JPH04146919A - Allylic oligomer of excellent curability - Google Patents

Abstract

PURPOSE:To obtain an allylic oligomer of excellent curability from inexpensive materials by a less laborious process by reacting three specified starting materials in specified mole fractions in the presence of a transesterification catalyst while distilling off the formed allyl alcohol. CONSTITUTION:An allyl ester-terminated oligomer of a number-average molecular weight Mn (in terms of PS) of 500-50000 as measured by GPC and a weight- average molecular weight Mw of 1000-1000000 is obtained by reacting starting materials of formulas I, II and III in the mole fractions represented by formulas IV and V in the presence of a transesterification catalyst while distilling off the formed allyl alcohol. The starting materials include compounds of formulas I, II (cis and trans) and formula III [wherein Ar is 1, 2-, 1, 3-or 1, 4-phenylene, 2, 6-2, 3-or 1, 5naphthalene; R' is an organic residue derived from a 3 C or lower alcohol; and Z is an organic residue derived from a hydroxypolyol having X+1 hydroxyl groups (wherein X is 1-8)]. In the relationships of formulas IV and V, a, b and c are the mole fractions of the starting materials of formulas I, II and III, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a novel allylic oligomer with excellent curability.

[Prior art] DAP resin, which uses diallyl phthalate (hereinafter abbreviated as DAP) as a monomer, is widely used in molding materials, decorative boards, laminates, etc., and has excellent electrical properties under high temperature and high humidity conditions. It is trusted because it does not deteriorate over a long period of time.

However, as the performance of machines and electrical parts used has improved, there has been an increasing demand for resins that maintain the current excellent performance while also having improved heat resistance, mechanical strength, and impact resistance.

In addition, DAP resin has two double bonds in its monomer, and if it is polymerized normally, it will gel at a low conversion rate. It is used by extracting it as a prepolymer, adding a polymerization initiator and filler to the prepolymer, and then using it for actual use. Therefore, how to efficiently produce prepolymers is an important issue, and the current state of the art is still insufficient, and there has been a desire to develop an efficient production method.

[Problem H to be solved by the invention] When diallyl terephthalate (hereinafter abbreviated as DAT), which has excellent symmetry, is used as a monomer, an improvement in heat resistance can be expected, but at present, secondary cured products of DAT is known to have inferior mechanical properties, such as brittleness, and has not yet been put into practical use.

Furthermore, JP-A No. 59-80409 discloses that DAT is copolymerized with an aromatic hydrocarbon having at least one hydrogen atom at the benzyl position, such as toluene or xylene, and is cured to provide excellent heat resistance and high mechanical strength. A method of synthesizing the prepolymer is described. However, in order to obtain such a copolymer, the polymerization method and reaction equipment must be devised, such as the need to blow out the heptamer 1 initiator and aromatic hydrocarbon from a special nozzle while stirring at high speed. Moreover, this method requires a large amount of initiator, and since it involves radical copolymerization, it has the disadvantage that it is difficult, if not impossible, to reuse the monomer.

It is also possible to perform polymerization using halogenated hydrocarbons, aldehyde derivatives, etc., which have relatively high chain transfer constants, but in this case too, radicals generated from the solvent will add to the allyl group, so-called Telomerization occurs and the performance as a polymer deteriorates.

In addition, diallylisophthalate resin is also known as a resin having a high monothermal property, but although it is produced industrially, the monomer price of this resin is always high and impractical.

In addition, a method using a special monomer such as naphthalene dicarboxylic acid noallyl ester has been proposed in a patent, but this method is also not put into practical use due to the high monomer cost.

Furthermore, it cannot be said that the productivity of the prepolymer has been improved in any of the methods.

Attempts have also been made to copolymerize DAP monomers with other monomers having double bonds, and some with good physical properties, such as copolymers with ethylene, are also known. However, this is also DA
Since the P monomer has two double bonds, it gels during the process, so polymerization must be stopped midway, and even if the physical properties are improved, monomer recycling, etc., may actually reduce productivity. It is often disadvantageous.

Unsaturated polyesters based on terephthalic acid are also known, but in this case maleic anhydride or fumaric acid must be added as unsaturated components, and the heat resistance of this part is insufficient and the glass transition point (Tg ) will not be very high.

