JPH0291167A - Hydroxylated modified chlorinated polyolefin composition and its production - Google Patents

Abstract

PURPOSE:To make it possible to form a coating composition which can give a coating film which is stable for a long time and is tough by using a specified hydroxylated modified chlorinated polyolefin obtained by chlorinating an acid- modified polyolefin and reacting the product with a polyalcohol. CONSTITUTION:This coating composition is prepared by using a novel hydroxylated modified chlorinated polyolefin obtained by effecting the addition reaction of a polyolefin with an unsaturated carboxylic acid anhydride, chlorinating the product and further reacting the product of chlorination with a polyalcohol. It is preferable that this coating composition further contains an at least one equivalent, per equivalent of the hydroxyl groups, of an isocyanate and/or a polyisocyanate as a curing agent. In the above chlorination, the chlorine content is desirably about 40-60%.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a modified chlorinated polyolefin containing hydroxyl groups, a method for producing the same, and a coating composition using the same.

Specifically, the present invention relates to a new resin that provides a long-term stable and tough coating film and a coating composition using the same.

[Conventional technology]

Chlorinated products such as polyethylene, polypropylene, and ethylene/propylene copolymers are called chlorinated rubber resins, and are generally widely used as anticorrosive paints and architectural primers. The reason for this is that chlorinated rubber paints have excellent adhesion to substrates, quick drying properties, chemical resistance, etc. but,
It is not as good as epoxy or urethane paints in terms of long-term weather resistance and corrosion resistance.

[Problem to be solved by the invention]

Therefore, as a resin that maintains the characteristics of these chlorinated rubber resins and can form stable and strong coating films over a long period of time, we have developed a resin for reactive paints based on the above-mentioned chlorinated polyolefin with hydroxyl groups introduced. After conducting various studies on the production and coating methods thereof, we have arrived at the present invention based on the following coating design concept.

l. A polyolefin modified with a carboxylic anhydride having an unsaturated double bond, such as maleic anhydride, is synthesized from a polyolefin, but one with as low a molecular weight as possible is used in consideration of the workability of the paint. However, one molecule should contain at least one unsaturated carboxylic acid anhydride group.

2. The above modified polyolefin is dissolved in a chlorine-resistant solvent and chlorinated in the presence of a catalyst to synthesize a chlorinated modified polyolefin.

3. Hydroxyl group-containing chlorination is achieved by reacting the chlorinated product of modified polyolefin with a polyhydric alcohol having two or more hydroxyl groups, using some of the hydroxyl groups for esterification and leaving the remaining hydroxyl groups in the polymer. A polyolefin (hereinafter simply referred to as CPO-OH) is synthesized.

4. Prepare a paint by dissolving CPO-OH in an organic solvent and kneading the pigment.

5. Add a predetermined amount of isocyanate or polyisocyanate (at least corresponding to the calculated amount of hydroxyl groups) to the above paint and mix well.

6. Apply this paint with a brush, spray, etc., dry naturally, and crosslink or increase the molecular weight at room temperature.

As a result, it is possible to easily obtain a chlorinated rubber-based paint that has improved coating film toughness, heat resistance, and solvent resistance, and is quick-drying and easy to recoat.

Various methods have already been proposed to improve the drawbacks of chlorinated rubber-based resins. For example, JP-A No. 62-95372 proposes a method of curing with isocyanate a chlorinated polyolefin into which hydroxyl groups have been introduced using a mixed system of chlorinated polyolefin, hydroxyl group-containing acrylic ester, and liquid rubber as an adhesive resin composition. However, in this method, it is difficult to effectively graft acrylic acid monomer to chlorinated polyolefin, so -C=C
We are trying to improve the grafting efficiency by using a liquid rubber with -. Furthermore, JP-A-58-84811 describes a method of reacting a polyol ester of maleic anhydride, which is obtained by reacting maleic anhydride with a polyol, with a polyolefin. This is a method for producing a modified polyolefin that improves the maintenance of equipment, and is different from the present invention in terms of method and field of application, and is also completely different from the embodiment of the present invention in which it is used by dissolving it in an organic solvent.

[Means to solve the problem]

The gist of the present invention is to add a carboxylic anhydride having an unsaturated double bond to a polyolefin, and then chlorinate it to obtain a modified chlorinated polyolefin, which is then reacted with a polyhydric alcohol. This invention relates to group-containing modified chlorinated polyolefins and coating compositions using the same.

The present inventor previously proposed in Japanese Patent Application No. 63-131430 a method of chlorinating and reducing an oxidized polyolefin obtained by thermally degrading a polyolefin with oxygen to contain a hydroxyl group. This is different from the one obtained by subjecting a polyhydric alcohol to an esterification reaction on a carboxylic acid anhydride adduct.

