JPH04332711A - Hydrophilic resin - Google Patents

Abstract

PURPOSE:To obtain a resin suitable for contact lens material, etc., having hydrophilic nature, excellent transparency, heat resistance, mechanical strength, etc., maintaining high elasticity even at high temperature by polymerizing a specific diester monomer. CONSTITUTION:A monomer comprising a diester monomer [preferably fumaric acid type monomer such as di(2-hydroxyethyl) fumarate] shown by the formula (n is 1-10) to give the objective resin. The polymerization is preferably carried out by using a radical polymerization agent such as benzoyl peroxide in an atmosphere of an inert gas such as nitrogen at 30-100 deg.C for 5-72 hours. In case another copolymerizable monomer is used besides the monomer shown by the formula, 5-1,000 pts.wt. copolymerizable monomer such as styrene based on 100 pts.wt. monomer shown by the formula.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydrophilic resin having excellent hydrophilicity, transparency, and heat resistance.

0002

[Prior Art] Hydrophilic resins are resins that have hydrophilic groups such as hydroxyl groups, carboxylic acid groups, carboxylic acid salts, and amide groups in their molecules and are water-soluble or water-swollen. It is used in various fields such as cosmetics, adhesives, sanitary materials, and medical. As the hydrophilic resin,
For example, polyvinyl pyrrolidone, methyl vinyl ether-maleic anhydride copolymer, polyacrylamide, polyvinyl alcohol, polyethylene glycol, poly-
2-hydroxyethyl methacrylate.

0003

[Problems to be Solved by the Invention] However, the polymerization rate of polyvinylpyrrolidone, methyl vinyl ether-maleic anhydride copolymer, and polyacrylamide is extremely high, making it difficult to control the polymerization reaction and making it impossible to adjust the molecular weight. There's a problem. In addition, the produced polymers are unstable and have significant coloration, and furthermore, they are brittle when used as films or molding materials.

[0004] Furthermore, the polyvinyl alcohol, poly-
2-Hydroxyethyl methacrylate and polyethylene glycol can be used as films and molding materials, but their low heat resistance limits their use at high temperatures, and their tensile strength, tear strength, etc. There is a problem that the strength of polyvinyl alcohol and polyethylene glycol is low, and furthermore, polyvinyl alcohol and polyethylene glycol have a problem that transparency cannot be obtained in a water-free state.

[0005] Accordingly, an object of the present invention is to provide a hydrophilic resin that is hydrophilic and also has excellent transparency, heat resistance, mechanical strength, etc.

[0006]

[Means for Solving the Problems] According to the present invention, a diester monomer (hereinafter referred to as diester monomer 1) represented by the following general formula 2 (wherein n represents an integer from 1 to 10) is contained. A hydrophilic resin obtained by polymerizing raw material monomers is provided.

[0007]

[Case 2]

The present invention will be explained in more detail below.

In the hydrophilic resin of the present invention, the diester monomer used as an essential component is the diester monomer 1 represented by the general formula 2 above. In the diester monomer 1, if n exceeds 10, the polymerizability of the monomer, the transparency of the resulting polymer, and further the mechanical strength will decrease, so it cannot be used.

As the diester monomer 1 represented by the general formula 2, specifically, for example, di(2-hydroxyethyl) fumarate, di(diethylene glycol)
Fumarate, di(triethylene glycol) fumarate, di(tetraethylene glycol) fumarate, di(nonaethylene glycol) fumarate, di(2-hydroxyethyl) malate, di(diethylene glycol) malate, di(triethylene glycol) malate, di Preferred examples include (tetraethylene glycol) malate, di(nonaethylene glycol) malate, etc.
Among them, fumaric acid type monomers can be preferably used because they have particularly good polymerizability and can impart high hydrophilicity, heat resistance, and strength to the resulting polymer.

The diester monomer 1 can be prepared, for example, by reacting fumaric acid (maleic acid) dichloride with a specified glycol in the presence of an amine, or by reacting fumaric acid (maleic acid) with a specified glycol. It can be easily obtained by a method of reaction in the presence of an acid catalyst such as sulfuric acid or para-toluenesulfonic acid. The obtained product can be purified by known methods such as distillation and recrystallization.

In the present invention, other than the diester monomer 1, monomers copolymerizable with the diester monomer 1 that can be used as raw material monomers include, for example, styrene, α-methylstyrene, methylstyrene, chloro Styrene, vinyl acetate, vinyl propionate, vinyl pivalate, methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, (meth)acrylic acid, (meth)acrylic amide, 2-hydroxyethyl (meth)acrylate, ) Acrylate, ethyl vinyl ether, n-butyl vinyl ether, N-vinylpyrrolidone, vinyl chloride, vinylidene chloride, ethylene, propylene, isobutylene, acrylonitrile, etc. can be preferably mentioned, and they can be used alone or as a mixture. At this time, the amount of the monomer used is 1
It is preferable to use it in a range of 1000 to 5 parts by weight per 100 parts by weight. If it exceeds 1000 parts by weight, the properties such as hydrophilicity and heat resistance of the diester monomer 1 will deteriorate, and if it is less than 5 parts by weight, the effects of copolymerization cannot be exhibited, which is not preferable.

