JPS59230020A - Production of curable resin - Google Patents

Abstract

PURPOSE:To obtain the titled novel resin having various excellent physical properties and containing unsaturated bond in side chain, without restriction in molecular weight, by reacting a polymer containing hydroxyl group in side chain with a specific unsaturated isocyanate by a specific method. CONSTITUTION:(A) an unsaturated isocyanate containing free NCO group and (meth)acryloyl group and obtained by the addition reaction of (i) a polyvalent isocyanate with (ii) an unsaturated monoalcohol containing (meth)acryloyl group is added to (B) an organic solvent solution of a polymer containing hydroxyl group in side chain to effect the reaction of the NCO group of the component A and the hydroxyl group of the component B and obtain an unsaturated polymer containing (meth)acryloyl group in the side chain. The obtained polymer is added with (C) a polymerizable monomer having a boiling point higher than that of the organic solvent used in the above reaction by >=10 deg.C, and the organic solvent is distilled off selectively under normal or reduced pressure taking advantage of the boiling point difference. The objective resin is produced in the form of a solution in the component C.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a curable resin, and more particularly, to a method for producing a novel radical-curable resin having a polymerizable unsaturated bond in a side chain.

The types of radical-curable resins have also increased, from the first unsaturated polyester resins, to diallyl phthalate resins, and in recent years to resins with acryloyl or methacryloyl groups.
So-called unsaturated acrylate type resins (also called oligoacrylates) are being used extensively due to their unique features.

In particular, vinyl ester resins (epoxy-acrylates) have made remarkable advances in the corrosion-resistant field.

However, as applications expand, there are many cases in which new physical properties are required.

Radical hardening wall resins are no exception, and are required to have +9 water resistance and chemical resistance, as well as coatings with advanced physical properties such as high hardness and adhesion, and molded resins with excellent weather resistance. This is just one example.

Each conventional type of resin has its own characteristics and is used for that reason, but there are times when it is not possible to satisfy the required performance within the framework of the conventional type of resin.

Whether it is polyester resin or oligoacrylate, the molecular weight of the resin before curing is as high as 3000, and there are bonds in the main chain of the constituent molecules that can be hydrolyzed, such as ester bonds. 1 because it contains
Under severe conditions such as circulating hot water of oo0, the performance will fall short of the required practical durability, especially when the resin is not alone, such as FRP combined with glass fiber.

The present inventors have proposed 1. As a result of repeated research into a resin that exhibits performance that cannot be met with conventional resins, we found that the polymer that makes up the main chain of radical-curing resins does not contain any specific bonds that are easily decomposed, and its molecular weight is extremely high. It was assumed that this would be desirable.

However, for unsaturated polyesters that have unsaturated bonds in the main chain polymer, the risk of gelation increases rapidly as the molecular weight increases during esterification. It is extremely difficult to raise the temperature to about 100,000 yen or higher.

The presence of many ester bonds in the polymer also suggests that there is a limit to its hydrolysis resistance.

In fact, it is known that variations in the concentration of ester bonds per unit volume govern the chemical resistance and water resistance of the resin.

Furthermore, it is typified by vinyl ester resin. For oligoacrylates, that is, when they have a crosslinking point such as a 7-acryloyl group or a methacryloyl group at the end of the molecule, an increase in the molecular weight beyond the limit of the oligoacrylate will inevitably lead to a decrease in the crosslinking point, and the curability will decrease. There is a significant tendency for physical properties such as delay and heat resistance to deteriorate.

In addition, the difficulty of synthesis due to the increase in viscosity is added, and even in this case, it is not possible to increase the molecular weight, and the upper limit is F) 3000.

As one method for improving the above-mentioned drawbacks, attempts have been made for some time to synthesize polymers having unsaturated bonds in their side chains.

flJ, t) A solution of a polymer containing carboxyl groups in an organic solvent may be reacted with an unsaturated epoxy compound such as glycidyl methacrylate, or conversely, a polymer containing epoxy groups may be reacted with acrylic acid.

Regardless of whether it is used in solution form, in order to obtain an ioo% reactive radical-curing resin that does not contain volatile components, the solvent must be removed and the polymerizable monomers (hereinafter abbreviated as monomers) must be prepared as a solution. There must be.

For this reason, if a non-solvent is added to a solution of a polymer having unsaturated bonds in its side chain to precipitate the polymer and then drying is attempted, gelation occurs during the process and the objective cannot be achieved.