The polyolefin used in the present invention is polyolefin such as polyethylene, polypropylene, ethylene/propylene copolymer, ethylene vinyl acetate, etc. Because it is used as a coating material for paints, inks, etc., the degree of polymerization of the polymer is about 1000 to So, 000. Preferably. If it is higher than this, the viscosity of the resulting resin is high and it is inconvenient to paint and handle, and if it is lower than this, the coated surface will be too soft, which is not preferable.

As the acid anhydride having an unsaturated double bond used in the present invention, acid anhydrides such as maleic anhydride, itaconic anhydride, and citraconic anhydride are preferred. The reason is that when reacting with a polyhydric alcohol, a ring-opening reaction occurs first, and a single molecule reaction occurs selectively, but the esterification reaction occurs even if the ring is opened, so the unsaturated acids mentioned above can be used. .

Next, the chlorination method in the chlorination step is usually carried out using a chlorine-resistant solvent such as carbon tetrachloride.

Dissolve benzoyl peroxide, dicumyl peroxide under pressure or normal pressure using a solvent such as trichloroethylene or tetrachloroethane.

It is chlorinated with gaseous chlorine using a peroxide such as lauroyl peroxide or tcrt-butyl oxide or ultraviolet light as a catalyst. The content of chlorine is not particularly limited, but it should be 40 to 60%, considering the suitability for forming a paint.
is preferred. This is determined based on the solubility in organic solvents, the flexibility of the coating film, etc.

The polyhydric alcohols used in the present invention include ethylene glycol, propylene glycol, 1.4-butanediol, 1.5-bentanediol, 1.6hexanediol, cyclopentane-1,2-diol, and cyclohexane-1,2-diol. -diol, glycerin, propanediol,
Bisphenol A.

These include trimethylolpropane, pentaerythritol, etc., but in order to carry out the reaction quickly and efficiently, high boiling point alcohols that can undergo high temperature reactions are preferred.

Further, as organic solvents used for festering, solvents generally used in paints, varnishes, inks, etc., such as aromatic solvents such as xylene and toluene.

Dimethylbenzene and the like, ester solvents such as ethyl acetate and butyl acetate, and ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone are used.

Isocyanates used in the present invention include tolylene diisocyanate, hexamethylene diisocyanate,
Trimethylhexamethylene diisocyanate, 4.4'
- diphenylmethane diisocyanate and derivatives thereof such as coronae) HL (Japan Polyurethane Industries),
Desmodule (Bayer AG) etc. are used.

The CPO-OH resin of the present invention reacts with isocyanate compounds to form a cured coating film, so it can
It can improve the durability of undercoat, etc. This is a performance that cannot be expected from conventional chlorinated rubber paints.

〔Example〕

The present invention will be specifically explained below with reference to Examples.

Production example - ■ 1000g of low molecular weight polyethylene with an average molecular weight of 4500
was placed in a 21 separable flask and melted in an oil bath at 200°C. Add 40 g of maleic anhydride into it (stir and add a solution of 4 g of benzoyl peroxide dissolved in 100 ml of carbon tetrachloride over 30 minutes. After the addition is complete, carry out a 2-hour reaction to remove unreacted monomers. And in order to remove the volatile matter, the volatile matter was removed under a vacuum of 600 mm or more of mercury column.

The maleic anhydride-modified polyethylene obtained above was ground in a mortar and washed in acetone. It was dried and ground. After doing this three times, an R absorption spectrum was taken and From the presence of a maximum absorption wavelength near 1, it was confirmed that maleic anhydride was addition-polymerized to polyethylene.

Next, 1000 g of maleic anhydride-modified polyethylene was
It was completely dissolved in carbon tetrachloride of 2 atmospheres at a temperature of 100° C., and while irradiated with ultraviolet rays, gaseous chlorine was blown from the bottom to perform chlorination. Depending on the amount of chlorine blown, the reaction solution was sequentially extracted, and chlorinated products of maleic anhydride-modified polyethylene having different degrees of chlorination were collected.

Sampling was carried out at three points of 40.50.60% calculated from the amount of blown chlorine. Subsequently, as much carbon tetrachloride as possible was removed from these reaction solutions by distillation to obtain a high temperature and high viscosity solution, which was extruded at 100° C. using a vented extruder to solidify it.

Each of the chlorinated products obtained above is dissolved in toluene to prepare a 10% solution, which is dropped into a large amount of ethanol to precipitate the resin, which is then filtered and dried. Depending on the form, film molding or KBr tablets are prepared and an IR spectrum is taken. By chlorination, 3000~
Absorption at 2800 cm-1 (C-H) decreases 726-68
5 cm-11, Nibrod (C-Cj) was confirmed by increasing absorption.

The above-mentioned maleic anhydride-modified chlorinated polyethylene having a chlorine content of 40.50.60% is ground to approximately 3rJ mesh, and 18 g of 1,4-butanediol is added to 300 g of each mesh and mixed well.

