CN1944441A - Sesqui-siloxane containing benzoxazinyl group and its composition and preparing method - Google Patents

Abstract

The invention provides a preparation method and composition of silsesquioxane containing benzoxazine groups. In the method, the phenyl silsesquioxane compound containing primary amino groups is used as an amine source, and phenol and aldehyde are condensed to form a ring to obtain silsesquioxane containing benzoxazine groups. Such compounds can be mixed with thermosetting resins such as epoxy resins, phenolic resins, bismaleimide resins, cyanate resins, benzoxazine resins, oxazoline resins, polyimide resins, or their combinations , to obtain a composition of silsesquioxane containing benzoxazine groups. The silsesquioxane containing benzoxazine groups obviously improves the heat resistance of the cured product of the obtained composition.

Description

Silsesquioxane containing benzoxazine group, its composition and preparation method

technical field

The invention relates to a synthetic method of a class of silsesquioxanes. More specifically, it relates to silsesquioxanes containing benzoxazine groups, compositions and methods of preparation thereof.

Background technique

Polyhedral oligomeric silsesquioxane (POSS) is a member of the silsesquioxane family and is a new class of nanomaterials. The molecular diameter of POSS is very small, about 1-3 nanometers, and its cage structure resembles silicon dioxide (Si:O=1:1.5). It can be regarded as the smallest unit of silicon dioxide (silica) or "molecular silica". POSS has the characteristics of high temperature and strength, excellent flame retardancy, and low density; the eight vertices (or "corners") of its cage structure can bond various organic functional groups to become POSS organic Functional monomers can be regarded as a type of organic-inorganic hybrid molecules. Known organic functional groups such as amine group, epoxy group, ester group, phenyl group, vinyl group, cyclohexyl group, methyl group, isobutyl group, etc., and the organic groups at each corner can be the same or different. This endows POSS with good compatibility to the organic material matrix, and can even be grafted on the side chain of the polymer through chemical bonds or directly polymerized into the main chain and cross-linked network of the polymer to prepare blended, copolymerized or Crosslinked hybrid polymers or polymer composites.

The American Hybridplastics company has applied for and obtained a patent in China (Chinese patent application number: 00813875.3), covering a variety of synthetic methods; Japan's Nippon Steel Chemical Co., Ltd. has applied for a patent involving POSS synthesis (Chinese patent application number : 03154435.5), the base-catalyzed method of mainly preparing POSS containing epoxy groups, acrylate groups, etc. The "Preparation Method of Amino-Phenyl Silsesquioxane" (Chinese Patent Application No. 200610080871.4) proposed by the present inventor discloses a new method for preparing amino-containing phenyl silsesquioxane.

The research group of Professor Zhang Fengzhi in Taiwan took the lead in preparing the nanocomposite material of benzoxazine resin and POSS. They first synthesized the POSS molecule (BZ-POSS) with the oxazine ring structure through the following two routes: one through POSS The silicon-hydrogen bond carried by the molecule undergoes hydrosilylation with the oxazine monomer with an allyl group; the second is to react the POSS molecule with an alkyl primary amine group with formaldehyde and phenol according to a certain molar mass ratio to form Oxazine ring structure. Then BZ-POSS is mixed with pure oxazine monomer, and then cured at elevated temperature to obtain a nanocomposite material of POSS/benzoxazine resin. The results showed that compared with the matrix resin, the introduction of POSS molecules increased the glass transition temperature and thermal degradation temperature of oxazine resins, but at the same time, it was found that BZ-POSS molecules had poor compatibility with benzoxazine monomers and were easy to agglomerate , a phase-separated structure is formed in the cured product. When the content of BZ-POSS increases to a certain extent, the thermal performance of the composite system will decrease instead. In the research, they also tried to use POSS with non-reactive isobutyl groups and benzoxazine to directly melt blend to prepare composite materials. The results showed that this type of POSS molecule was very poorly compatible with the matrix resin, so its The introduction degrades the performance of the matrix resin. (see specifically: 1. Y.J.Lee, S.W.Kuo, T.C.Su, J.K.Chen, C.W.Tu, F.C.Chang, Syntheses, thermal properties, and phase morphologies of novel benzoxazine functionalized with polyhedral oligomeric silsesquioxane (POSS) nanocomposites, 4(04, 5 18): 6321-6331; 2. Y.J.Lee, J.M.Huang, S.W.Kuo, J.K.Chen, F.C.Chang, Synthesis and characterizations of a vinyl-terminated benzoxazine monomer and its blending with polyhedral oligomeric silsesquioxane(POSS), 6(05, 6 7): 2320-2330)

