JPS6044510A - Amorphous vinylidene halide copolymer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an amorphous vinylidene halide copolymer, and more particularly, to an amorphous vinylidene halide copolymer consisting of one unit of a specific composition. It relates to vinylidene copolymers.

Prior Art Conventional vinylidene halide copolymers have been essentially crystalline copolymers. These copolymers have generally been processed into films by extrusion processing or DL cast from solutions or emulsified emulsions dissolved in solvents, and have been applied to a wide range of applications. The main uses are food packaging films that utilize oil resistance, water vapor barrier properties, and oxygen barrier properties. For applications requiring oil resistance and barrier properties, vinylidene halide copolymers, especially vinylidene chloride copolymers, are economical and versatile. For the oil resistance and barrier properties of this vinylidene chloride copolymer, it is preferable that the copolymer is essentially crystalline, and vinylidene halide copolymers including known vinylidene chloride copolymers are crystalline. Met.

On the other hand, crystalline vinylidene halide copolymers have the drawbacks of poor processability (for example, extrusion processability), solubility in solvents, and post-emulsification stability over time. Conventionally, it was necessary to use a plasticizer to improve extrusion processability, an expensive solvent to improve solubility, and a large amount of post-emulsifier to maintain stability over time. Ta.

For example, even if extrusion processability is improved by using a plasticizer, the plasticizer will migrate to the surface of the film during use, contaminating the packaged contents such as food. The disadvantage was that there was a risk of At the same time, films containing plasticizers had the disadvantage that their barrier properties were significantly lower than films without plasticizers. That is, a plasticizer is indispensable for industrial extrusion film formation, and there has been a contradictory demand that a plasticizer is unnecessary in view of the film's barrier properties and non-adherence to foods.

As one specific example can be seen in JP-A-55-129439, conventional vinylidene halide resins, especially vinylidene chloride resins, place emphasis on barrier properties. All of them were crystalline.

The more we place importance on high IJ properties, the more we strive to improve the extrusion processability of the highly crystalline vinylidene chloride resin by adding plasticizers to the highly crystalline vinylidene chloride resin containing high vinylidene chloride content. were piled up. On the other hand, efforts to lower the degree of crystallinity or to make it amorphous have been abandoned as they have little practical meaning because they reduce the barrier properties of vinylidene chloride resin.

Therefore, the composition of the vinylidene chloride-vinyl chloride copolymer described in this publication is a copolymer containing 72.05 mol to 92.5 mol of vinylidene chloride, and has a crystallization temperature of 105°C or higher. It is a crystalline vinylidene chloride resin.

The film formed from the resin described in the above publication has excellent barrier properties and is extremely useful only for food packaging. However, a plasticizer is indispensable for film formation on an industrial scale, and according to Example 1, a plasticizer of 8 weight percent is used.

Vinylidene chloride resins aimed at barrier properties are all crystalline and have a composition that has a crystallization melting point.

Another example is the use of conventional crystalline vinylidene chloride copolymers to meet the demand for closed foamed vinylidene halide copolymers, particularly vinylidene chloride copolymers, for flame-retardant insulation. When trying to manufacture a body, the following 2
There were two difficulties.

(1) Due to the low solubility of physical blowing agents (e.g. Freon 11, 12, etc.) and the low miscibility of chemical blowing agents (e.g. azobis compounds), only foams with low expansion ratio/continuous foaming can be obtained. 2) Difficulty in controlling foaming due to extremely narrow dulling point due to drastic changes in melt viscosity during the foaming process.

As another example, in response to the demand for flame retardant combustible thermoplastic resin, for example, in flame retardant polystyrene resin,
Attempts have been made to polymer blend vinylidene chloride copolymers, but the reality is that they have not been put to practical use due to the miscibility of crystalline vinylidene chloride copolymers.

As described above, although vinylidene halide copolymers have various properties such as barrier properties, flame retardance, high frequency sensitivity, and dielectric properties that are unparalleled, their processability has been a bottleneck. Currently, it is only used for limited purposes.

Purpose and Structure of the Invention As a result of extensive research, the present inventors have succeeded in providing an amorphous vinylidene halide copolymer that maintains the various properties of vinylidene halide copolymers and has greatly improved processability. Ta.

That is, the present invention provides an amorphous vinylidene halide comprising 1 to 87 mol of at least one type of 710 vinylidene halide (4) and 13 to 99 mol of at least one monomer (B) copolymerizable with the component (4). A copolymer is provided.

Detailed Description of the Structure and Effects of the Invention The amorphous vinylidene halide copolymer according to the present invention has virtually no crystallinity or crystallization temperature, and its potential applications are extremely wide, such as Applications include fuel agents, barrier molded products, adhesives, electrical parts, additives for various blends, and composite materials.