This was placed in a 11 separable flask equipped with a stirrer and melted, followed by reaction at 200°C for 30 minutes.

At this time, no particular catalyst is used (although the ring-opening reaction can easily occur if the temperature is high enough).

The obtained hydroxylated maleic anhydride-modified chlorinated polyethylene (hereinafter referred to as CPE-OH) was
After dissolving in toluene to make a 10% solution, it was dropped into a large amount of ethanol to precipitate the resin, which was then filtered and dried. After repeating this process three times and completely drying under reduced pressure, an IR spectrum was taken, and broad absorption was observed from 36.00 to 3200 cm-1, confirming that 10H groups were introduced.

When the obtained CPE-OH was made into a 40% xylene solution and its solubility was checked, it was found that it became a homogeneous solution. In addition, when the viscosity at 25°C was measured,
CPE-OH with a degree of chlorination of 40% is 480 cpi, 50
% CPE-OH is 41Qcps.

60% CPE-OH was 380 cps.

This xylene solution was added to CPE-0H-1 and CPE, respectively.
-0H-2 and CPE-0H-3 and will be used for subsequent tests.

Production example - ■ 1000 g of isotactic polypropylene with an average molecular weight of 25.000 was placed in a separable flask 2.
The mixture was melted at 00°C with stirring. 30 g of maleic anhydride was added thereto, mixed well, and then 3 g of dicumyl peroxide diluted with 100 ml of carbon tetrachloride was added to 30 g of maleic anhydride.
Added within minutes. After the addition was completed, the reaction was continued for 2 hours. Carboxylation of the reactant was confirmed by infrared absorption spectrum in the same manner as in Production Example ①. Subsequently, 1000 g of maleic anhydride-modified polypropylene was dissolved in 101 carbon tetrachloride at 2 atmospheres and a temperature of 100° C., and chlorination was performed while irradiating with ultraviolet light. Chlorinated products with a chlorine injection amount of 45% and 55% were obtained. Carbon tetrachloride from the reaction solution was removed by concentration as much as possible, and this was extruded at 110° C. using an extruder with a head to obtain a solid product.

It was confirmed that this product was also chlorinated using the same method as in Production Example-①.

Next, maleic anhydride modified with a degree of chlorination of 45% and 55% was placed in a separable flask equipped with a stirrer and melted at 180°C, and 25g each of 1.6-hexanediol was added and stirred thoroughly. Allowed to react for minutes.

It was confirmed that the hydroxyl group was introduced using the same method as in Production Example-■.

The thus obtained hydroxylated maleic anhydride-modified chlorinated polypropylene (hereinafter referred to as CPP-OH) was dissolved in xylene to a concentration of 30%.
The viscosity at 25°C was measured using a viscometer. 45% chlorine 4
It was a homogeneous solution with 5Qcps and 55% of 360cps. The former is CPP-0H-1, the latter CPP-
It will be called 0H-2 and will be used for subsequent tests.

Example-I CPE-0H-1 and CPE-0H-2 obtained in Production Example-■
, CPE-0H-3 was used to make the top coat S with the following formulation.
Prepared by G mill.

1. Paint composition Zero book This example Comparative example CPE-0H-1, 2, 3 R-10 iQ2 Toyopara-150 Epicoat 828 Xylene 48.0 31.1 31.1 $8.5 ” 0.4 0.4 20 .5 41.3 Tot 1 100.0 100.Q Solid(%1 50.0
5B, 8 Plasticizer (chlorinated paraffin) This book Stabilizer (epoxy resin) Zero book Comparative example, chlorinated rubber (CR-10) Put the above compound in an SG mill, add 100 g of glass beads,
A paint was prepared by kneading for 1 hour.

2. Preparation method of test panel Add hardening agent (Coronet) to 100g of prepared paint.
-HL, Nippon Polyurethane Industry) 6.2 g was added and stirred in an SG mill for 10 minutes. No curing agent was added to the chlorinated rubber paint of the comparative composition.

A sandblasted board that had been previously coated with an inorganic zinc primer and dried was coated with the above paint twice, air-dried for 7 days, and then subjected to the following coating test.

3. Test method Test method (1) Adhesion of paint film Cross-cut test: Cut goblets at intervals of 2111111 on the paint film, apply Sellotape on top of it, and forcefully peel it off.

(2) Impact test mandrel Impact tester load 500 g, height 30an, 5[1cm evaluation ◎
No peeling or cracking O No peeling, cracking × Both peeling and cracking (3) Drawing test After drawing under a load of 500 g, peel off with cellophane tape.

◎ No peeling 0 Slight peeling × Peeling (4) Weather resistance test Sun 5hine weather meter shows 0°3
Appearance and gloss measurement after 00, 600, and 1000 hours (5) Impact test after weather resistance test (secondary physical properties) Performed according to (1), (2), and (3).