The relevant technical background of benzoxazine can refer to the inventor's "N-allyl-containing benzoxazine intermediate and composition and preparation method thereof" (Chinese Patent Application No. 03146797.0) and "phenolphthalein type benzoxazine Oxazine intermediates and compositions and their preparation methods" (Chinese patent application number: 200510087724.5). In various publications, preparation compositions between benzoxazines, benzoxazines and other thermosetting resins including benzoxazine intermediates, epoxy resins, unsaturated polyester resins have been reported , vinyl resin, bismaleimide resin, phenolic resin, polyurethane resin, cyanate resin or thermosetting polyimide, etc. are thermosetting resins and their compositions well known to those skilled in the art. The introduction of benzoxazine can improve the heat resistance of the composition, or reduce the cost, or improve the processability. Benzoxazines and their compositions have broad application prospects in many fields such as composite materials, printed circuit boards, electronic packaging, and coatings.

But so far there is no report on the preparation of benzoxazine group-containing silsesquioxane by using primary aminophenyl silsesquioxane, and there is no report on the preparation of composition by using it.

Contents of the invention

The object of the present invention is to propose a preparation method and composition of silsesquioxane containing benzoxazine groups. In the method, the phenyl silsesquioxane compound containing primary amino groups is used as an amine source, and phenol and aldehyde are condensed to form a ring to obtain silsesquioxane containing benzoxazine groups. Such compounds can be mixed with thermosetting resins such as epoxy resins, phenolic resins, bismaleimide resins, cyanate resins, benzoxazine resins, oxazoline resins, polyimide resins, or their combinations , to obtain a composition of silsesquioxane containing benzoxazine groups.

The structural formula of the silsesquioxane containing benzoxazine group of the present invention is as follows:

(RSiO _1.5 )n

where n is 6, 8, 12

Wherein R is the following structure:

In the formula, all of R1, R2, R3, and R4 are hydrogen; or one of R1, R2, R3, and R4 is an alkyl, allyl, or vinyl group with 1 to 10 carbon atoms, and the remaining three are hydrogen; R2, R4 is an alkyl group having 1 to 10 carbon atoms, and R1 and R3 are hydrogen.

The preparation method of the silsesquioxane containing benzoxazine group proposed by the present invention, the silsesquioxane containing amine group, phenol and aldehyde are prepared by solution or fusion synthesis method containing benzoxazine group Silsesquioxane, is characterized in that: amine adopts the silsesquioxane containing amino group, particularly octaaminophenyl silsesquioxane; The molar ratio of phenolic hydroxyl group, amino group, aldehyde functional group in the reactant It is (1～15):1:(2～4).

The preparation method of the silsesquioxane containing benzoxazine group proposed by the present invention can adopt the synthetic method of benzoxazine well known to those skilled in the art, including the following two methods:

(1) Solution synthesis method: phenol, silsesquioxane containing amino group, aldehyde (formaldehyde aqueous solution or paraformaldehyde) according to the molar ratio (1～15) of phenolic hydroxyl group, amino group, aldehyde functional group: 1: (2～4) Quantitatively, after dissolving phenol and primary amine in the solvent and mixing evenly, then adding aldehyde in portions, and heating up and refluxing for 2 to 10 hours to complete the reaction; washing with deionized water, and concentrating the resulting solution, Precipitate in hexane, filter, remove residual solvent, and dry to obtain silsesquioxane containing benzoxazine groups.

