JPH0562892B2 - - Google Patents

Description

[Detailed description of the invention]

<Industrial Application Field> The present invention relates to a method for producing a thermosetting resin, and more specifically, to a method for producing a thermosetting resin, which has excellent heat resistance, hydrolysis resistance, chemical resistance, flame retardance, mechanical properties, etc., and low water absorption. The present invention relates to a method for producing a thermosetting resin with fast curing properties and excellent moldability. <Prior Art> In recent years, with the advancement of technology, resins with excellent heat resistance, mechanical properties, and moldability have been required. Among these resins, reaction-molding resins using reactive monomers or oligomers, that is, resins in which molding and polymerization are simultaneously performed using raw materials with relatively low viscosity, have attracted particular attention. Known examples of such resins include polyurethane resins, polyurea resins, nylon resins, epoxy resins, and unsaturated polyester resins, some of which are commercially available. However, each of these resins has its advantages and disadvantages; for example, polyurethane resins have low heat resistance, and unsaturated polyester resins have drawbacks such as the time required for reaction, that is, molding, and they do not necessarily have sufficient performance and moldability. I can't say that it is. Furthermore, the reaction between oxazoline and carboxylic acid is well known, and a thermosetting resin utilizing the reaction has also been proposed (Japanese Patent Application Laid-open No. 226021/1983). This thermosetting resin certainly has excellent mechanical properties, chemical resistance, etc., but its water absorption is extremely high, and its uses are severely limited. Furthermore, the reaction between oxazoline and phenols is known, and a resin using a bisphenolsulfone compound as the phenol has been proposed (Japanese Patent Application Laid-open No. 90219/1983). However, when tetrabromobisphenol S is used, for example, a resin with excellent mechanical properties and chemical resistance can be obtained, but the phenol component has poor thermal stability and is prone to coloration, decomposition, etc. during the curing reaction, which is a problem. It was hot. <Purpose of the Invention> As a result of intensive research to develop a new thermosetting resin, the present inventors found that the reaction between oxazoline and specific halogenated bisphenols is more specific than the reaction between oxazoline and bisphenols. The process proceeds extremely quickly in the presence of a catalyst, and the resulting thermosetting resin has excellent thermal stability, toughness, excellent hydrolysis resistance, and low water absorption. Furthermore, since no solvent is required, it has been found that reaction molding, for example, a two-liquid mixture type reaction molding, can be extremely usefully produced, and the present invention has been achieved. <Structure of the invention> That is, the present invention provides the following formula () [In the formula, n represents an integer of 2 to 4, and R represents an n-valent aliphatic, alicyclic, or aromatic hydrocarbon group. However, when n=2, R may be a direct bond. Ra,
Rb, Rc, and Rd each represent a hydrogen atom, an aliphatic hydrocarbon group having 3 or less carbon atoms, and an aromatic hydrocarbon group having 7 or less carbon atoms, and these may be the same or different. ] An oxazoline derivative represented by the formula () and a halogenated bisphenol represented by the following formula () are combined. [In the formula, This is a method for producing a thermosetting resin, which is characterized by carrying out a heating reaction in the presence of a catalyst. The oxazoline derivative used in the present invention has the following formula () This is a compound represented by In the above formula, n is 2 to 4
is an integer, of which 2 is preferred. R represents an n-valent aliphatic, alicyclic, or aromatic hydrocarbon group, and when n=2, R may be a direct bond. Specifically, when n=2, R is ethylene, trimethylene, propylene, tetramethylene, hexamethylene, neopentylene,
Examples include p-phenylene, m-phenylene, cyclohexylene, etc., and when n = 3

