JPH1052870A - Biodegradable resin net - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress a decrease in physical properties and to hold a function as a net by adding a specific amount of surface-treated filler to biodegradable aliphatic polyester resin. SOLUTION: 10 to 150 pts.wt. filler is added to 100 pts.wt. biodegradable aliphatic polyester resin. The filler is obtained by surface treating at least one selected from among calcium carbonate, clay, talc, aluminum hydroxide and magnesium hydroxide with titanate coupling agent or treating at least one type selected from among silica, ceramic balloon, glass balloon and glass bead with epoxy silane coupling agent. The polyester resin is a mixture of polyhydric carboxylic acid such as malonic acid, succinic acid and their anhydrides with one or more types of condensation polymer of polyhydric alcohol such as ethylene glycol, propylene glycol and a ring-opening polymer of cyclic ester of lactide or ε-caprolactone.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention provides a biodegradable resin net that is useful as a packaging material for vegetables and fruits, is inexpensive, has excellent rigidity, feel, and heat sealability, and decomposes naturally when buried in soil after use. .

[0002]

2. Description of the Related Art Conventional biodegradable polyester resins have a high price of 900 to 2,000 yen / kg, which makes it difficult to use them as the above packaging materials. However, physical properties,
In particular, the elongation was remarkably reduced, and it became brittle, so that practicality as a net could not be expected.

[0003]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a biodegradable material capable of suppressing a decrease in physical properties and maintaining a function as a net even when the price is reduced by increasing the amount of filler. It is intended to provide a net made of a conductive resin.

[0004]

A biodegradable resin net according to the present invention is obtained by adding 10 to 150 parts by weight of a surface-treated filler to 100 parts by weight of a biodegradable aliphatic polyester resin. It is. This filler includes calcium carbonate,
At least one selected from clay, talc, aluminum hydroxide and magnesium hydroxide, surface-treated with at least one selected from titanate coupling agents, aluminum coupling agents, acetylene glycol and derivatives thereof; silica, At least one selected from ceramic balloons, glass balloons and glass beads is surface-treated with an epoxy silane coupling agent; or starch is surface-treated with at least one selected from acetylene glycol and its derivatives. Is preferably used. The biodegradable resin net made of these materials can be highly filled and has a good balance of physical properties.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The biodegradable aliphatic polyester resin used in the present invention may be any one having biodegradability, and specifically, malonic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, fumaric acid, maleic acid , Dodecanoic acid, malic acid, tartaric acid, polycarboxylic acids such as citric acid and anhydrides thereof, and ethylene glycol, propylene glycol, butanediol, hexanediol, octanediol, decanediol, glycerin, trimethylolpropane, etc. Polycondensation products with polyhydric alcohols, ring-opening polymers of cyclic esters such as lactide and ε-caprolactone, which are cyclic dimers of lactic acid, and condensation polymers of hydroxy acids such as lactic acid, hydroxybutyric acid, and hydroxyvaleric acid. And used as one kind or a mixture of two or more kinds.

The filler includes an inorganic filler and an organic filler. Examples of the inorganic filler include calcium carbonate, clay, talc, aluminum hydroxide, magnesium hydroxide, silica, ceramic balloon, glass balloon, and glass beads. Examples of the organic filler include starches such as grains such as wheat and corn, and potatoes such as potato, sweet potato, tapioca and the like. These fillers are used as one kind or a mixture of two or more kinds, and the properties can be complemented by mixing.

[0007] Of these, regarding calcium carbonate,
If the average particle size is 5-6 μm or less, heavy, light,
Although any of colloids may be used, it is preferable that the surface is not treated with a fatty acid or the like. The difference in specific surface area depending on the particle size affects the viscosity and physical properties at the time of molding. Therefore, it is desirable that the amount of calcium carbonate having a small particle size be smaller than the amount of calcium carbonate having a large particle size.
Clay, talc, aluminum hydroxide, magnesium hydroxide or silica having the same particle size and surface treatment as calcium carbonate are also used.

