KR101456288B1 - Thermoplastic organic-inorganic hybrid material and process for production of the same - Google Patents

Abstract

An object of the present invention is to provide an organic-inorganic hybrid material having excellent transparency, heat resistance and mechanical strength, being soluble in an organic solvent, having melt flowability, and having excellent moldability, and a method for producing the same. In order to solve the above problems, according to the present invention, a polymerizable functional group-modified inorganic particle in which a water-soluble group having a polymerizable functional group is covalently bonded to a hydroxyl group on the surface of an inorganic particle and a polymerizable monomer which is a thermoplastic polymer by polymerization are copolymerized In the thermoplastic organic-inorganic hybrid material, the polymerizable functional group-modified inorganic particles are covalently bonded to a part of the hydroxyl groups on the surface of the inorganic particles with a modifying group having the polymerizable functional group.

Thermoplastic organic-inorganic hybrid materials, polymerizable functional groups, inorganic particles

Description

TECHNICAL FIELD [0001] The present invention relates to a thermoplastic organic-inorganic hybrid material and a method of manufacturing the same. BACKGROUND ART [0002]

The present invention relates to an organic-inorganic hybrid material excellent in heat resistance, heat resistance, transparency, surface characteristics (surface hardness) and mechanical strength, solubility in organic solvents, and melt flowability and excellent moldability.

Conventionally, attention has been paid to an organic-inorganic hybrid material in which an organic phase and an inorganic phase are finely and homogeneously dispersed. Such an organic-inorganic hybrid material can have excellent properties such as high mechanical strength, small dispersed particles, and transparency because the light is not dispersed.

As a method for producing such an organic-inorganic hybrid material, a method of hydrolyzing a metal alkoxide (hereinafter referred to as "sol-gel method") under the coexistence of an organic polymer is widely used (for example, Non-Patent Document 1). Since the organic-inorganic hybrid material produced by the sol-gel method is precipitated from a homogeneous solution, the organic phase and the inorganic phase are finely dispersed to the molecular level, and a very homogeneous material can be obtained. In addition, since the sol-gel method does not require a high temperature, there is little possibility that the organic phase is altered by heat.

However, in the organic-inorganic hybrid material produced by the sol-gel method, water is formed by dehydration condensation in the sol-gel reaction, and cracks are liable to occur when the water is removed. For this reason, it is difficult to produce an organic-inorganic hybrid material having a high modulus of elasticity by increasing the proportion of the inorganic phase. Further, since the metal alkoxide is expensive, there has been a problem that the manufacturing cost is increased.

Therefore, an organic-inorganic hybrid material in which a functional group having an acrylic functional group is covalently bonded to a hydroxyl group on the surface of silica or the like and an acrylic monomer is copolymerized has been proposed (Patent Document 1). Since the organic-inorganic hybrid material uses polysilicic acid as the inorganic material source, the raw material cost as the inorganic material source becomes very low, and it is possible to supply the organic-inorganic hybrid material in a large amount. Further, since the sol-gel reaction is not used, cracks and the like hardly occur even when the proportion of the inorganic phase is increased, and it is easy to produce a homogeneous bulk material. In addition, by appropriately selecting the copolymerization ratio, it becomes possible to control the ratio of the organic phase to the inorganic phase in the organic-inorganic hybrid material.

On the other hand, an organic-inorganic hybrid material (nanocomposite) having no covalent bond between the inorganic particles and the organic polymer has been proposed. However, since there is no interaction between the inorganic particles and the organic polymer, It is difficult to synthesize a material having transparency and excellent mechanical strength by uniformly dispersing it (Patent Document 2).

Non-Patent Document 1: J. Phys. Chem., 93, 6270 (1989)

Patent Document 1: Japanese Patent Application Laid-Open No. 2004-331790

Patent Document 2: Japanese Patent Application Laid-Open No. 2004-131702

DISCLOSURE OF INVENTION

Technical Problems to be Solved by the Invention

The organic-inorganic hybrid material described in Patent Document 1 can provide excellent transparency and mechanical strength. However, since it is difficult to dissolve in an organic solvent and does not have melt fluidity, the organic- It has been pointed out that molding can not be carried out by using a molding technique. For this reason, in order to perform molding, the resin must be polymerized in a mold or must be molded by carving, resulting in a cost for molding and limited use thereof.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional circumstances, and an object of the present invention is to provide a resin composition which not only has excellent heat resistance, transparency, surface characteristics (surface hardness) and mechanical strength but also is soluble in organic solvents, -Inorganic hybrid material and a method for producing the same.