(6) Solvent resistance test 1 Observation and evaluation of toluene solvent resistance of the test panel after being left at room temperature for a month O Insoluble in toluene -1...Degree of chlorination 40%, 1.4
-Butanediol treatment example CPE-0B-2...Degree of chlorination 50%, 1.4
-Butanediol treatment example CPE-0H-3...Degree of chlorination 60%, 1.4
- Comparative example of butanediol treatment... Chlorinated rubber (CR
-10) Example-■ CPP-0H-1 and CPP-0H-2 obtained in Production Example-■
A top coat was prepared using the following recipe using an SG mill.

■, Paint composition example Comparative example CPP-0H-1,262,rJ Chlorinated polypropylene - 18,7TiQ2
31.1 31.1 TOYOPARA-1
50" -8,5 Epicoat 828" Q,4 0.4
Xylene 6.5 41.3Tot
sl 100.0 100.03o
lid (%) 50.0 58.8
Plasticizer (chlorinated paraffin) Stabilizer (epoxy resin) Comparative example, chlorinated polypropylene (Superclone 1θ6-H) The above mixture was placed in an SG mill, 100g of glass peas was added, and the mixture was heated for 1 hour. A mixed paint was prepared.

2. The test panel preparation method is the same as above 3. The test method is the same as above 4. Test results Type of paint resin and paint Nα Example CPP-0H-1... Chlorination degree 45%, 1.6
-Hexanediol treatment example CPP-0H-2...Chlorination degree 55%, 1.6
- Comparative example of hexanediol treatment Chlorinated polypropylene (Super Chron 106H) [Effects of the invention] From the above results, the conventional chlorinated rubber paint (comparative example) Although it lacks long-term durability because it cannot be used as a paint without the agent, it is clear that it not only has very good primary and secondary physical properties, but also has improved solvent resistance.

Procedural amendment (voluntary) Contents of the amendment 2, Title of the invention: Hydroxyl group-containing modified chlorinated polyolefin composition and its production method 3, Relationship with the case of the person making the amendment Patent applicant address: 4 Marunouchi-chome, Chiyoda-ku, Tokyo 5th name
Name (234) Sanyo Kokusaku Pulp Co., Ltd. 4, Agent Address: 16, Kanda Kita Jomono-cho, Chiyoda-ku, Tokyo, 101 Ei Building, 3rd Floor, 5, Claims column of the specification to be amended and detailed description of the invention Column 1 and Scope of Claims are corrected as shown in the attached sheet.

2. Correct the following items in the detailed description of the invention column.

(+1 From the last line of page 4 of the specification to the first line of page 5, the term ``acrylic acid monomer'' has been corrected to ``acrylic acid containing a hydroxyl group.'' (2) In the 8th line of page 5 of the specification box, ``Maintenance (3) On page 6, lines 15 and 16 of the specification, the phrase "was too soft," was replaced with "for maintenance purposes." (4) In the 4th line of page 10 of the specification, the statement ``by addition polymerization to polyethylene'' is corrected to ``by addition to polyethylene.'' (5) In the 1st line of page 13 of the specification. "carboxylation" should be replaced with "carboxyl group"
(6) On page 16, lines 19-20 of the specification, the statement "(5) Impact test (secondary physical properties) after weather resistance test" has been changed to [(5)
) Secondary physical properties (weather resistance test: Tested after 100 OHrs) (Separate paper) Claims (1) After adding a carboxylic acid anhydride having an unsaturated double bond to a polyolefin, this is chlorinated and further A coating composition using a novel hydroxyl group-containing modified chlorinated polyolefin obtained by reacting a hydrolic alcohol.

(2) The coating composition according to claim (2), wherein at least an equimolar amount of isocyanate and/or polyisocyanate is added to the equivalent amount of hydroxyl groups.

(3) Hydroxyl group-containing modified chlorination, which is characterized by adding a carboxylic anhydride having an unsaturated double bond to a polyolefin and then chlorinating it to obtain a modified chlorinated polyolefin, which is then reacted with a polyhydric alcohol. Polyolefin manufacturing method.

Claims (3)

[Claims] (1) A coating composition using a novel hydroxyl group-containing modified chlorinated polyolefin obtained by adding a carboxylic anhydride having an unsaturated double bond to a polyolefin, chlorinating it, and then reacting it with a polyhydric alcohol. . (2) The coating composition according to claim 2, further comprising an isocyanate and/or polyisocyanate added thereto at least in proportion to the equivalent amount of hydroxyl groups. (3) Hydroxyl group-containing modified chlorination, which is characterized by adding a carboxylic anhydride having an unsaturated double bond to a polyolefin and then chlorinating it to obtain a modified chlorinated polyolefin, which is then reacted with a polyhydric alcohol. Polyolefin manufacturing method.