(2) Melt synthesis method: phenol, amino-containing silsesquioxane, aldehyde (paraformaldehyde or formaldehyde aqueous solution) according to the molar ratio of phenolic hydroxyl, amino, and aldehyde functional groups (1～15): 1: (2~4) Quantitatively, at low temperature (0°C~5°C), mix phenol and amino-containing silsesquioxane evenly in advance, then add aldehyde, heat up and reflux for 2~10 hours, and then end the reaction; Wash with ion water, dissolve in solvent, precipitate in hexane, filter, remove residual solvent, and dry to obtain silsesquioxane containing benzoxazine group.

The present invention can obtain a series of silsesquioxanes containing benzoxazine groups by adopting a solution synthesis method or a melt synthesis method.

The preparation method of the silsesquioxane containing benzoxazine group proposed by the present invention, the amino silsesquioxane used includes octaaminophenyl silsesquioxane, hexaamino phenyl silsesquioxane Silicone, Dodecylaminophenylsilsesquioxane, Polyaminophenyloligomericsilsesquioxane.

The preparation method of the silsesquioxane containing benzoxazine group that the present invention proposes, the phenol that adopts comprises phenol, monoalkyl substituted phenol, such as p-cresol, m-cresol, o-cresol, nonylphenol, Polyalkylated phenols, such as 3,5-dimethylphenol, etc. Unsaturated substituted phenols, such as o-allylphenol, 4-vinylphenol, etc., halogenated phenols, such as p-chlorophenol, etc., p-methoxy phenol, and other monophenolic compounds well known to those skilled in the art.

The preparation method of the silsesquioxane containing benzoxazine group that the present invention proposes, the phenol that adopts comprises phenol, p-cresol, m-cresol, o-cresol, nonylphenol, 3,5-dimethyl Phenol, o-allylphenol, 4-vinylphenol, p-chlorophenol.

In the preparation method of the silsesquioxane containing benzoxazine groups proposed by the present invention, the aldehyde used is aqueous formaldehyde or paraformaldehyde well known to those skilled in the art.

The preparation method of the silsesquioxane containing benzoxazine group that the present invention proposes, the solvent that adopts is benzene, toluene, xylene, dioxane, tetrahydrofuran (THF), dimethyl Formamide, dimethyl sulfoxide, ethanol, butanol, isopropanol, etc.

The composition prepared by mixing silsesquioxane containing benzoxazine groups with other thermosetting resins proposed by the present invention, other thermosetting resins include: benzoxazine intermediates, epoxy resins, unsaturated polyester resins, ethylene at least one of base resin, bismaleimide resin, oxazoline resin, phenolic resin, polyurethane resin, cyanate resin, thermosetting polyimide, aryl acetylene resin or furan resin; The silsesquioxane weight content of the oxazine group is 1%-15% of the composition.

The preparation method of the composition prepared by mixing the silsesquioxane containing benzoxazine groups and other thermosetting resins proposed by the present invention includes mixing methods known to those skilled in the art such as mechanical mixing, solution mixing or melt mixing to obtain combination.

The cured product prepared by mixing the benzoxazine group-containing silsesquioxane and other thermosetting resins prepared by the present invention has POSS evenly dispersed in the matrix, and the cured product has high heat resistance.

The composition prepared by mixing the benzoxazine group-containing silsesquioxane and other thermosetting resins proposed by the present invention can be applied to the processing techniques of various thermosetting resins and the molding techniques of composite materials well known to those skilled in the art. For example: coating process, impregnation process, pultrusion process, also can adopt rotary molding process (RTM) etc.; The reinforcing material that prepares composite material uses comprises the various fibers that those skilled in the art such as glass fiber, carbon fiber are familiar with, also can adopt Nano-reinforcing fillers such as carbon nanotubes and nano-inorganic fillers (such as nano-titanium dioxide, organically modified clay, etc.) can be used; the heat resistance and flame retardancy of the obtained products or composite materials are significantly improved; it can be applied to composite materials, printed circuits, etc. boards, electronic packaging, coatings and many other fields.