Means for solving the problem

The inventors of the present invention have conducted extensive studies in order to solve the problem of moldability, which is a problem of the invention described in the above-mentioned Patent Document 1. As a result, not all the hydroxyl groups present in the inorganic particles are modified by a water-soluble group having a polymerizable functional group, but the inorganic particles modified with only a part of the hydroxyl groups are used and are copolymerized with the monomers, Has a melt flowability and is a thermoplastic organic-inorganic hybrid material excellent in moldability, and has completed the present invention.

That is, in the thermoplastic organic-inorganic hybrid material of the present invention, the polymerizable functional group-modified inorganic particle in which a water-soluble group having a polymerizable functional group is covalently bonded to the hydroxyl group on the surface of the inorganic particle and a polymerizable monomer as a thermoplastic polymer by polymerization are copolymerized Wherein the polymerizable functional group-modified inorganic particles are characterized in that a part of the hydroxyl groups on the surface of the inorganic particles is covalently bonded to the functional group having the polymerizable functional group in the thermoplastic organic-inorganic hybrid material.

In the thermoplastic organic-inorganic hybrid material of the present invention, since inorganic particles having a hydroxyl group such as inorganic fine particle sol or polysilicic acid are used as an inorganic material source, the raw material cost becomes very low. Further, since the organic phase is covalently bonded to the hydroxyl group on the surface of the inorganic particles, peeling phenomenon or the like at the organic-inorganic interface is unlikely to occur and excellent heat resistance, transparency, surface characteristics (surface hardness) and mechanical strength are obtained. Moreover, since dehydration condensation such as sol-gel reaction does not occur, cracks and the like are hardly generated even when the proportion of the inorganic phase is increased, and it is easy to produce a homogeneous bulk material.

In addition to these characteristics, the thermoplastic organic-inorganic hybrid material of the present invention is soluble in an organic solvent, has a melt flowability, and is also characterized by excellent moldability. The reason for this is as follows. That is, although the thermoplastic organic-inorganic hybrid material of the present invention is formed by copolymerizing the polymerizable functional group-modified inorganic particles and the polymerizable monomer, the polymerizable functional group-modified inorganic particles may have a structure in which only a part of the hydroxyl groups on the surface of the inorganic particles have a polymerizable functional group (In other words, unreacted hydroxyl groups remain in the polymerizable functional group-modified inorganic particles). As a result, the number of polymerizable functional groups per one inorganic particle is reduced, so that even when copolymerized with the polymerizable monomer, a three-dimensional network structure is formed. As a result, it is soluble in an organic solvent and has melt fluidity, Molding such as extrusion molding becomes easy.

The modification ratio of the water-soluble group to the hydroxyl group of the polymerizable functional group-modified inorganic particles is preferably 1 to 99%, more preferably 5 to 80%. If it is less than 1%, crosslinking becomes insufficient, mechanical strength becomes small, and transparency also deteriorates. On the other hand, when the content exceeds 99%, gelation results in insufficient thermoplasticity.

The content of the polymerizable functional group-modified inorganic particles in the thermoplastic organic-inorganic hybrid material of the present invention is preferably 1 to 80% by weight, more preferably 3 to 70% by weight. When the content of the polymerizable functional group-modified inorganic particles is less than 1% by weight, the effect of improving heat resistance and hardness is small, and when the content is more than 80% by weight, moldability is deteriorated.

In order to obtain a thermoplastic organic-inorganic hybrid material having excellent thermoplasticity and good moldability, it is preferable that the modifier ratio of the modifying group to the hydroxyl group of the polymerizable functional group-modified inorganic particles and the modifying group of the polymerizable functional group- And the content of the water-insoluble polymer. According to the test results of the present inventors, when the modifying ratio of the modifying group to the hydroxyl group of the polymerizable functional group-modified inorganic particles is 1 to 30%, the content of the polymerizable functional group-modified inorganic particles is preferably 1 to 80% When the modification ratio of the water-soluble group to the hydroxyl group of the polymerizable functional group-modified inorganic particles is 30 to 50%, the content of the polymerizable functional group-modified inorganic particles is preferably 1 to 30% by weight, , The content of the polymerizable functional group-modified inorganic particles is preferably in the range of 1 to 10% by weight.