Furthermore, allyl ester oligomers having an allyl ester group at the end and the following structure in which the interior is derived from a polyvalent saturated carboxylic acid and a polyvalent saturated alcohol are also known.

e112: CHCl120 (cOR'000BO)ゎC
OR'C00CH2C11''C!H2 Here, R' represents an organic residue derived from a polyvalent saturated carboxylic acid, and B represents an organic residue derived from a polyvalent saturated alcohol.

In this case, if terephthalic acid, which has excellent symmetry, is used as the polyvalent saturated carboxylic acid, a cured product with very excellent physical properties can be obtained. However, in order to improve physical properties, it is necessary to increase the molecular weight to a certain degree, but the higher the molecular weight, the lower the double bond concentration and the disadvantage that the polymerization rate becomes extremely slow.

JP-A-1-217024 discloses a polyallyl polyester resin containing a trihydric alcohol as an essential component and having a fumaric acid or maleic acid skeleton inside. However, in this case, the fumaric acid or maleic acid skeleton is too far inside the resin, which tends to cause distortion during curing.

Furthermore, since maleic anhydride is used as a raw material, the reaction solution is severely colored, and the acid value and hydroxyl value after the reaction are high, resulting in poor electrical properties.

[Means for solving the problem] As mentioned above, allyl ester oligomers having an allyl ester group at the end and an internal structure derived from a polyvalent saturated carboxylic acid and a polyvalent saturated alcohol have excellent symmetry. Although allyl ester oligomers using terephthalic acid as a polyvalent saturated carboxylic acid have the disadvantage of extremely slow curing speed, they yield cured products with very excellent physical properties.

As a result of investigating ways to eliminate this drawback, it was found that the allyl ester oligomer shown below has significantly improved curability while retaining the advantages of conventional allyl ester resins.

The oligomer of claim (1) is prepared by charging raw materials consisting of the following (a), (b) and (c) in the presence of a transesterification catalyst at a molar fraction expressed by the following relational formulas (i, ii). The polystyrene equivalent number average molecular weight (M, ) measured by GPC (gel permeation fist chromatography) method is 500 to 50.
000, and the weight average molecular weight (Mw) is 000~!
000000, which is an oligomer having an allyl ester at the end.

且粍(a) Ct12:CllCH20CO人、C0
0CH2CH"CH2(+) 'J R'0CO-CF
I=CH-COOR' (cis or trans) (c
) HOZ-(OB) Represents a radical derived from a lower alcohol of the number 3 or less, and Zi′;! x+1 piece (×
represents a carbon residue having 2 to 20 carbon atoms derived from a polyol having a hydroxyl group (an integer of 1 to 8).

Direct husband i, a≠0, b≠O ii, 1.02≦(a + b)/c≦10 However,
alb and C are raw materials (a), (b) and (
represents the molar fraction of c).

The oligomer of claim (2) is In the presence of a transesterification catalyst, the following (a').

Obtained by reacting the raw materials consisting of (b), (c) and (d) at a molar fraction expressed by the following relational expressions (++1+ and iii) and distilling off RO[l 1R'OH. , an allyl ester at the terminal characterized by having a polystyrene equivalent number average molecular weight (Mn) of 500 to 50,000 and a weight average molecular weight (Mw) of 1,000 to 1,000,000 as measured by GPC (gel permeation chromatography) method. It is an oligomer with

1 millimeter (a') ROCOA, C00R (b) R'0CO-CH=CIl-GOOR' (
cis or trans) (c) HOZ-(OR) , 5-naphthalene group, R1R' represents an organic residue derived from a lower alcohol having 3 or less carbon atoms, and Z represents x+1 (X is 1
represents an organic residue having 2 to 20 carbon atoms derived from a polyol having a hydroxyl group (an integer of 8 or less).

"K i, a≠0, b≠O ii, 1.02≦(a' + b)/c≦10 stones, 2
(a' - c) <d<16 (a' ten b) However,
a' blc and d are raw materials (a') and (b) respectively
, (c) and (d).