Detailed ways

Example 1

Get 2 grams (0.173mmol) octaaminophenylsilsesquioxane (OAPS for short), p-cresol, paraformaldehyde according to the molar ratio of phenolic hydroxyl, amino, aldehyde functional group 1: 1: 2 quantification, first Dissolve p-cresol and OAPS in dioxane and mix evenly, then add aldehydes in portions, and heat up and reflux for 2 to 10 hours to complete the reaction; wash with deionized water, concentrate the resulting solution, and dissolve in hexane Precipitate, filter, remove residual solvent, and dry to obtain 0.3 g of p-cresol-type octabenzoxazinylsilsesquioxane (cBZ-POSS), with a yield of 8%.

Example 2

As described in Example 1, only p-cresol and paraformaldehyde were quantified according to the molar ratio of phenolic hydroxyl group, amino group, and aldehyde functional group in a ratio of 2:1:2 to finally obtain about 0.5 g of cBZ-POSS with a yield of 13%.

Example 3

As described in Example 1, only p-cresol and paraformaldehyde were quantified according to the molar ratio of phenolic hydroxyl group, amino group, and aldehyde functional group of 5:1:3, and finally about 0.84 g of cBZ-POSS was obtained, with a yield of 22%.

Example 4

As described in Example 1, only p-cresol and paraformaldehyde were quantified according to the molar ratio of phenolic hydroxyl group, amino group, and aldehyde functional group of 10:1:3, and finally about 1.22 g of cBZ-POSS was obtained, with a yield of 32%.

Example 5

As described in Example 1, only p-cresol and paraformaldehyde were quantified according to the molar ratio of phenolic hydroxyl group, amino group, and aldehyde functional group of 15:1:4, and finally about 1.07 g of cBZ-POSS was obtained, with a yield of 28%.

Example 6

Get 5 grams (0.173mmol) OAPS, p-cresol, paraformaldehyde are quantified according to the molar ratio of phenolic hydroxyl group, amino group, aldehyde functional group 1: 1: 2, first p-cresol and OAPS are mixed, after OAPS dissolves completely, Cool down to 0-5°C, then add aldehyde in portions, and heat up to reflux for 6 hours to end the reaction; dissolve in ethyl acetate, precipitate in hexane, filter, remove residual solvent, and dry to obtain octabenzone Oxazinylsilsesquioxane (cBZ-POSS) 0.57 g, yield 15%.

Example 7

As described in Example 6, just take 2 grams (0.173mmol) of OAPS, and p-cresol and paraformaldehyde are quantified according to the molar ratio of phenolic hydroxyl, amino, and aldehyde functional groups of 13.4:1:2.89, and finally cBZ-POSS is about 2.9 g, 75% yield.

Example 8

As described in Example 6, just get 2 grams (0.173mmol) of OAPS, and p-cresol and paraformaldehyde are quantified according to the molar ratio of phenolic hydroxyl, amine, and aldehyde functional groups of 15:1:4, and finally cBZ-POSS about 2.6 g, 68% yield.

Example 9

As described in Example 7, except that phenol was substituted for p-cresol, about 1.56 g of phenolic octabenzoxazinyl silsesquioxane (BZ-POSS) was finally obtained, with a yield of 43%.

Example 10

As described in Example 7, only p-nonylphenol was substituted for p-cresol, and finally about 3.06 g of p-nonylphenol-type octabenzoxazinylsilsesquioxane (nBZ-POSS) was obtained, with a yield of 57%.

Example 11

As described in Example 7, except that p-cresol was replaced by o-allylphenol, about 2.63 g of p-nonylphenol-type octabenzoxazinylsilsesquioxane (nBZ-POSS) was finally obtained, with a yield of 63%.