【formula】

【formula】

[Formula] etc. can be exemplified, When n=4

【formula】

[Formula] etc. can be exemplified. Among these, R is preferably an aliphatic group having 10 or less carbon atoms, an alicyclic group having 10 or less carbon atoms, or an aromatic hydrocarbon group having 12 or less carbon atoms. Ra, Rb, Rc and Rd each represent a hydrogen atom, an aliphatic group having 3 or less carbon atoms, and an aromatic hydrocarbon group having 7 or less carbon atoms, and these may be the same or different. Specific examples of aliphatic hydrocarbon groups having 3 or less carbon atoms include methyl groups and ethyl groups, and examples of aromatic hydrocarbon groups having 7 or less carbon atoms.
Examples include phenyl group and tolyl group. Ra,
It is preferable that all of Rb, Rc and Rd are hydrogen atoms, or any one of them is a methyl group and the rest are hydrogen atoms, and it is particularly preferable that all of them are hydrogen atoms. The oxazoline derivatives used in the present invention include:
Specifically, 2,2′-bis(2-oxazoline),
2,2'-ethylenebis(2-oxazoline), 2,
2'-tetramethylenebis(2-oxazoline),
2,2'-hexamethylenebis(2-oxazoline),2,2'-octamethylenebis(2-oxazoline),2,2'-1,4-cyclohexylenebis(2-oxazoline),2,2' -bis(4-methyl-2-oxazoline), 2,2'-bis(5-
methyl-2-oxazoline), 2,2'-m-phenylenebis(2-oxazoline), 2,2'-p-
Phenylene bis(2-oxazoline), 2,2'-
m-phenylenebis(4-methyl-2-oxazoline), 2,2'-m-phenylenebis(5-methyl-2-oxazoline), 2,2'-p-phenylenebis(4-methyl-2-oxazoline), 2 ，
Examples include 2'-p-phenylenebis(5-methyl-2-oxazoline) and 1,3,5-tris(2-oxazolinyl-2)benzene. Among these, 2,2'-bis(2-oxazoline), 2,2'-tetramethylenebis(2-oxazoline), 2,2'-m-phenylenebis(2-oxazoline), 2,2'-p- Phenylene bis(2)
-oxazoline) is preferred. These can be used alone or as a mixture of two or more. A part of the oxazoline derivative used in the present invention has the following formula () [In the formula, R′ represents a monovalent aliphatic, alicyclic or aromatic hydrocarbon group, and represents Ra, Rb, Rc and
Rd is the same as in equation (). ] It can also be used in place of the monooxazoline compound shown below, and is effective for reaction control, adjustment of crosslinking density, etc. The monovalent hydrocarbon group R' in formula () corresponds to the n-valent hydrocarbon group R in formula () made monovalent. Specific examples of such oxazoline compounds include 2-methyl-2-oxazoline, 2-ethyl-2-oxazoline, 2-propenyl-2-oxazoline, 2-phenyl-2-oxazoline,
-Tolyl-2-oxazoline, 2,5-dimethyl-2-oxazoline, 2,4-dimethyl-2-oxazoline, 2-phenyl-4-methyl-2-oxazoline, 2-phenyl-5-methyl-2-oxazoline etc. can be exemplified. Among these, 2-phenyl-2-oxazoline and 2-tolyl-2-oxazoline are preferred. The ratio of the monooxazoline compound used is preferably 30% to the polyoxazoline compound represented by formula ().
It is mol% or less, more preferably 25 mol% or less, particularly preferably 20 mol% or less. The halogenated bisphenols used in the present invention are compounds represented by the following formula (). In formula (), X is chlorine or bromine, and m represents 1 or 2. Specifically, the halogenated bisphenols represented by the formula () include 2,2'-bis(3-chloro-4-hydroxyphenyl)propane, 2,2-bis(3,5-dichloro-4- phenyl)propane, 2,2'-bis(3-bromo-4-hydroxyphenyl)propane, and 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane. In the present invention, the ratio of the oxazoline derivative to the halogenated bisphenol is such that the hydroxy equivalent of the halogenated bisphenol is 10 to 120 relative to the oxazoline equivalent of the oxazoline derivative.
%, more preferably 30 to 100%, particularly 50 to 90%. In the present invention, in addition to the above-mentioned oxazoline derivatives and halogenated bisphenols, a small amount of other components capable of addition reaction with the oxazoline derivatives and/or halogenated bisphenols may be used. Examples of the component include carboxylic acid,
Examples include intramolecular acid anhydrides, epoxy compounds, amine compounds, and hydroxy compounds. In the present invention, the oxazoline derivative and the halogenated bisphenols are used as protic acids with a Pka of 2.5 or less, esters of protic acids with a Pka of 1.0 or less,
The reaction is carried out by heating in the presence of a catalyst selected from Lewis acids and their complexes, alkyl halides, and iodine. Here, Pka is the value in an aqueous solution, and if there are two or more protons that can dissociate,