The inorganic particles are not particularly limited as long as they have a hydroxyl group on their surface. In this case, a water-soluble group having a polymerizable functional group can be bonded to the hydroxyl group on the surface of the inorganic particle via a covalent bond. Examples thereof include silica particles, alumina particles, titania particles, zirconia particles, and the like. Among these, silica particles are preferable because they are easy to obtain and fine particles can be easily obtained. Even more preferred are colloidal silica particles which are very fine particles. Such colloidal silica can be easily synthesized from a sol-gel method or water glass using alkoxysilane as a raw material. In addition, it is also possible to use polysilicic acid hydrolyzed by an acid such as sodium silicate or water glass.

The particle diameter of the silica particles is preferably 1 to 100 nm, more preferably 1 to 50 nm. When the silica particles are 100 nm or less, the organic phase and the inorganic phase are very finely dispersed, and a very homogeneous material can be obtained. Colloidal silica particles having such a particle diameter are commercially available and can be easily obtained.

The group having a polymerizable functional group is not particularly limited as long as it is a group capable of forming a covalent bond to the hydroxyl group on the surface of the inorganic particle. As the compound capable of introducing such a group, there can be used acid halides, isocyanates, epoxies and thiol groups having polymerizable functional groups, and various silane coupling agents having polymerizable functional groups. Such compounds include, for example, (meth) acrylic acid halides, methacryloxypropyltrimethoxysilane, methacryloxypropyltriethoxysilane, methacryloxypropylmethyldimethoxysilane, methacryloxypropyldimethylmethoxy Silane, methacryloxypropylmethyldiethoxysilane, methacryloxypropyldimethylethoxysilane, 2-methacryloyloxyethyl isocyanate, glycidyl methacrylate, aryl glycidyl ether, bisphenol Acryloyloxyethyl isocyanate, 3-mercaptopropyl methacrylate, 3-mercaptopropyl acrylate, and the like can be given. It can be said that the polymerizable water-soluble group is covalently bonded to the inorganic particle surface by silanol, ester, ether, urethane bond or the like. Such a polymerizable functional group-modified inorganic particle can be easily obtained by reacting the above-mentioned compound having an inorganic particle with a polymerizable functional group.

Hydrophobicity may be imparted by modifying a part of the surface hydroxyl group of the inorganic oxide. Examples of the compound imparting hydrophobicity include trialkylalkoxides such as trimethylsilyl methoxide, triethylsilylmethoxide, triethylsilylmethoxide, triethylsilylethoxide, triphenylsilylmethoxide, and triphenylsilylethoxide; , Trialkylsilyl halides such as trimethylsilyl chloride, triethylsilyl chloride, and triphenylsilyl chloride. These hydrophobicity-imparting compounds may be prepared by reacting an inorganic particle with a hydroxyl group of a part of the surface of the inorganic particle before the reaction with a compound having a polymerizable functional group, or reacting the inorganic particle surface with a compound having a polymerizable functional group Lt; / RTI > of the hydroxyl group of the compound.

The polymerizable water-soluble group may have any one of a (meth) acrylic group and a vinyl group, and the polymerizable monomer may have any one of a (meth) acrylic group and a vinyl group. Here, the (meth) acrylic group is a concept including both an acryl group and a methacryl group. In this case, copolymerization can be easily conducted by using a polymerization initiator.

Specific examples of such polymerizable monomers include alicyclic structure-containing (meth) acrylates such as isobornyl (meth) acrylate, vinyl (meth) acrylate, tricyclodecanyl (meth) acrylate and dicyclopentanyl Acrylate, benzyl (meth) acrylate, 4-butylcyclohexyl (meth) acrylate, acryloylsulfone and the like. In addition, methyl (meth) acrylate, ethyl (meth) acrylate,