The ceramic balloon, glass balloon or glass beads may have a particle size of about 100 μm or less. These spherical fillers have a small increase in viscosity at the time of filling. In particular, since ceramic balloons and glass balloons are hollow, the specific gravity is small, and the addition of the biodegradable resin also reduces the specific gravity, which is advantageous in terms of cost. In addition, when a round ceramic balloon or glass balloon is used, no directionality appears in the added biodegradable resin, so that there is an advantage that a product having no directionality can be obtained at the time of molding.

[0009] Starch takes various shapes depending on the type of material, the contents of amylose and amylopectin, the degree of polymerization thereof are different, and the particle size varies, but the average particle size is 100 µm.
It is sufficient if it is about the following.

As a surface treatment agent for these fillers, epoxy-based silane coupling agents (Table 1) are preferable for ceramic balloons, glass balloons, glass beads and silica, and titanate-based cuppers are used for other inorganic fillers. Suitable are ring agents (Table 2), aluminum coupling agents (Table 3) or acetylene glycol and its derivatives (Table 4). Among these, the epoxy-based silane coupling agent and the titanate-based coupling agent take a form in which the inorganic portion of each coupling agent is oriented toward the inorganic filler and the organic portion is directed toward the resin.
That is, a structure in which an inorganic substance is wrapped with an organic substance is obtained, uniform dispersion becomes possible, and a decrease in physical properties can be minimized due to interaction with the resin.

[0011]

[Table 1]

[0012]

[Table 2]

[0013]

[Table 3]

[0014]

[Table 4]

On the other hand, acetylene glycol or a derivative thereof is preferred as a surface treatment agent for starch. Acetylene glycol is a powerful surfactant, which is oriented to -OH groups in starch, and the organic portion is directed toward the resin, so that uniform dispersion and interaction in the resin occur, thereby reducing the decrease in physical properties. Conceivable. Dispersing an organic powder such as starch uniformly in a resin cannot be expected from a general surface treatment agent, and is a great effect of acetylene glycol.

Regarding the method of surface treatment of these fillers, any method such as a wet method (a method by hydrolysis), a dry method, and an integral blend on a mixing roll can be used. The addition amount of the surface treating agent in the range of 0.5 to 5 PHR is sufficient. If this is less than 0.5 PHR, the effect as a surface treatment agent cannot be expected so much, and if it exceeds 5 PHR, it becomes expensive and economically inferior.

[0017] The biodegradable resin net of the present invention requires the surface-treated filler in the range of 10 to 150 parts by weight based on 100 parts by weight of the biodegradable aliphatic polyester resin described above. If it is less than 10 parts by weight, viscosity adjustment by adding filler, fluidity, adhesion,
The effect on the strength and the like is reduced, and if it exceeds 150 parts by weight, the viscosity is too high, and the moldability and physical properties are remarkably reduced, and the practicality is lost.

A biodegradable aliphatic polyester resin to which a surface-treated filler is added must not normally cause photodegradation during use. For example, an ultraviolet absorber,
An antioxidant and the like may be added, and a pigment for coloring and a plasticizer for imparting flexibility may be added.

Further, the biodegradable aliphatic polyester resin usually has a calorific value of about 1/2 that of polyethylene or the like, but the above-mentioned biodegradable aliphatic polyester resin to which a surface-treated filler is added has a calorific value. Is even less (1/3 to 1 /
4) There is no problem in incineration treatment in an incinerator, and when buried with additional starch, etc., a secondary effect that decomposition by microorganisms is further promoted can be expected.

[0020]

EXAMPLES The present invention will be specifically described below based on examples and comparative examples, but the present invention is not limited to the description of the examples. Example 1 Aliphatic polyester resin: Bionole 3010 (manufactured by Showa Polymer Co., Ltd., trade name, copolymer of 1,4-butanediol and succinic acid and / or adipic acid) 100 parts by weight, as a titanate coupling agent 120 parts by weight of heavy calcium carbonate having an average particle diameter of 2 μm, 2 parts by weight of stearic acid, and calcium alkylbenzenesulfonate: 7764 (trade name, manufactured by Akishima Chemical Industry Co., Ltd.) to which 1 part by weight of tetraisopropylbis (dioctylphosphite) titanate is added. 3 parts by weight,
The resin was kneaded with a mixing roll at 90 ° C. until 5 minutes after the resin was melted, and was taken out in a sheet form. This was placed in a mold having a thickness of 2 mm and pressed at 130 ° C. for 5 minutes to obtain a sheet having a thickness of 2 mm. A punch test sample was prepared from this sheet using a No. 2 dumbbell specified in JIS, and a tensile test was performed at a speed of 200 mm / min. The strength, elongation, and 100% modulus were measured. The results are shown in Table 5. Was.