It represents the value for the first proton. Regarding the above catalyst, examples of protonic acids with Pka of 2.5 or less include sulfonic acids, inorganic protonic acids, etc., and examples of the sulfonic acids include methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, etc. However, examples of inorganic protonic acids include sulfuric acid, phosphoric acid, phosphorous acid, phosphinic acid, phosphonic acid, and perchloric acid. Examples of esters of protonic acids with Pka of 1.0 or less include sulfonic acid esters such as methyl benzenesulfonate, ethyl benzenesulfonate, methyl p-toluenesulfonate, and ethyl p-toluenesulfonate, and inorganic protonic acids such as dimethyl sulfate. Examples include esters of. Examples of Lewis acids and their complexes include titanium tetrachloride, tin tetrachloride, zinc chloride, aluminum chloride,
Examples include trifluoroborane and trifluoroborane ether complex. Examples of alkyl halides include methyl iodide, ethyl iodide, propyl iodide, butyl iodide, benzyl iodide, and benzyl bromide. These catalysts can be used alone or in combination of two or more. The amount of these catalysts used is not particularly limited, but is preferably 0.01 to 20 mol%, based on the oxazoline derivative used.
More preferably 0.05 to 15 mol%, particularly preferably
The amount is about 0.1 to 10 mol%. The reaction method includes, for example, physically intimately mixing the oxazoline derivative, halogenated bisphenols, and the catalyst (solid and/or liquid), heating and melting the mixture, and filling it into a mold of the desired shape. In the method of heat-reacting in a mold (one-component method), the oxazoline derivative and the halogenated bisphenol are individually melted, mixed using a mixing means such as a mixing head, and then heated to the reaction temperature in advance to form the desired shape. Examples include a method of directly injecting into a mold and causing a reaction (two-liquid mixing method). In the case of the above-mentioned two-component mixing method, a component mainly consisting of an oxazoline derivative and a halogenated bisphenol, and a component mainly consisting of a halogenated bisphenol and a secondary oxazoline derivative are heated and reacted in advance, The obtained two liquids can also be used. Further, in the case of the two-component mixing method, it is preferable that the catalyst be contained in the halogenated bisphenols or the component mainly containing the halogenated bisphenols. The reaction temperature varies depending on the type of oxazoline derivative, halogenated bisphenol and catalyst used, and their usage ratio, but is preferably 60 to 340 °C.
°C, more preferably 70-300 °C, particularly preferably
The temperature is about 80-260℃. The reaction temperature may be any time required to sufficiently cure the target resin, and this time varies depending on the type of raw materials used, the proportion used, the reaction temperature, etc., but is preferably 10 seconds to 60 minutes. , more preferably
It is about 20 seconds to 30 minutes, particularly preferably about 30 seconds to 15 minutes. The reaction can be carried out at normal pressure to elevated pressure, but in order to prevent water in the atmosphere and oxidative deterioration of the resin, nitrogen,
It is preferable to carry out under an inert gas atmosphere such as argon. The thus obtained thermosetting resin of the present invention may contain reinforcing materials such as carbon fibers and glass fibers, various fillers, fillers, pigments, coloring agents, oxidation stabilizers, ultraviolet absorbers, mold release agents, etc., as necessary. Additives may be added as appropriate. <Effects of the Invention> The specific halogenated bisphenols used in the present invention have a halogen at the ortho position of the hydroxy group, but are generally considered to be compounds that are difficult to react due to steric hindrance due to the halogen at the ortho position.