The present inventors have created a resin with pendant 7-kryloyl groups or methacryloyl groups on the side chains of a polymer, which has no molecular weight restrictions, can be cured by conventional curing methods, and can overcome problems in physical properties. Deaf unsaturated polymer,
As a result of repeated studies on methods for stable production, it was discovered that the object could be achieved by the following method, and the present invention was completed.

That is, the present invention involves adding a polyvalent isocyanate and an unsaturated polymer having an acryloyl group or a methacryloyl group to a solution of a thermoplastic polymer having a hydroxyl group in the side chain in an organic solvent.
Acryloyl groups are added to monobolymer side chains by adding an unsaturated isocyanate having a free Q isocyanate group and reacting the hydroxyl groups of the polymer side chain with the isocyanate groups of the unsaturated isocyanate. After synthesizing an unsaturated polymer having a methacryloyl group or a methacryloyl group, a polymerizable monomer (hereinafter abbreviated as monomer) having a boiling point higher than the boiling point of the organic solvent used in the production above (hereinafter referred to as monomer) is added at any stage. In addition, by selectively distilling off the organic solvent by utilizing the boiling point difference under normal pressure or reduced pressure, it is possible to safely synthesize a heptamer solution of an unsaturated polymer without the risk of gelation. This is true.

In order to obtain a solution of a polymer in an organic solvent, it is most convenient to synthesize the polymer by solution polymerization and is sufficient for the purpose of the present invention. A solid polymer may be dissolved.

Since incyanate is used in the reaction, the organic solvent must not contain hydroxyl groups, carboxyl groups, amino groups, etc. that react with incyanate groups, and it is also undesirable for water to be mixed into the organic solvent.

Furthermore, it is desirable that the boiling point be as low as possible, and the solubility of the polymer must also be high. From this point of view, suitable solvents for the present invention include, for example, the following types: (a) Aromatic hydrocarbon type: benzene, toluene, xylene: (o) x Sulf' /I/ type : Methyl acetate, ethyl acetate, propyl acetate, butyl acetate; (iii) Ketones: methyl ether ketone, methyl isobutyl ketone; , chloroform, trichloroethylene, ethylene dichloride, / , /, , /-trichloroethane.

These are selected depending on the type of polymer.

As the monomer (1) for producing the polymer containing hydroxyl groups constituting the polymer component (A) of the resin of the present invention, currently commercially available monomers are available, and examples include the following types: methylene, Vinyltoluene, chlorostyrene, acrylates (methyl, ethyl, butyl, two-ethylhexyl, etc.), methacrylates (methyl, ethyl, butyl, -monoethylhexyl, lauryl, benzyl, cyclohexyl, tetrahydrofurfuryl) etc.), acrylonitrile, vinyl acetate, vinyl propionate, vinyl versatenate, ethylene, ztadiene, vinyl chloride.

Examples of the monomer (2) for introducing the bohydroxy ρ group of the component [Δ] include hydroxyethyl acrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxyethyl acrylate, and methylolacrylamide. In the case of vinyl acetate copolymers, it is also useful to saponify them to form vinyl alcohol residues.

Furthermore, examples of polyvalent incyanate groups in the component of the present invention include diisocyanate, naphthylene diisocyanate, hexamethylene diisocyanate, inphorone dimesocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, etc. is common and sufficient for the purposes of the present invention.

Examples of the unsaturated monoalcohol which reacts with polyvalent incyanate to introduce an acryloyl group or methacryloyl group unsaturated bond include those of the type of monomer (2) described above.

The reaction between the hydroxyl group in the polymer (A) molecule and the unsaturated isocyanate can be carried out without a catalyst or with a polymerization inhibitor such as polyhydric phenols, or with a tertiary amine, an organic tin compound, etc. It is convenient to carry out the reaction in the presence of a commonly used urethanization catalyst.

Further, it is necessary to carry out this reaction in the presence of air (oxygen) in order to prevent polymerization of the acryloyl group or methacryloyl group.

Next, examples will be shown below to help understand the present invention.

To Examples (a) Synthesis of a polymer having a hydroxyl group in the side chain (AJ) Into a 7-parameter flask equipped with a stirrer, a temperature needle, a mechanical funnel, and a reflux condenser 79-1, benzene co!09,
Azobisisobutyronitrile/9; IF uryl mercaptan O,-g was charged, and the mixture was replaced with nitrogen gas, and a mixed monomer of 1-g of sterene and 3 tg of -monohydroxyglobil methacrylate was added dropwise under the boiling point of benzene.