On the other hand, the sheet-like material is cooled to room temperature and then pulverized to produce pellets. Using the pellets, the cylinder temperature is 140 to 160 ° C. by a single screw extruder equipped with a net extrusion die. Die temperature: 160-170 ° C, a net having a wire diameter of 0.3 mm, a thickness of 0.6 mm and a diameter of 100 mm was extruded. It was a net that could be molded without problems and could withstand use.

Example 2 Aliphatic polyester resin: Bionole 3010 (supra) 100
Parts by weight and ethylene oxide adduct of acetylene glycol: Surfynol 440 (trade name, manufactured by Nissin Chemical Industry Co., Ltd.)
Corn starch with an average particle size of 15 μm added with 1 part by weight 1
00 parts by weight (manufactured by Nippon Flour Milling Co., Ltd.) were kneaded with a mixing roll at 90 ° C. until 5 minutes after melting of the resin. This was taken out in the form of a sheet, a punch test sample was prepared in the same manner as in Example 1, and the same measurement was performed. The results shown in Table 5 were obtained. The sheet was cooled to room temperature and then pulverized to produce pellets. Using the pellets, a net having the same dimensions as in Example 1 was produced. It was a net that could be molded without problems and could withstand use.

Example 3 Aliphatic polyester resin: Bionole 3010 (supra) 100
Parts by weight, high molecular weight epoxy silane coupling agent: MA
C2101 (manufactured by Nippon Unicar, trade name) A glass balloon having an average particle diameter of 50 μm to which 1 part by weight is added: X-39 (manufactured by Asahi Glass Co., Ltd., trade name) 60 parts by weight, stearic acid 2 parts by weight, and calcium alkylbenzene sulfonate ： 7764 (see above)
3 parts by weight were kneaded with a mixing roll at 90 ° C. until the resin melted for 5 minutes. This was taken out in the form of a sheet, and
A sample for a punching test was prepared in the same manner as described above, and the same measurement was performed. The results shown in Table 5 were obtained. The sheet was cooled to room temperature and then pulverized to produce pellets. Using the pellets, a net having the same dimensions as in Example 1 was produced. It was a net that could be molded without problems and could withstand use.

When the net of the present invention obtained in each of the above examples was buried in humus and allowed to stand in a constant temperature room at 23 ° C. × 55% RH, decomposition was considerably advanced after three months.

Example 4 Aliphatic polyester resin: Bionole 3010 (supra) 100
Parts by weight and γ as an epoxy-based silane coupling agent
-Burned clay with an average particle size of 0.2 µm added with 1 part by weight of glycidoxypropyltrimethoxysilane: Burgess ^# 30
(Berges Pigment, trade name) 100 parts by weight, 2 parts by weight of stearic acid and 3 parts by weight of calcium alkylbenzenesulfonate: 7764 (described above) are kneaded with a mixing roll at 90 ° C. until 5 minutes after melting of the resin. Then, a sample for a punching test was prepared in the same manner as in Example 1, and the same measurement was performed. The results shown in Table 5 were obtained.

Example 5 Aliphatic polyester resin: Bionole 3010 (supra) 100
Aluminum hydroxide having an average particle diameter of 1 μm, to which 1 part by weight of acetoalkoxyaluminum diisopropylate as an aluminum coupling agent is added.
(Manufactured by Showa Denko KK, trade name) 100 parts by weight, stearic acid 2
Parts by weight and calcium alkylbenzenesulfonate:
7764 (described above), 3 parts by weight were kneaded with a mixing roll at 90 ° C. until 5 minutes after the resin was melted, taken out in a sheet form, and a punching test sample was prepared in the same manner as in Example 1. As a result, the results shown in Table 5 were obtained.