Propyl (meth) acrylate,

Isopropyl (meth) acrylate, butyl (meth) acrylate,

Amyl (meth) acrylate, isobutyl (meth) acrylate,

t-butyl (meth) acrylate, pentyl (meth) acrylate,

Isoamyl (meth) acrylate, hexyl (meth) acrylate,

Heptyl (meth) acrylate, octyl (meth) acrylate,

Isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate,

Nonyl (meth) acrylate, decyl (meth) acrylate,

Acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate,

Dodecyl (meth) acrylate, lauryl (meth) acrylate,

Stearyl (meth) acrylate, isostearyl (meth) acrylate,

Tetrahydrofurfuryl (meth) acrylate, butoxyethyl (meth) acrylate,

Ethoxy diethylene glycol (meth) acrylate, benzyl (meth) acrylate,

Phenoxyethyl (meth) acrylate, polyethylene glycol mono (meth) acrylate,

Polypropylene glycol mono (meth) acrylate,

Methoxyethylene glycol (meth) acrylate, ethoxyethyl (meth) acrylate,

Methoxypolyethylene glycol (meth) acrylate,

Methoxypolypropylene glycol (meth) acrylate,

2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate,

2-hydroxy-3-phenoxypropyl (meth) acrylate,

Glycidyl (meth) acrylate, polyester (meth) acrylate,

2,2,2-trifluoroethyl (meth) acrylate,

2,2,3,3-tetrafluoropropyl (meth) acrylate,

1H, 1H, 5H-octafluoropentyl (meth) acrylate,

2- (perfluorobutyl) ethyl (meth) acrylate,

2- (perfluorohexyl) ethyl (meth) acrylate,

2,2,3,3,3-pentafluoropropyl (meth) acrylate,

3- (perfluorobutyl) -2-hydroxyethyl (meth) acrylate,

3- (perfluorobutyl) -2-hydroxypropyl (meth) acrylate,

Diacetone (meth) acrylamide, isobutoxymethyl (meth) acrylamide,

N, N-dimethyl (meth) acrylamide, t-octyl (meth) acrylamide,

Dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate,

7-amino-3,7-dimethyloctyl (meth) acrylate,

N, N-diethyl (meth) acrylamide,

N, N-dimethylaminopropyl (meth) acrylamide, hydroxybutyl vinyl ether,

Lauryl vinyl ether, cetyl vinyl ether, 2-ethylhexyl vinyl ether, and the like.

Examples of the polymerizable group having a vinyl group include a styrene group and an alkylstyrene group. Examples of the polymerizable monomer having a vinyl group include styrene, p-methylstyrene, p-hydroxystyrene, ( Methacrylonitrile, acrylamide, vinyl chloride, vinyl acetate, maleic anhydride, and the like.

Further, the polymerizable monomer may be composed of a plurality of kinds of polymerizable monomers, and these polymerizable monomers may be copolymerized. By copolymerizing a plurality of kinds of polymerizable monomers, it is possible to change the properties of the copolymerized part in various ways, and it is possible to make a variety of thermoplastic organic-inorganic hybrid materials. The copolymerization of plural kinds of polymerizable monomers may be random copolymerization or block copolymerization. In both copolymers, it is possible to take a core-shell structure composed of a resin layer in which the inorganic particles become nuclei (core) and the polymer layer grows so as to surround the inorganic particles.

The thermoplastic organic-inorganic hybrid material of the present invention can be produced as follows. That is, the method for producing a thermoplastic organic-inorganic hybrid material of the present invention comprises a surface modification step of forming a polymerizable functional group-modified inorganic particle by covalently bonding a hydroxyl group having a polymerizable functional group to a part of hydroxyl groups on the surface of an inorganic particle, And a copolymerization step of copolymerizing the functional group-modified inorganic particles and the polymerizable monomer as the thermoplastic polymer by polymerization.

The polymerization method in the copolymerization step is not particularly limited, and besides solution polymerization, methods such as suspension polymerization and bulk polymerization can be used. Further, in the plural-species copolymerization step, a plurality of kinds of polymerizable monomers may be mixed at once to form a random copolymer, or a plurality of kinds of polymerizable monomers may be sequentially added one by one to form a block copolymer.

In the copolymerization step, a method in which a plurality of kinds of polymerizable monomers are mixed at one time to form a random copolymer, or a method in which a plurality of kinds of polymerizable monomers are sequentially added one by one to form a block copolymer, It is easy to form a thermoplastic organic-inorganic hybrid material having a high thermal conductivity and is a preferable method.

Particularly, a method of sequentially adding a plurality of kinds of polymerizable monomers one by one to form a block copolymer is a method in which a resin layer in which inorganic particles are nuclei (cores) Shell structure, and is a preferred method for synthesizing a functional organic-inorganic hybrid material having various properties of a polymer obtained from each polymerizable monomer. Specifically, for example, by controlling the elastic modulus by block copolymerization of a polymerizable monomer having rubber properties such as an acrylic monomer, or by polymerizing a polymerizable monomer having water repellency or hydrophilicity near the surface layer, the water repellency of the thermoplastic organic-inorganic hybrid material Or hydrophilic property can be effectively imparted. Therefore, when a plurality of kinds of polymerizable monomers are used as block copolymers, a wide variety of high-performance materials having desired characteristics can be designed.

Hereinafter, embodiments of the present invention will be described in detail.