Here, specific examples of the compound (a) include diallyl terephthalate, diallyl isophthalate, diallyl phthalate, 2,6-naphthalene dicarboxylic acid diallyl ester, 1,5-naphthalene dicarboxylic acid diallyl ester, and 2,3-naphthalene dicarboxylic acid. There are acid diallyl esters, etc., and one type of these may be used, or several types or more may be used simultaneously to synthesize an oligomer. Also,
An aliphatic diallyl ester such as diallyl adipate may also be present within the range that does not cause any problem.

Specific examples of the compound (b) include diallyl maleate, diallyl fumarate, dimethyl maleate, dimethyl fumarate, diethyl maleate, and diisopropyl fumarate, and only one type of these may be used or , several or more types may be used simultaneously to synthesize oligomers.

Examples of polyols having two or more hydroxyl groups (c) include ethylene gelcol, 1,2-propylene glycol, 1,4-butanediol, 2,3-butanediol, neopentyl glycol, 1. [i-hexanediol, l, 4-cyclohexane dimetatool, l,
Dihydric alcohols containing aliphatic or aromatic rings such as 3-cyclohexanediol, p-xylylene glycol, and styrene glycol: ethylene oxide adducts of bisphenol-A, propylene oxide adducts to bisphenol, and ethylene oxide additions of hydroquinone. alkylene oxide adducts of diphenols such as propylene oxide adducts of hydroquinone and ethylene oxide adducts of resorcinol; diols containing ethers such as diethylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, and polypropylene glycol; Examples include aliphatic trihydric alcohols such as glycerin and trimethylolfurohan; aliphatic tetravalent or higher alcohols such as pentaerythritol and sorbitol. Only one type of these may be used, or several or more types may be used simultaneously to synthesize an oligomer.

In addition, as an industrially useful method, instead of the diallyl ester in (a), the dialkyl ester of the corresponding dicarboxylic acid (hereinafter referred to as (a')) and allyl alcohol [hereinafter referred to as (d)] may be used as an ester. In the presence of an exchange catalyst,
The above-mentioned allyl ester oligomer can be obtained by carrying out the reaction while distilling off the generated alkanol.

The alkyl group used here is preferably one that induces an alcohol with a lower boiling point than allyl alcohol,
Examples of such groups include methyl, ethyl, and isopropyl groups.

Moreover, the molecular weight of the obtained oligomer can be adjusted by changing the charging composition. If the molecular weight is too high, the viscosity of the polymerization solution will become too high during the polycondensation reaction, resulting in too high a risk of thermal polymerization. Also,
If it is too low, the expected physical property values will not be obtained.

The molecular weight of the oligomer obtained there was determined by GPC (
500 in terms of polystyrene equivalent number average molecular weight (closed) measured by gel permini/Yon chromatography) method.
-50,000, more preferably 800-10,000, and the weight average molecular weight (Mw) is 1,000-100,000.
, preferably within the range of 1,500 to 1,000,000.

As the transesterification catalyst to be used, conventionally known transesterification catalysts can be used, but particularly preferred are alkali metals, alkaline earth metals, oxides thereof, weak acid salts, Mn, U, Zn, Cd
, Zr, Pb, T1. These include oxides, hydroxides, inorganic acid salts, alcolades, and organic acid salts of Go and Sn, and organic tin compounds such as dibutyltin oxide, dioctyltin oxide, and dibutyltin dichloride.

The amount used should be such that allyl alcohol can be distilled off at an appropriate rate, although it will vary depending on the catalyst activity. - For boat fishing, 0.0001 to 1% by weight, particularly preferably 0.0001% to 1% by weight, based on the dialkyl ester of dicarboxylic acid.
．． 001-0.1% by weight is to be used.

In the embodiment of the reaction, when an allyl ester is used as a raw material, it is heated above the boiling point of allyl alcohol, and when an alkyl ester is used, it is heated above the boiling point of the corresponding alkanol to perform transesterification and generate oligomers. Advantageously, the allyl alcohol or alkanol produced is distilled out of the reactor by reactive distillation. Generally, the reaction is carried out under normal pressure or increased pressure, but it is also effective to increase the conversion rate of the reaction and to quickly distill off allyl alcohol or alkanol by reducing the pressure in the reaction system.