The copolymerizable monomers include, for example, allyl (meth)acrylate, di(meth)acrylate, diallyl phthalate, divinylbenzene,
Polyfunctional monomers such as methylenebisacrylamide can also be used. In this case, the amount of the polyfunctional monomer used is preferably in the range of 20 parts by weight or less per 100 parts by weight of the diester monomer 1, and the resin obtained in this case can be a resin made of a crosslinked polymer. .

[0014] To prepare the hydrophilic resin of the present invention, radical polymerization or copolymerization may be carried out by known polymerization methods such as bulk polymerization, suspension polymerization, emulsion polymerization, and solution polymerization in the presence of a radical polymerization initiator. can be easily obtained. Examples of the radical polymerization initiator include benzoyl peroxide, lauroyl peroxide, diisopropyl peroxydicarbonate, t-butylperoxy-2-ethylhexanoate, t-butylperoxypivalate, t-butylperoxydiisobutyrate, azobis isobutyronitrile,
Azobisdimethylvaleronitrile, persulfates, persulfate-bisulfite systems, and the like can be preferably used. The amount of the polymerization initiator used is preferably 0.01 to 10 parts by weight, more preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the monomer.

[0015] To carry out the polymerization or copolymerization, nitrogen,
It is preferable to substitute the polymerization system with an inert gas such as carbon dioxide or helium or to carry out the reaction under an atmosphere. Further, the polymerization temperature is preferably in the range of 30 to 100°C, and the polymerization time is preferably in the range of 5 to 72 hours. In addition, the average molecular weight of the hydrophilic resin obtained at this time is not particularly limited, but is preferably in the range of 5,000 to 300,000, and a high molecular weight resin can also be obtained by further performing operations such as fractionation. .

[0016]

Effects of the Invention The hydrophilic resin of the present invention is obtained by polymerizing raw material monomers containing diester monomers with a specific structure, so it has excellent hydrophilicity, transparency, and heat resistance, and can be used even at high temperatures of 100°C or higher. Can maintain high elasticity,
Furthermore, hydrophilicity can also be adjusted by changing the type of ester group. Therefore, hydrophilic resins can be used in coating materials, contact lens materials, intraocular lenses, cosmetics, biocompatible materials, sanitary materials, medical fields, etc.
It can be used in many fields. In addition to the above-mentioned uses, it can also be used as a material for improving the adhesion, dyeing, and antifogging properties of polymers, and can also be mixed with other monomers or polymers having isocyanate groups, carboxylic acid groups, glycidyl groups, etc. It can also be used as a crosslinked polymer.

[0017]

EXAMPLES The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited thereto.

[0018]

[Synthesis example] 1 mol of fumaric acid or maleic acid is added to the reactor.
, 3 mol of glycols shown in Table 1, 2 g of para-toluenesulfonic acid as a catalyst, and 200 ml of toluene as a solvent.
1 was charged, and an esterification reaction was carried out at 110 to 120°C for 8 hours under a nitrogen stream. After the reaction was completed, 500 ml of ethyl acetate and 200 ml of water were added to neutralize and wash with water, and toluene and ethyl acetate were distilled off from the obtained oil layer. The obtained crude products were purified by distillation to obtain the desired diester monomers. Table 1 shows the diester monomers obtained.

[0019]

[Table 1]

[0020]

[Example 1] Di(2-hydroxyethyl) fumarate 1
0 g, 10 cc of benzene containing 20 mmol/l of azobisisobutyronitrile as a radical polymerization initiator
were added and mixed, and solution polymerization was performed at 60° C. for 20 hours using a sealed tube method. After the polymerization was completed, the resulting polymer solution was poured into hexane, and the precipitated polymer was filtered, washed, and dried to determine the polymerization rate. The obtained polymer was 1H-NM
As a result of analysis by R, it was confirmed in the monomer -
The absorption of CH=CH- (6.7 ppm) has disappeared,
It was confirmed that the double bond of 2-di(hydroxyethyl) fumarate was cleaved. The analysis results are shown in Table 2. Further, the molecular weight was measured by GPC measurement, and other physical properties were measured using a transparent cast film of the polymer. The measurement method is shown below.

(A) Heat resistant dynamic viscoelasticity - Dynamic elastic modulus E'' (GPa) at 120°C was measured by temperature measurement. (B) Water content (W1-W2)/W1×100 W1: Saturated water content weight of time
W2: Initial weight of film (C)
Tensile Strength The film at saturated water content was tested at a tensile speed of 10 mm/min. The results are shown in Table 2.

[0022]

Examples 2 to 10 Polymerization was carried out in the same manner as in Example 1, except that the raw material monomers shown in Table 2 were used, and the physical properties of the resulting resins were measured. Also, regarding the obtained polymer, 1H
-NMR measurements showed that aromatic ring absorption was 6.75 to 7.22 ppm in the copolymer with styrene, and 2 ppm in the copolymer with vinyl acetate.
Absorption of -OCOCH3 was observed. The results are shown in Table 2.

[0023]

[Comparative Examples 1 to 3] Polymerization was carried out in the same manner as in Example 1, except that the raw material monomers shown in Table 2 were used, and the physical properties of the resulting resins were measured. The results are shown in Table 2.

[0024]

[Table 2]

Claims (1)

[Claims] Claim 1: The following general formula 1 (in the formula, n is 1 to 10
A hydrophilic resin obtained by polymerizing a raw material monomer containing a diester monomer represented by the following integer. [Chemical formula 1]