Comparative Example 1 In the same manner as in Example 1, except that the heavy calcium carbonate was not subjected to the titanate treatment, the mixture was uniformly kneaded with a mixing roll. This was taken out in the form of a sheet, a punch test sample was prepared in the same manner as in Example 1, and the same measurement was performed. The results shown in Table 5 were obtained. The sheet was cooled to room temperature and then pulverized to prepare pellets. Using the pellets, an attempt was made to extrude a net having the same dimensions in the same manner as in Example 1, but the net was cut and could not be formed.

Comparative Example 2 The same procedure as in Example 2 was repeated except that the corn starch was not treated with acetylene glycol. This was taken out in the form of a sheet, a punch test sample was prepared in the same manner as in Example 1, and the same measurement was performed. The results shown in Table 5 were obtained.
The sheet was cooled to room temperature and then pulverized to prepare pellets. Using the pellets, an attempt was made to extrude a net having the same dimensions in the same manner as in Example 1, but the net was cut and could not be formed.

Comparative Example 3 The procedure of Example 3 was repeated, except that the glass balloon was not treated with the epoxy silane coupling agent. This was taken out in the form of a sheet, a punch test sample was prepared in the same manner as in Example 1, and the same measurement was performed. The results shown in Table 5 were obtained. The sheet was cooled to room temperature and then pulverized to prepare pellets. Using the pellets, an attempt was made to extrude a net having the same dimensions in the same manner as in Example 1, but the net was cut and could not be formed.

[0030]

[Table 5]

Comparative Example 4 Aliphatic polyester resin: Bionole 3010 (supra) 100
8 parts by weight of heavy calcium carbonate having an average particle size of 2 μm, 2 parts by weight of stearic acid, and 7774 parts by weight of a calcium oxide alkyl benzene sulfonate to which 1 part by weight of Surfynol 440 (described above) is added. 3 parts by weight (described above) were kneaded with a mixing roll at 90 ° C. until the resin melted for 5 minutes. This was taken out in the form of a sheet, cooled to room temperature, and then pulverized to produce a pellet. Using this, an attempt was made to extrude a net having the same dimensions in the same manner as in Example 1, but the melt viscosity was too low and it was cut off. Could not be molded.

Comparative Example 5 Aliphatic polyester resin: Bionole 3010 (supra) 100
Parts by weight and ethylene oxide adduct of acetylene glycol: surfynol 440 (supra), 155 parts by weight of heavy calcium carbonate having an average particle size of 2 μm, 2 parts by weight of stearic acid, and calcium alkylbenzenesulfonate: 7764 3 parts by weight (described above) were kneaded with a mixing roll at 90 ° C. until the resin melted for 5 minutes. This is taken out in the form of a sheet, cooled to room temperature and then crushed to produce a pellet,
An attempt was made to extrude a net having the same dimensions in the same manner as in Example 1 using this, but the melt viscosity was too high and the net could not be fused to form.

[0033]

According to the net of the present invention, even if the filler is filled in a large amount, the physical properties are hardly deteriorated. The agent is faster because the microorganisms help the decomposition. In addition, the calorific value when incinerated is about half that of conventional biodegradable resins, and there is an advantage that the incinerator is not damaged.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical indication location // B29K 67:00

Claims (4)

[Claims] 1. A biodegradable resin net characterized in that 10 to 150 parts by weight of a surface-treated filler is added to 100 parts by weight of a biodegradable aliphatic polyester resin. 2. The surface-treated filler comprises at least one selected from calcium carbonate, clay, talc, aluminum hydroxide and magnesium hydroxide, a titanate coupling agent, an aluminum coupling agent, acetylene glycol and 2. The biodegradable resin net according to claim 1, which is surface-treated with at least one selected from derivatives. 3. The surface-treated filler according to claim 1, wherein at least one selected from silica, ceramic balloon, glass balloon and glass beads is surface-treated with an epoxy silane coupling agent. Net made of biodegradable resin. 4. The biodegradable resin net according to claim 1, wherein the surface-treated filler is obtained by surface-treating starch with at least one selected from acetylene glycol and its derivatives.