As mentioned above, when using allyl ester, if the reaction temperature is below the boiling point of allyl alcohol, the allyl alcohol cannot be effectively distilled off, and if the temperature is too high, thermal polymerization etc. Generally, the temperature is between 100 and 300°C, more preferably between 130 and 250°C.
Selected between ℃.

When an alkyl ester is used, the boiling points of the alkanol to be reacted with the allyl alcohol are close to each other, so if the reaction is heated to too high a temperature from the beginning of the reaction, the allyl alcohol may distill out together with the alkanol. Therefore, in addition to installing an efficient rectification column, the reaction temperature is generally 80-+50 at the initial stage of the reaction.
℃, more preferably between 90 and 130°C, after most of the alkanol has been distilled off, it is preferably between 100 and 300°C, more preferably between 130 and 250''C.

Furthermore, depending on the reaction temperature, a polymerization inhibitor such as hydroquinone or a coloring inhibitor may be allowed to coexist in the reaction solution.

The molar ratio of the raw materials used here needs to be used under certain restrictions. That is, the compound (c) is (
If it is used in too much excess relative to a) [or (a')] or (b), the oligomer ends will all become OH groups, making it impossible to cure. Also, if the amount is too low, the remaining monomer will be extremely large,
This is not preferred because it has no meaning in improving physical properties.

Therefore, the molar ratio of (a) [or (a'), (b), and (c) to be used is preferably selected from the range expressed by the following relational expression.

1,02≦(a+b)/c≦10, more preferably 1.1≦(a+b)/c≦2 Also, allyl alcohol (d) to be used when dialkyl ester of (a′) is used as a raw material If you ill,
If it is used in excess, the concentration of allyl alcohol remaining after the reaction will become high, which is not preferable. On the other hand, if it is too small, the resulting oligomer ends will not become allyl ester groups, which is not preferable.

Therefore, the usage amounts are (a'), (b), (c), (
It is desirable that the molar ratio of d) be within the range expressed by the following relational expression.

2 (a' - c) < d < 16 (a' + b) more preferably 4 (a' - c) < d < 8 (a' + b)
If the ratio of (a) [or (a') and (b) is too high, the curing speed will not be sufficiently improved, and if the ratio of (b) is too high, Heat resistance such as thermal decomposition temperature, mechanical properties, etc. will deteriorate significantly, so (a
) [or (a')] and (b) are preferably in the range of 0.3<a/b<100, more preferably 1<a/b<50.

Allyl ester oligomers having double bonds inside the molecule, which are obtained by transesterification using only esters as raw materials, are characterized by extremely low acid values and hydroxyl values. Due to this feature, it exhibits excellent electrical properties such as insulation resistance, dielectric constant, and arc resistance. It also has excellent hydrolysis properties such as alkali resistance.

Moreover, since a compound that is easily colored, such as maleic anhydride, is not used as a reaction raw material, a colorless and transparent allyl ester oligomer can be obtained after the reaction is completed.

Various methods can be used to take out the oligomer after the reaction is completed. For example, diols such as ethylene gelcol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, and 1°4-cyclohexane dimetatool provide aromatic dicarboxylic acids and highly crystalline polyesters. When using, it is also possible to distill off unreacted monomers under reduced pressure if necessary, and then cool, solidify, and pulverize. At this time, if it is necessary to distill off the monomer, at least 1 O
It is preferable to distill off at a pressure of m+IlBg or less, more preferably 5 mmHg or less, and a temperature of 300°C or less, even more preferably 250°C or less. Thereafter, the reaction solution after distillation is cooled and assimilated, and then passed through a pulverizer to easily form a powder.

The crushers used include Jaw Claso/Yargy Retriever Tarason Yar, Rotary Claso/Year, Attrition Mill, Edge Runner Ring Roll Mill, Ball Mill, Toni N Crusher, and Hough 7-Clason Yar.
Micron mills, micronizers, etc. can be used.

Furthermore, after one reaction is completed, it is also possible to directly transfer the reaction solution to a poor solvent, precipitate it, and take it out. The poor solvent used at this time dissolves the raw material alkyl ester and diol,
It is desirable to use a substance that does not dissolve the allyl ester oligomer produced, and aliphatic saturated alcohols or hydrocarbons are suitable as such substances. The aliphatic saturated alcohol or hydrocarbons desirably have a boiling point of 200°C or lower, preferably 150°C or lower, considering post-treatments such as drying, such as methanol, ethanol, isopropyl alcohol, n-propyl alcohol, etc. Alcohol, n-butyl alcohol, isobutyl alcohol, 2-
Butyl alcohol, tert-butanol, pentane,
Examples include hexane, heptane, octane, petroleum ether, etc., with methanol and petroleum ether being particularly preferred.