PMMA-silica hybrid material

<Surface Modification Process>

In a three-necked flask, methyl ethyl ketone dispersion colloidal silica (MEK-ST particle diameter 10 to 15 nm, silica content 30% by weight, manufactured by Nissan Chemical Industries Ltd.) and 2- (methachlorooxy) ethyl isocyanate (Hereinafter referred to as &quot; MOI &quot;) was added at various ratios, and about 650 ppm of di-n-butyltin dilaurate (hereinafter referred to as DBTDL) as a catalyst was added to the weight of the colloidal silica, Day to obtain MOI modified colloidal silica.

<Copolymerization Step>

A thermometer, a cooling tube and a stirring blade were attached to a four-necked flask. After the inside of the flask was purged with nitrogen, methyl ethyl ketone, benzoyl peroxide and MOI modified colloidal silica were added, and the flask was heated in an oil bath to 80 DEG C , And methyl methacrylate was added dropwise over 15 minutes while stirring at a rate of about 120 rpm. After completion of the dropwise addition, the mixture was further stirred for 6 hours. The injection amount was methyl methacrylate: methyl ethyl ketone = 1: 1.25 (weight ratio), and benzoyl peroxide was adjusted to 0.4 mol% with respect to methyl methacrylate. After completion of the stirring, the reaction solution was added dropwise to methanol of 20 times, and a white solid was collected by reprecipitation method, followed by vacuum drying at room temperature for 24 hours to obtain a PMMA-silica hybrid material.

 <Evaluation>

The PMMA-silica hybrid material obtained as described above was subjected to a solubility test in an organic solvent. In the dissolution test, 1.0 g of the PMMA-silica hybrid material was weighed into a sample bottle, and an organic solvent (methyl ethyl ketone (MEK), tetrahydrofuran (THF), acetone, N, N- dimethylacetamide (DMAc) Chloromethane) was added and stirred at room temperature, and the solubility in an organic solvent was observed.

Moldability (thermoplasticity) was evaluated by preheating the PMMA-silica hybrid material at 120 to 130 占 폚 for 10 minutes by using a hot press apparatus and pressing it at 190 占 폚 under a pressure of 10 MPa to produce a film Respectively.

In addition, the measurement sample (film) was dissolved in methyl ethyl ketone and then cast by casting to measure various properties such as heat resistance, moldability, elongation, tensile strength, Young's modulus, transmittance and surface hardness. A measurement sample was prepared as follows. That is, the PMMA-silica hybrid material synthesized as described above was added to methyl ethyl ketone in an amount of 10% by weight, and the mixture was immersed in a water bath temperature of about 60 ° C and a dissolution time of 30 minutes using an ultrasonic cleaner (SH- 90 min. &Lt; / RTI &gt; This solution was cast on a PET sheet and dried in a heating oven at 40 DEG C for 4 hours. Thereafter, it was vacuum-dried at 80 DEG C for 20 hours to obtain a PMMA-silica hybrid membrane. The thus obtained PMMA-silica hybrid film was measured for heat resistance, moldability, elongation, tensile strength, Young's modulus, surface hardness and light transmittance.

The heat resistance (thermal decomposition temperature: Td) was measured by thermogravimetric analysis (TG-DTA) using TG / DTA 6300 manufactured by Seiko Instruments Inc. About 10 mg of a sample was placed in a sample plate made of aluminum, and the temperature was measured at a temperature raising rate of 10 占 폚 / min and a temperature range of 25 占 폚 to 500 占 폚 in a nitrogen stream (flow rate: 200 ml / min). From the obtained TG curve, the thermal decomposition temperature was calculated by extrapolation.

The tensile strength was measured using a table-top tensile tester RITOLSENSTA LSC-05/30 manufactured by JT TOCi Co., Ltd. The measurement sample was prepared by inserting a PMMA-silica hybrid film cut into a short shape having a width of about 1 cm and a length of about 3 cm into a base paper for tensile strength measurement. The measurement was performed at a chuck distance of 20 mm and a tensile speed of 5 mm / min. The Young's modulus was determined from the initial gradient of tensile strength, elongation and stress-strain curve at the time of fracture of each sample. Each value was also determined by averaging 6 to 10 measurements. Also, at this time, the sample containing an error of 5% or more and the sample whose rupture position is inadequate were excluded from the average value. Regarding the film thickness and the film width required for calculation of the tensile strength, the film thickness was measured using a film thickness measuring instrument manufactured by Mitsutoyo Co., Ltd. to 0.1 mu m, and the film width was measured using Nosguis (manufactured by Mitsutoyo Co., Ltd.) Respectively. The surface hardness (pencil hardness) of the film surface was measured in accordance with JIS-K-5400 using a pencil hardness tester manufactured by Imoto Co., Ltd.