However, according to the present invention, halogenated bisphenols exhibit unexpectedly higher reactivity toward oxazoline derivatives than ordinary bisphenols, and can produce tough thermosetting resins in a shorter reaction time. Form. Furthermore, this thermosetting resin has low water absorption, excellent chemical resistance and flame retardancy, and also has extremely excellent hydrolysis resistance due to the formation of ether bonds through the curing reaction. It has great significance. Therefore, the thermosetting resin of the present invention is extremely useful in reaction molding, for example, two-component mixture type reaction molding. <Examples> Hereinafter, the present invention will be described in detail with reference to Examples, but the Examples are for illustrative purposes and the present invention is not limited thereto. In the examples, "part" means "part by weight", and the heat distortion temperature was measured using a DMA (dynamic thermomechanical property measuring device) at a heating rate of 10° C./min. Example 1 100 parts of 2,2'-m-phenylenebis(2-oxazoline), 2,2-bis(3,5-dichloro-
119 parts of 4-hydroxyphenyl)propane and p
- 4 parts of toluenesulfonic acid was placed in a glass reactor, and the reactor was purged with nitrogen and then heated to 180°C. The reaction started immediately, and after 50 seconds, it heated up to 240°C and hardened. The resulting resin was transparent, brown, and tough, and had a heat distortion temperature of 190°C. Add this resin to boiling water for 10 minutes.
When the water absorption rate was measured after soaking for one day, it was 4.3%, and the limiting oxygen index was 38.5%. Example 2 100 parts of 2,2'-m-phenylenebis(2-oxazoline), 2,2-bis(3,5-dichloro-
140 parts of 4-hydroxyphenyl)propane and 4 parts of ethyl benzenesulfonate were placed in a glass reactor, mixed well, purged with nitrogen, and heated to 180°C.
The reaction started immediately, and after 35 seconds, it heated up to 245°C and cured. The resulting resin was transparent, brown, and tough, and had a heat distortion temperature of 218°C. In addition, the limiting oxygen index was 38%, and the water absorption rate measured in the same manner as in Example 1 was
It was 4.0%. Comparative Example For comparison, in Example 1, 2,2-bis(4-hydroxyphenyl)propane [bisphenol] was used instead of 2,2-bis(3,5-dichloro-4-hydroxyphenylpropane). A] was used to conduct the following experiment. That is, 2,2'-m-phenylenebis(2-
oxazoline), 70 moles of 2,2-bis(4-hydroxyphenyl)propane, and 5 mole% of P-toluenesulfonic acid were placed in a glass reactor, purged with nitrogen, heated to 180°C, and reacted for 15 minutes. I let it happen. The resulting resin was brown and transparent, but its impact strength (without notches) was only 3 kg cm/cm.
It was only about one-tenth the amount of cured resin according to the invention. Further, the heat distortion temperature was 154°C, and the heat resistance was also low. Further, the limiting oxygen index of this resin was 31%, and the water absorption rate measured in the same manner as in Example 1 was 6.3%. Further, the reflux acetone insoluble portion was 78%, which was found to be lower in reactivity than the resin according to the present invention (approximately 100%). As a result, halogen-substituted bisphenol A
It is understood that by using bisphenol A, the reactivity is improved compared to using bisphenol A, and the heat resistance, water absorption, impact resistance, flame retardance, etc. of the resulting cured resin are significantly improved. Ru. Example 3 Raw materials were charged in the same manner as in Example 1, except that 4 parts of butyl iodide was used instead of p-toluenesulfonic acid as a catalyst, and the mixture was heated to 190°C. The reaction started immediately, and after 70 seconds it heated up to 265°C and cured. The resulting resin has a heat distortion temperature of 193℃,
It was extremely strong. Example 4 Raw materials were prepared in the same manner as in Example 2, except that 6 parts of iodine was used as a catalyst instead of ethyl benzenesulfonate, and the mixture was heated to 180°C. The reaction started immediately, and after 55 seconds, it heated up to 255°C and cured. The resulting resin had a heat distortion temperature of 213°C and was tough.

Claims (1)

[Claims] 1. The following formula () [Wherein, n represents an integer of 2 to 4, and R represents an n-valent aliphatic, alicyclic, or aromatic hydrocarbon group. However, when n=2, R may be a direct bond. Ra,
Rb, Rc and Rd are each hydrogen atom or carbon number 3
It represents a monovalent group selected from the following aliphatic hydrocarbon groups and aromatic hydrocarbon groups having 7 or less carbon atoms, and these may be the same or different. ] An oxazoline derivative represented by the following formula () and a halogenated bisphenol represented by the following formula (), [In the formula, A method for producing a thermosetting resin, characterized by carrying out a heating reaction in the presence of a catalyst.