After completion of the reaction, refluxing is repeated for 72 hours below the boiling point of benzene.

After the reaction was completed, 0.71 g of hydroquinone was added to prepare a benzene solution (A) of a copolymer of sterene-hydroxyglobyl acrylate having a hydroxyl group in the side chain.
The boiling point goc of benzene is obtained.

(B) Unsaturated isocyanate (B) 17) Synthesis - Attach a thermometer, a stirrer, a reflux condenser, and a complete
In a ctl separable flask, add 0.3 g of dirt lylene diisocyanate, 0.0 g of benzene, 0.3 g of dibutyltin dilaurate, and 0.3 g of hydroquinone. Ifi,
A homogeneous solution of copper naphthenate (1% Ou) / 01)1)In is heated to 40" (J) and then 300 g of co-hydroxypropyl methacrylate is added dropwise. Cooling is rather necessary during the dropwise addition. Become.

When stirring was continued for 3 hours at the same temperature after the completion of the application, as a result of infrared analysis, the free hydroxyl group of Decola disappeared.

A pale yellow-green benzene solution of unsaturated incyanate (B) was obtained.

(c) Synthesis of side chain double bond resin (I) In a 3-liter flask equipped with a thermometer, a stirrer, and a reflux condenser,
Polymer (A) (benzene solution vt > zoog, unsaturated incyanate) (B) (benzene solution) / 10g was charged and stirred at 60-70°C for 4 hours in an air stream. As a result of infrared analysis, free incyanate was found. It was observed that the base had completely disappeared.

Next, change the reflux condenser to a fractional distillation condenser, distill off about ihog of benzene until the contents become slushy, then add sterenkooog (boiling point of styrene/4
Ij℃) Approximately 200g under reduced pressure, content temperature tacho℃~
'Only benzene is selectively distilled off at Ij°C.

After benzene was distilled off, styrene ioog was added to make a homogeneous solution, and the side chain double bond resin (1) was pale yellow and had a viscosity of /6.
．． Obtained as a lI bois liquid.

'flB Fat (I) / Oo part contains 3 parts of methyl ether ketone peroxide, cobalt naphthenate (6% CO)
When 1 part is added, it gels at room temperature in about 1 hour, slowly emits heat, and then hardens.

A tough cured resin with a surface hardness of dH after 7 days is obtained.

Example.

B) Preparation of polymer (0) having hydroxyl groups in the side chain Into a separable flask equipped with a stirrer, thermometer, reflux condenser, and dropping funnel, add ethyl acetate yoog,
Bency peroxide/I/3. lit.

Lauryl Mercagtan 0. /! ; 79 was charged, and under reflux of ethyl acetate in a nitrogen stream, 3 cores of butyl acrylate
, acrylonitri/I/lSg, --hydroxyethyl acrylate/lio mixed monomers are added dropwise.

After completion of the application, heat for 16 hours and reflux the ethyl acetate.

After the reaction was completed, 0.3 g of hydroquinone was added to obtain a polymer having hydroxyl groups in the side chain (an ethyl acetate solution of (3) was obtained in the form of a pale yellow liquid.

(e) Unsaturated incyanate (DJ synthesis) In a /l separable flask equipped with a thermometer, a stirrer, a reflux condenser, and a dropping funnel, put l,6-hexamethylene diisocyanate/419, triethylenediamine 063g, and acetic acid. 20 g of ether, 0./9 of phenothiazine are charged, the temperature is raised to 60° C. and then 11-hydroxyethyl acrylate//6 fi is slowly added dropwise.

As a result of infrared analysis, when it appeared that the free hydroxyl groups had undergone a taco-reaction, no further decrease in hydroxyl groups was observed, so the reaction was stopped. The unsaturated isocyanate (DJ) is obtained as a light yellowish brown color.

(to) Production of side chain unsaturated bond polymer 1)) In a 3-liter flask equipped with a stirrer, a thermometer, and a reflux condenser, add 9ff-(0) (ethyl acetate solution') ttog and unsaturated isocyaner) ( D) (Ethyl acetate solution>
6oy was added and the mixture was heated to 7θ in an air stream to t”O (the boiling point of ethyl acetate is 77°C) for 6 hours, and as a result of infrared analysis, free incyanato groups completely disappeared.