Specific potential applications include unplasticized barrier films,
The invention is not limited to the potential applications described herein, including bottles, tubes, flame retardant foams, high frequency adhesives, barrier composite sheets, etc. The key to the present invention is to provide an amorphous vinylidene halide copolymer with excellent processability that substantially retains all the excellent properties of a crystalline vinylidene halide copolymer.

Below, specific elements of the invention will be explained in detail and examples thereof will be shown, but it goes without saying that these are not intended to limit the content of the invention.

Vinylidene halide component (4
), vinylidene fluoride, vinylidene chloride, and vinylidene bromide can be used.

Preferably vinylidene fluoride or vinylidene chloride,
More preferred is vinylidene chloride. Vinylidene chloride is easy to handle and economical.

It goes without saying that not only 61 types of these vinylidene halide components (A) but also a mixture of two or more types may be used.

As the monomer group component (B) that can be copolymerized with the vinylidene halide component (4), an α-monosubstituted unsaturated ethylenic monomer, an unsaturated carboxylic acid dical? It can be made by using phosphoric acids and their acetamide and ester monomer components. Preferably, the α-monosubstituted unsaturated ethylenically monomer is vinyl acetate, vinyl crotonate, vinyl methyl ether, acrylonitrile, meta-acrylonitrile, unsaturated carbon, etc. Acrylic acid, methacrylic acid, itaconic acid, maleic acid, faric acid, maleic anhydride, acrylic acid amide, methyl acrylate,
Ether acrylate, butyl acrylate, ethylhexyl acrylate, allyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylhexyl methacrylate, methacrylic acid amide, hydroxyethyl acrylate, glycidyl methacrylate are used.

More preferably, the α-substituted unsaturated ethylenic monomer is vinyl acetate, acrylonitrile, unsaturated carboxylic acid, dicarboxylic acid and their acid amides, and the ester monomer component is acrylic acid, methacrylic acid, maleic anhydride. , methyl, ethyl, butyl, ethylhexyl acrylate, methyl methacrylate, and acrylamide are easily available industrially.

Needless to say, it is composed of a mixed component of one or more selected from these components (B).

As a crosslinking component, an unsaturated carboxylic acid derivative having two or more unsaturated groups, an unsaturated carboxylic acid derivative having an allyl group, or an unsaturated carboxylic acid derivative having a glycidyl group that crosslinks by ring opening by heating. may also be used to adjust the molecular weight. Such crosslinking monomers are also advantageously used when producing bead foams. As an economically preferable crosslinking agent, an alkyl ester of acrylic acid at both ends of polyethylene glycol or glycidyl methacrylate can be used.

The composition of the vinylidene halide component (5) and the monomer component (B) that can be copolymerized with the component (4) is as follows: 1 mole of the vinylidene halide component monomer (91%). The monomer of component (B) is 13 molar or more and 99 molar or less. Preferably (A) component monomer 1 is 15 mol% or more and 90 mol% or less, more preferably (A) component monomer 20 mol% or more and 80 mol% or less, (B) component monomer 20 mol% or more, The molar ratio is preferably 80 molar, most preferably the (A) component monomer is 20 molar or more and 70 molar or less, and the (B) component monomer is 30 molar or more and 80 molar.

The maximum content of component (4) varies depending on the monomer of component (B). When the component monomer (4) is vinylidene chloride and the component monomer (B) is methyl acrylate, the vinylidene chloride component can be contained up to 87 molar percentage or less in order to be an amorphous copolymer. Further, when the component monomer (4) is vinylidene chloride and the component monomer (B) is vinyl chloride, it is preferable that the vinylidene chloride component does not exceed 65 moles.

When the vinylidene halide component monomer is less than 1 mole 7, various properties attributable to the vinylidene halide are substantially lost, which is not preferable.

On the other hand, if the vinylidene halide component monomer exceeds 87 molar ratio, the copolymer is substantially crystalline and has a structure different from that of the copolymer of the present invention. Out of range.

Known suspension polymerization is most suitable for producing the copolymer of the present invention. In the suspension polymerization method, monomer oil droplets are suspended in water using an organic suspending agent (e.g., methylcellulose, polyvinyl alcohol, alginate, etc., or an inorganic suspending agent, such as colloidal aluminum hydroxide, nickel hydroxide, etc.). A method of suspending and polymerizing the polymer is industrially useful.

As a method for producing the amorphous vinylidene halide copolymer, suspension polymerization using methylcellulose as a suspending agent is preferred.

A small amount of methylcellulose remaining in the obtained polymer is preferable because it does not have an adverse effect on the subsequent processability and physical properties of the molded product.

