called LLDPE, and is composed of ethylene and a small amount (about 0.2 to 20 mol%) of other α-olefins, such as propylene and butene.
1, Penten-1. Hexene-1゜4-methylpentene-1, octene-1, decene-1, etc. are copolymerized in the liquid phase or gas phase under conditions similar to those used in the production of conventional high-density polyethylene (HDPFi). It is manufactured by The density of this linear low-density polyethylene is usually 0.910 to 0.9609/about 8, and contains 1 to 60 short aliphatic fractions per 1000 carbon atoms in the chain. It is.

Next, the component (1-,) is a fatty acid amide having a melting point of 60 to 120°C and/or a silica gel having an average particle size of 1 to 20 μm and a pore volume of 2.01 d19 or less.

Here, the fatty acid amide may be any fatty acid amide having a melting point of 60 to 120°C, preferably 70 to 90°C, and is not particularly limited. If the melting point of the fatty acid amide used here is less than 60°C, the haze of the film of the resulting composition will increase and the transparency will be impaired, and if the melting point exceeds 120°C, blocking of the film will occur. This is not desirable because the

Specific examples of fatty acid amides with a melting point of 60 to 120°C include:
Erucic acid amide, stearic acid amide.

Oleic acid amide °, Behenic acid amide, N-Stearic acid amide, N-Stearyl caprylic acid amide, N-
Stearyl lauric acid amide, N-stearyl stearic acid, N-stearyl behenic acid amide, N-oleyl oleic acid amide, N-oleic behenic acid amide,
Examples include N-butyl erucamide, N-octyl erucamide, and N-lauryl erucamide.

The silica gel has an average particle diameter of 1 to 20 μm, preferably 3 to 10 μm, and a pore volume of 2.0 μm.
0 Go/g or less, preferably (L3 to 1.7 Ill/11
are used. When the average particle diameter is less than 1μ,
The dispersibility of silica gel is insufficient, and if it exceeds 20μ, haze increases and transparency is impaired, resulting in poor practicality. Also, the pore volume is 2.0 ml/f! It is not preferable to use a substance exceeding 100% because the dispersibility of the silica gel decreases. Note that the value of pore volume was measured by the BET method.

In the present invention, the component (b) may be any one of the above-mentioned fatty acid amide and silica gel, or a combination of both.

The blending ratio of component) and component (b) in the present invention is 0.1 to 1.5 parts by weight, preferably 0.2 to 0.8 parts by weight of component (b) per 100 parts by weight of component (a). Should be parts by weight. (b) When the blending ratio of component is less than 0.1 part by weight,
The slip and anti-blocking properties of the film of the composition will be insufficient, and if it exceeds 1.5 parts by weight, the transparency and heat-sealing properties of the film will decrease, which is not preferable. In addition, when using two components of fatty acid amide and silica gel as component (b), the blending ratio is the former: the latter = 1:3 ~
The ratio may be 3:1, and it is particularly preferable to use approximately the same amount.

The resin composition of the present invention consists of the above-mentioned components (a) and (b), and further contains metal oxides such as calcium stearate and zinc stearate; an antistatic agent; a weathering agent; a blowing agent; a pigment, etc. Other additives may also be blended.

The resin composition of the present invention can be obtained by blending predetermined amounts of each of the above-mentioned components and thoroughly kneading the mixture by a combined dry/wet/melt mixing method, a multistage melt mixing method, a simple melt mixing method, or the like. In addition, the crosstalk is Banbury mixer, co-kneader, extruder,
This can be carried out using a twin-screw kneader or the like.

The resin composition of the present invention thus obtained is used after being molded into an appropriate shape, such as a film, by various molding methods such as extrusion molding and injection molding.

A film formed from the resin composition of the present invention has excellent sliding properties, blocking properties, etc., and also has good transparency, heat sealability, mechanical properties, etc. Furthermore, there is almost no wrinkles during secondary processing such as printing, slitting, and bag making during film production, resulting in high productivity.

As described above, the linear low-density polyethylene resin composition of the present invention has various uses, particularly as packaging materials such as packaging bags.
Alternatively, it can be effectively used as an agricultural film.

Next, the present invention will be explained in detail with reference to examples.

Examples 1 to 7 and Comparative Examples 1 to 7 Each component shown in Table 1 was blended in a predetermined amount, and mixed in a twin-screw kneader for 2 hours.
The mixture was kneaded at 00°C to obtain a linear low density polyethylene resin composition.

The obtained resin composition was extruded into a tubular shape through a die (9 die 120 mφ, lip clearance 2.0 m) at an extrusion temperature of 190°C using an extruder (50 mm φ) to a thickness of 30 μm.
Make a film of this thing about haze, slippage,
Blocking property and heat seal strength were measured. The results are shown in Table 1.

Note that each measurement was performed using the following method.

111 Haze Compliant with ASTM D 1003 (2) Sliding Compliant with ASTM D 1894 (3) Blocking property After applying the top and bottom peeling method and applying a load of 9 to 9 on the film surface and leaving it at a temperature of 60 ° C for 3 hours, Place it in the blocking measurement chuck and peel it off using an autograph (
Measure the maximum value when the tensile speed is 200 x 1/10" 7 minutes) (4) Heat seal strength 4 x 20 cm test piece is crimped with heat seal width of I x 2.5 cm F under heat seal condition 2 kg/cm", 1
After sealing for seconds, it was left for 30 minutes. Then, measure the tensile strength (g/2.5cm) *l: P E-1'' Density 0.9209/crn
3. Copolymer octene-1, linear low-density polyethylene with 14 branches: PE-2--density 935g/me 3, copolymer hexene-1, linear low-density polyethylene with 6 branches *2 : Mu-1... Erucic acid amide A with a melting point of 79-83°C -2-... Oleic acid amide A- with a melting point of 72-77°C
3... Stearic acid amide with a melting point of 100 to 105°C A-4 @ Ethylene bisstearic acid amide with a point of 140°C or higher *3: B-1... Average particle diameter 4.0 μ, pore volume 0,
44 go/g B-2...Average particle size 3.5μ, pore volume 0.44 go/9

Claims (3)

[Claims] (1) Melting point 60 in 100 parts by weight of linear low density polyethylene
~120°C fatty acid amide and/or average particle size 1
A linear low-density polyethylene resin composition containing 0.1 to 1.5 parts by weight of silica gel having a pore volume of ~20 μ and a pore volume of 2.0 ml/g or less. (2) The resin composition according to claim 1, wherein the fatty acid amide is erucic acid amide, oleic acid amide, stearic acid amide, behenic acid amide, or a derivative thereof. (3) The resin composition according to claim 1, wherein the silica gel has an average particle diameter of 3 to 10 μm and a pore volume of 0.3 to 1.7 ml/g.