Next, change the condenser to a fractional distillation type and distill out about 200 cc of ethyl acetate, then add 200 g of 6-hexanediol diacrylate and trimethylolpropane triacrylate. ? The remaining ethyl acetate is distilled off and separated under reduced pressure using 0011XH.

The obtained side chain polymerizable resin [1] is a pale yellow liquid with a viscosity of about 1 da O void.

After adding ioo part of the side chain double bond polymer [expletive], -1 ethylhexyl acrylate lo9, and part of Tepa's Irgacure #bstt- as the light layer 1a agent to make a uniform solution, JOOWIl, XJOOWg plain eye poly- It was packaged in a polyvinyl chloride mail box with a bar coater to a thickness of 0.7 nm, and was exposed to an ultraviolet irradiation machine with an output of 10 kW.
m was passed at a speed of tom1 minute.

The cured film is glossy and strong with a lead hardness of F, so it can easily follow the deformation of the PVC tile, and it also showed good properties in the cross-cut adhesion test.

Example 3゜(g) Polymer (manufactured by Nephew) A polymer consisting of approximately 91% vinyl chloride (by weight, the same hereinafter), approximately y% vinyl acetate, and approximately 6% polyvinyl alcohol (Sure/A manufactured by Okisui Kagaku Co., Ltd.) was dissolved in 200 parts of tetrahydrophene (boiling point wolfberry) and 200 parts of tetrahydrophene (boiling point wolfberry) to prepare a polymer (gradient) having a hydroxyl group in the side chain.
A tetrahydrophene solution) was prepared.

Example Synthesis of unsaturated isocyanate (F) In a four-eye flask equipped with a stirrer, a thermometer, a reflux condenser, and a funnel, 2 pieces of isophorone diisocyanate, 29 g, benzene, 130 g, and diptene dilaurate θ''' 9
.

λ,! -Diphenylhydroquinone o, osIf preparation,
While raising the temperature to 60°C, 74Mg of co-hydroxyglobil methacrylate (co-hydroxyglobil methacrylate) was completely applied. 3 at 60℃ after full application
When kept for a certain period of time, most of the hydroxyl groups disappear, and unsaturated incyanate (F) is obtained in the form of a pale yellow liquid.

Side chain double bond polymer [Button manufacturing polymer (E) (tetrahydrofuran solution) sooy
was charged into a TL Mitsuro flask equipped with a stirrer, reflux condenser, and thermometer, and then unsaturated isocyaner) (
F) (Prepare benzene solution (capital) lJO9 60-70
As a result of infrared analysis of the cell which was reacted for S hours at .degree. C., it was found that the free isocyanate groups had virtually disappeared, and the reaction was considered to have been completed.

First, about 300 cc of a mixture of tetrahydrofuran and benzene was transferred under normal pressure, and then ethylene glycol dimethacrylate/609, chlorostyrene/Jr Oll
The tetrahydrofuran was removed under a reduced pressure of 600° H9 to obtain a side chain double bond polymer (II) in the form of a yellowish brown liquid with a viscosity of about /Iθ.

Side chain double bond polymer [Ioo part, 5 parts of antimony trioxide, Bency peroxide/I/(g.

%DOP paste) and 0.1 part of dimethyl Ayurif were poured into a polyethylene beaker and allowed to harden. After about 1 hour, it turned into a gel and cured while gently generating heat.

The surface hardness of the cast product after being left overnight was 3H, and even if it was ignited by exposing it to the flame of a gas burner, it self-extinguished as soon as the burner was removed.

Claims (1)

[Claims] (IXA) In a solution of a polymer containing a hydroxyl group in its side chain in an organic solvent, an adduct of a polyvalent isocyanate and an unsaturated monoalcohol having an acryloyl group or a methacryloyl group, free Add an unsaturated isocyanate having an incyanato group and a 7-acryloyl group or a methacryloyl group, and react the hydroxyl group of [A] with the iso-7 anato group of [A] to form a polymer having an acryloyl group or a methacryloyl group in the side chain. After synthesizing the unsaturated polymer, (1) the boiling point of the organic solvent used in (I) is 10
Add a polymerizable monomer (monomer) with a high boiling point above ℃,
1. A method for producing a curable resin, which comprises forming a monomer solution of a cine-saturated polymer by selectively trap-distilling an organic solvent under normal pressure or reduced pressure using the difference in boiling points.