,]? IJ Mama - To remove trace amounts of methylcellulose remaining inside or in molded products, dissolve the polymer or molded product in tetrahydrofuran, add an aqueous solution of hydroiodic acid, concentrate the generated methyl iodide and propyl iodide, and turn it into a gas. Measure by chromatography. This analytical method can analyze trace amounts of temethylcellulose with high sensitivity for Tellimer or molded articles.

As the radical initiator, any oil-soluble radical initiator that can be dissolved in a monomer and generate a diradical upon thermal decomposition can be used. They are appropriately selected and used depending on the polymerization temperature, polymerization time, and difficulty in removing polymerization heat. For example, in order to polymerize at a relatively low temperature, azobismethoxydimethyl R'1
In order to polymerize nitrile, diisopropyl, peroxydicarbonate, etc. at a relatively high temperature, well-known compounds such as azobisisobutyronitrile and lauryl oxide can be used. The terminals of the decomposition products of these radical initiators are preferably non-functional groups, especially since they do not discolor due to heat during extrusion processing.

The degree of crystallinity of the copolymer of the present invention is measured as follows. That is, 10 μm of the copolymer was placed in an aluminum ram container, fixed in the measurement cell of a differential calorimeter (DSC), and 2
The temperature is raised from -50°C to 220°C at a constant heating rate of 0°C/min, and the exothermic or endothermic differential curve is recorded as a function of differential calorific value and temperature.

In this temperature range, at least one melting peak is observed in the crystalline vinylidene halide copolymer, and this peak area is caused by crystal melting and is converted into crystallinity. The amorphous ha-rhodanized copolymer is completely different from the crystalline vinylidene halide copolymer, no melting peak is observed, and therefore the degree of crystallinity can be clearly calculated as O. Since no crystals are formed in the amorphous vinylidene halide copolymer, a melting peak corresponding to a thermodynamic second-order transition does not appear, but a glass transition temperature corresponding to a thermodynamic second-order transition is observed.

In addition to measuring the degree of crystallinity and crystallization temperature by DSC, as a measure to identify the amorphousness of the copolymer, three or more monomers of the vinylidene halide component in the copolymer are sequentially measured. There is a proportion (a proportion greater than or equal to the Triad component) that forms the N.
It is calculated based on the measurement chart by MR. Tri a
The ratio of the d component or higher must be 60 or less; if it exceeds this, it is an extremely slow process, but it is not preferable for a crystalline vinylidene halide copolymer to form crystals, for example, on a monthly basis. The ratio of Triad components or higher is preferably 50% or less, and more preferably 45% or less.

The molecular weight of the copolymer of the present invention is determined by dull emission chromatography. The molecular weight is preferably 1000 or more, more preferably 1oooo or more.

If the molecular weight is less than 1,000, it becomes oily, glue-like, or paste-like, and is not practical as a molded product.

However, for example, glycyl methacrylate modified copolymers are crosslinked by heat treatment and have a molecular weight of 1000 or more when put into practical use, so it is difficult to include them in the present invention. As another example, the copolymer formed by combining methacrylic acid, acrylic acid, and maleic anhydride is
For example, Na*Ca.

By blending acetates such as Mg and At, polymetallic crosslinking occurs by melting, and when it is put into practical use, the molecular weight is 1000.
Since this is the above, it is included in the present invention.

As explained above, the amorphousness of the copolymer according to the present invention is determined by the level of vinylidene halide (CA) and the ratio of Tri ad of vinylidene halide (4) derived from the comonomer (B) used. It depends on both.

For example, if component (B) is vinyl chloride, the level of component (4) may be up to 65 molt;
Most preferably, the r i ad ratio is up to 55 inches.

As another example, when component (B) is an acrylic comonomer such as methyl acrylate, ethyl acrylate, butyl acrylate and methyl methacrylate, component (
Tri of component (4) at a level of up to 87 mol% of component (4)
Most preferred is an ad ratio of up to 60%.

EXAMPLES The present invention will be described in detail below, but it goes without saying that the scope of the present invention is not limited to these Examples.

Example-1 Vinylidene chloride and methyl acrylate or butyl acrylate are mixed at various composition ratios as shown in Table 1 to form a monomer mixture of 1 part and 9 parts, and zoisoprobyl peroxydicarbonate (IPP) is prepared. Immediately after dissolving 2 g of methyl cellulose (ME manufactured by Dow Chemical Company, USA),
THOCEL K4M) 1.5 g, ethylenediamine 0.1# dissolved in water? The monomer mixture was charged into a polymerization vessel containing 1500 g of ti[1,500 g] under reduced pressure. When the seven-mer mixture was charged under reduced pressure, it was stirred using a stirrer equipped with a Faudler-type stirring blade at a stirring speed of 375 rpm.