If the amount of poor solvent used is too small, not only will it not be possible to effectively recover unreacted raw materials, but the oligomer will be in the form of clumps and cannot be obtained as a powder. In addition, it is not preferable to use too much excess from an economical point of view;
More preferably, it is desirable to use about 2 to 10 times as much. As for the temperature at which the reaction solution is transferred, the reaction solution needs to be at a low temperature of 70°C (at which temperature it can flow). Also, if the temperature is too high, there is a risk of thermal polymerization of the oligomer, so the temperature should be 80-300°C. °C, more preferably between 10
It is preferable to choose between 0 and 250°C. If the temperature on the poor solvent side is too high, it will not be possible to powderize the oligomer, and if the temperature is too low, it will not be an economical method considering the cost of cooling, etc.
The temperature is more preferably 10 to 80°C than C1.

In addition, if diols such as l,2-propylene glycol or 1,3-butanediol are used as raw materials, or if the molecular weight of the produced sitaallyl ester oligomer is small, it will be a viscous liquid at room temperature; It can be purified by vacuum distillation and extraction.

Furthermore, it can also be used in the presence of a diallyl ester monomer, which is industrially more advantageous.

The molecular weight of the oligomer described here was measured by GPC using the following method.

5HODEX column AC-80P, 802.804.
One 80Ei tube was connected in series in this order, chloroform was used as the solvent, the column temperature was 25'C, and the flow rate was 1. θ
Measured in m/mln.

(1) First, using at least 10 types of commercially available standard polystyrene whose average molecular weights were known, the retention time of each was determined along with the DAT monomer. A calibration curve was created by approximating the relationship between average molecular weight and retention time using a cubic curve or a broken line.

■ Dissolve 20 mg of sample in 20 ml of chloroform,
Inject 0.5 ml through the line filter into the column using a loop injector. Based on the obtained elution curve data and the calibration curve created in ①, Shimadzu CR-
M□ and h are automatically calculated in a data processor such as 3A. Here, the peak was divided at intervals of 10 seconds, and the molecular weight at each division point was calculated using the following formula with MIN and the height of the peak as H2.

Σ Ho Σ (H1/M+) Σ Hl The oligomer thus obtained has excellent bending strength and impact resistance, as well as a fast curing speed.

This new oligomer can be used by blending fillers, polymerization accelerators, polymerization inhibitors, internal mold release agents, coupling agents, pigments, and other additives to the extent that physical properties are not impaired, as desired. Molding processability or physical properties of molded articles can be improved.

Furthermore, since this oligomer has a moderate amount of double bonds, it can be used in combination with unsaturated polyester resins and diallyl phthalate resins, and can also be used as a crosslinking agent for EPR, elathrene, synthetic rubber, etc.

The present invention will be explained in more detail below.

[Example] Support! 400 g of noaryl terephthalate (1 dimethyl fumarate) 4B in a three-piece flask equipped with a top distillation device.
8g1 98.9g of propylene glycol and 0.40g of dibutyltin oxide were charged and heated to 170°C under a nitrogen stream.
The resulting methanol was distilled off. When the distillate reaches about 100g, the inside of the reaction system is gradually
The pressure was reduced to 0 mmHg, and the distillation rate of methanol and allyl alcohol was increased. When almost no distillate came out, the inside of the reaction system was adjusted to 2 mmHg, and the reaction was continued for an additional 1 hour, and the reaction product was cooled.

Table 1 shows the physical properties of the obtained oligomer.

-I ring-- Example except that aromatic allyl ester (monomer a), unsaturated dibasic acid dialkyl ester (monomer b), and polyol 1.2 (monomer C) were changed as shown in Table 1. Table 1 shows the physical properties of the oligomer synthesized in substantially the same manner as Example 1.