Example 12

Bisphenol A aniline benzoxazine (BA) prepared by bisphenol A, aniline, and formaldehyde is used for curing, and the curing segment temperature and time: 1 hour at 100°C, 1 hour at 130°C, 1 hour at 160°C 1 hour, 3 hours at 180°C, 3 hours at 200°C, and 1 hour at 220°C to obtain a cured product; measured by a dynamic viscoelastic analyzer (DMA for short), the glass transition temperature (Tg) is 177°C.

Example 13

99 parts of BA and 1 part of octabenzoxazinyl silsesquioxane (abbreviated as cBZ-POSS) were dissolved in THF at room temperature, and after mixing for 1 hour, the THF was removed in vacuo to obtain the BA/cBZ-POSS composition. Curing was carried out under the curing conditions described in Example 12 to obtain a cured product; as measured by a dynamic viscoelastic analyzer (DMA for short), its glass transition temperature (Tg) was 177.5°C.

Example 14

95 parts of BA and 5 parts of cBZ-POSS were obtained according to the method described in Example 13; the glass transition temperature (Tg) was 180°C as measured by a dynamic viscoelastic analyzer (DMA for short).

Example 15

90 parts of BA and 10 parts of cBZ-POSS were obtained according to the method described in Example 13; the glass transition temperature (Tg) was 183°C as measured by a dynamic viscoelastic analyzer (DMA for short).

Example 16

85 parts of BA and 15 parts of cBZ-POSS were obtained according to the method described in Example 13; the glass transition temperature (Tg) was 194°C as measured by a dynamic viscoelastic analyzer (DMA for short).

Example 17

15 parts of E-51 type epoxy resins, 60 parts of BA and 15 parts of cBZ-POSS, obtain cured product according to the method described in embodiment 13; Measure through dynamic viscoelastic analyzer (being called for short DMA), its glass transition temperature ( Tg) was 185°C.

Example 18

Mix 40 parts of 2,2'-(1,3-phenylene)-bis(4,5-dihydro-oxazoline) (PBO), 45 parts of BA and 15 parts of cBZ-POSS, heat up to 140°C, Mix the PBO/BA/cBZ-POSS system evenly, and cool to obtain the composition. Curing was carried out according to the curing conditions described in Example 12 to obtain a cured product; as measured by a dynamic viscoelastic analyzer (DMA for short), its glass transition temperature (Tg) was 190°C.

Claims (3)

1. The structural formula of silsesquioxane containing benzoxazine groups is as follows: (RSiO _1.5 )n where n is 6, 8, 12 Wherein R is the following structure:

In the formula, all of R1, R2, R3, and R4 are hydrogen; or one of R1, R2, R3, and R4 is an alkyl, allyl, or vinyl group with 1 to 10 carbon atoms, and the remaining three are hydrogen; R2, R4 is an alkyl group having 1 to 10 carbon atoms, and R1 and R3 are hydrogen. 2. According to the preparation method of benzoxazine group-containing silsesquioxane according to claim 1, benzoxazine-containing silsesquioxane, phenol and aldehyde are prepared by solution or melt synthesis The silsesquioxane of oxazine group is characterized in that: amine adopts the silsesquioxane containing amino group, especially octaaminophenyl silsesquioxane; In the reactant, phenolic hydroxyl group, amine group, aldehyde The molar ratio of the functional group is (1-15): 1: (2-4). 3. Compositions prepared by mixing silsesquioxane containing benzoxazine groups with other thermosetting resins. Other thermosetting resins include: benzoxazine intermediates, epoxy resins, unsaturated polyester resins, vinyl resins , at least one of bismaleimide resin, oxazoline resin, phenolic resin, polyurethane resin, cyanate resin, thermosetting polyimide, aryl acetylene resin or furan resin; The silsesquioxane weight content of the group is 1%-15% of the composition.