For each monomer mixture, starting the polymerization temperature at 30°C,
Polymerization was carried out at 0°C for 4 hours while raising the temperature to 40°C at a rate of 1°C/hour, and then polymerization was carried out without raising the temperature to 55°C at a rate of 1.5°C/hour. The polymerization was completed over a period of 24 hours. The polymerization rates of all copolymers were 95% to 98%. These common electric bodies are 1
Table 1 shows the results of the tensile strength and elongation of a 25-width, 100-μ film that was extruded at 160° C. using a Brabender extruder with a diameter of an inch. It can be seen that a semi-hard film can be obtained from a soft film at room temperature.

For comparison, a copolymer prepared using 92 mol vinylidene chloride and 8 mol methyl acrylate under the same polymerization conditions as above was tried to be extruded under the same conditions as above, but no film was obtained and the extrusion pattern was degraded. However, a semi-molten material 75E+j was deposited on the rotor of the screw, and some of it was decomposed and turned brown.

Example 2 A monomer mixture consisting of 70 mol of vinylidene chloride and 30 mol of methyl methacrylate was subjected to suspension polymerization in the same manner as in the polymerization method of Example 1. The polymerization rate was 98 V, and in order to remove residual monomers, the suspension in water was subjected to a reduced pressure treatment at 95° C. for 4 hours and a water head of 30 degrees after polymerization.

This copolymer alone, or 20 parts of this copolymer and a crystalline vinylidene chloride copolymer (92 moles vinylidene-8
A composition was prepared by blending 80 parts of moltimethyl acrylate. To 100 parts of these resins, 10 parts of the blowing agent Freon-11, 1 part of Merck, and 0.0 parts of stearic acid.
Add 1 part and leave it in a sealed container overnight to prepare Freon-1.
1 was equilibrated into an amorphous vinylidene chloride copolymer.

This composition containing a blowing agent was extruded from a melt extruder heated to 160°C through a die of 1/10 mm. Table 2 shows the density of this foamed extrudate.

For comparison, a composition in which the above-mentioned crystalline vinylidene chloride copolymer was subjected to equilibrium absorption of Freon-11 was extruded under the same conditions, but no foaming occurred.

EXAMPLE 3 A monomer mixture of 1 mol consisting of 60 mol of vinylidene chloride, 20 mol of methyl acrylate, and 20 mol of vinyl acetate was polymerized at 45 DEG C. for 60 hours using a 4-part polymerizer. The radical initiator used was IPP with a concentration of 0.0% relative to the monomer.
5% by weight, 0.3% by weight of methylcellulose as a suspending agent, and 1500.9% of water were used. In order to remove residual monomers and radical initiators, the mixture was treated under reduced pressure at 95° C. for 4 hours in the presence of water. The polymerization rate was 96%, and the beads were spherical transparent copolymer beads with a particle size range of 80 to 300 μm.

Example 4 1 kg of a mixture of 92 mols of vinyl chloride, 40 mols of methyl acrylate, and 10 mols of methacrylic acid was polymerized under the polymerization conditions and polymerization recipe of Example 1. The polymerization rate was 92%, and the particles were spherical, transparent copolymer beads with a particle size range of 50μ to 400μ.

Example-5 (vinyl chloride 92 ml, methyl acrylate) 39.
Mixture 1 of 9 molar parts and 0.1 molar parts of allyl acrylate
9 was polymerized using the polymerization conditions and polymerization recipe of Example-1. The polymerization rate is 97% and the particle size range is 80μ~250
They were spherical transparent copolymer beads of μ. This copolymer could be shaped under compression molding conditions of 180'CXZmin x 100kg/cWL, but the compression molded sheet returned to its original particle size when heated at 50°C.

Below margin

Claims (1)

[Claims] 1. At least one kind of vinylidene halide 1-87
It has a non-functional polymer terminal group consisting of 13 to 99 moles of at least one monomer (B) copolymerizable with molti and the vinylidene halide component (4), and has a crystallinity of 0 and a crystallization temperature. an amorphous vinylidene halide copolymer having no halogenated vinylidene component (4), the amorphous copolymer containing 60 or less by weight sea fences consisting of three or more consecutive units of the vinylidene halide component (4). Amorphous vinylidene halide copolymer. 2. The copolymer according to claim 1, wherein the vinylidene halide component (I) is at least one member selected from the group consisting of vinylidene chloride, vinylidene fluoride, and vinylidene bromide. 3. Is the monomer component (B) α-monosubstituted unsaturated ethylenic monomers, unsaturated carboxylic acids, or radicals? 3. The copolymer according to claim 1 or 2, which is at least one member selected from the group of acids and ester monomers thereof. 4. At least one type of vinylidene halide (A) 1-
87 molti and the above-mentioned vinylidene chloride component (4)
At least one monomer copolymerizable with (B) 13~
A film, sheet, foam or molded article mainly comprising an amorphous nologonated vinylidene copolymer of 99 mol.