315.4 g of dimethyl terephthalate, dimethyl fumarate 4B,
8g of methanol, 98.9g of propylene glycol, 400g of allyl alcohol, and 1.5g of dibutyltin oxide were charged and heated to 150°C under a nitrogen stream, and the methanol produced (methanol was distilled off. (The amount of methanol lost in the distillate was replaced by distillation.) When the methanol in the distillate ran out, the reaction temperature was increased to 180°C.
The allyl alcohol was distilled off. At the stage when the distillation rate of allyl alcohol becomes slow, the inside of the reaction system is
The pressure was reduced to mmHg to increase the rate of distillation of allyl alcohol. After excess allyl alcohol was distilled off, the reaction was continued for an additional hour, and the reaction product was cooled to obtain an allyl oligomer almost the same as in Example 1.

(2) Preparation of samples for curing 200 g of the oligomers obtained in Examples 1 to 6 and Comparative Example 1 were each taken, 4.0 g of dicumyl peroxide was added, and the mixture was dissolved at 50°C.

(2) The composition obtained by molding by casting was placed on a heating plate at 160°C, and the time until it stopped becoming stringy was measured, and the gel time was determined.

Further, a predetermined amount of a curing sample was taken and cured at 160° C. by cast polymerization using a cellophane-covered glass plate.

The physical property values of the obtained molded article are also shown in Table-1.

[Effects of the Invention] The present invention provides a novel allylic oligomer with excellent curability that can be obtained using inexpensive raw materials and a method with little labor, and the cured product thereof has excellent physical properties.

Patent applicant: Showa Denko Co., Ltd. teenager Reason Man autumn Shining , -11 years old Xiong Xi

Claims (1)

[Claims] (1) In the presence of a transesterification catalyst, the following (a), (
The raw materials consisting of b) and (c) are expressed by the following relational expression (i, i
The polystyrene equivalent number average molecular weight (M_n) measured by GPC (gel permeation chromatography) method, which is obtained by reacting at the molar fraction represented by i) and distilling off allyl alcohol, is from 500 to
50,000, and the weight average molecular weight (m_w) is 100
An oligomer having an allyl ester at a terminal, characterized in that the number is 0 to 1,000,000. ￥Raw materials￥ (a) CH_2=CHCH_2OCOArCOOCH_
2CH=CH_2(b)R'OCO-CH=CH-CO
OR' (cis or trans) (c) HOZ-(OH)
_x However, Ar represents a 1,2-, 1,3- or 1,4-phenylene group, or a 2,6-, 2,3- or 1,5-naphthalene group, and R' is a carbon number of 3 or less. It represents an organic residue derived from a lower alcohol, and Z represents an organic residue having 2 to 20 carbon atoms derived from a polyol having x+1 (x is an integer from 1 to 8) hydroxyl groups. ￥Relational expression￥ i, a≠0, b≠0 ii, 1.02≦(a+b)/c≦10 However, a, b and c are raw materials (a) and (b) respectively
and represents the molar fraction of (c). (2) In the presence of a transesterification reaction catalyst, the following raw materials (a'), (b), (c) and (d) are converted into
ii) ROH by reacting at the molar fraction represented by
, the polystyrene equivalent number average molecular weight (M_n) measured by GPC (gel permeation chromatography) method obtained by distilling off R'OH is 500.
~50000, and the weight average molecular weight (M_w) is 10
00 to 1,000,000. An oligomer having an allyl ester at its terminal, characterized in that the number is from 00 to 1,000,000. ¥Raw materials¥ (a') ROCOArCOOR (b) R'OCO-CH=CH-COOR' (cis or trans) (c) HOZ-(OH)_x (d) Allyl alcohol However, Ar is 1,2-, 1 , 3- or 1,4-phenylene group, or 2,6-, 2,3- or 1,5-naphthalene group, and R and R' are organic residues derived from lower alcohols having 3 or less carbon atoms. , Z is x+1 (x is 1
represents an organic residue having 2 to 20 carbon atoms derived from a polyol having a hydroxyl group (an integer of 8 or less). ￥Relational expression￥ i, a≠0, b≠0 ii, 1.02≦(a′+b)/c≦10 iii, 2(a′-c)<d<16(a′+b) However, a′ , b, c and d are the raw materials (a') and (b
), (c) and (d).