The light transmittance was measured using a V-530 spectrophotometer manufactured by JASCO Corporation. The measurement area was a wavelength range of ultraviolet-visible light (200 to 800 nm). A film having a thickness of about 80 to 120 占 퐉 cut into 30 mm 占 10 mm was sandwiched between sample holders for spectrophotometers and the light transmittance per 1 nm was measured.

(result)

&Lt; Solubility in Organic Solvent and Moldability (Thermoplastic)

The results are shown in Table 1. From this table, it can be seen that the higher the modifying ratio based on the MOI of the hydroxyl group on the silica surface, the easier the gelation and the lower the solubility and the moldability (thermoplasticity) for the organic solvent. Further, it can be seen that the higher the content of the MOI-modified silica is, the easier the gelation is, and the solubility in an organic solvent and the moldability (thermoplasticity) are lowered.

It is known that there is a correlation between thermoplasticity and solubility, and that the better the solubility, the better the thermoplasticity. For this reason, in order to obtain a PMMA-silica hybrid material having thermoplasticity, it is necessary to lower the modifying rate by the MOI of the hydroxyl group on the surface of the silica to less than 99%. However, when the modifying ratio by the MOI of the hydroxyl group on the surface of the silica is less than 1%, the solubility (that is, thermoplastic) is excellent, but the degree of crosslinking becomes small and the effect of hybridization such as reduction of mechanical strength and transparency is not sufficiently exhibited. For this reason, the modifying ratio of the modifying group to the hydroxyl group of the polymerizable functional group-modified inorganic particle is preferably 1 to 99%, more preferably 5 to 80%.

From the results shown in Table 1, there is also a correlation between the solubility and the MOI-modified silica content, and it is found that the more the MOT-modified silica content is, the lower the solubility. However, if the content of the MOI-modified silica is too small, the effect of improving heat resistance and surface hardness is reduced.

From the above results, in order to obtain a thermoplastic organic-inorganic hybrid material having good moldability and excellent heat resistance and hardness, it is important to consider two values of the modulus of the surface hydroxyl group on the silica and the MOI modified silica content , Based on the results of Table 1, when the modifying ratio by MOI is 1 to 5%, the content of MOI modified silica is 1 to 80% by weight, and when the modifying ratio by MOI is 5 to 15% The content of MOI modified silica is 1 to 25% by weight when the content is 1 to 60% by weight and the modifying ratio by MOI is 15 to 30%, and when the modifying ratio by MOI is 30 to 45% 1 to 15% by weight, and when the modifying ratio by MOl is 45 to 80%, the MOI modified silica content is preferably in the range of 1 to 5% by weight.

Modification ratio (mol%) by MOI of hydroxyl surface of silica 5% 15% 30% 45% 60% 80% 100%
MOI
Equation
Silica
(weight%)
5% ○ ○ ○ ○ ○ ○ × 10% ○ ○ ○ ○ × × - 15% ○ ○ ○ ○ - - - 20% ○ ○ ○ × - - - 25% ○ ○ ○ - - - - 30% ○ ○ × - - - - 60% ○ ○ - - - - - 80% ○ × - - - - - ○: dissolution / melting, ×: insoluble / non-melting (gel)

<Measurement results of heat resistance, moldability, elongation, tensile strength, Young's modulus, surface hardness and light transmittance>

As shown in Table 2, PMMA-silica hybrid materials having various MOI moduli and MOI-modified silica contents were prepared (Examples 1 to 12, Test Examples 1 to 4 and Comparative Example 1), and heat resistance, formability, elongation, Strength, Young's modulus, transmittance, and surface hardness. Similar measurements were made for PMMA.

(Moldability)

From Table 2, it can be seen that the moldability is excellent as (1) the modifier by the MOI of the hydroxyl group on the surface of silica is low, and (2) the smaller the content of MOI-modified silica is, the better the moldability. This result is consistent with the results derived from the solubility test in the organic solvent shown in Table 1 above.

(Heat resistance)

It can be seen that the thermal decomposition temperature (Td value) is higher as (1) Td value is higher as the modifying ratio by MOI of the hydroxyl surface on the silica is higher, and (2) as the silica content is higher in the hybrid, the Td value is higher. It can be seen that the heat resistance can be increased by the copolymerization of silica. This is believed to be due to the formation of strong intermolecular crosslinking via silica by MOI-modified silica, and by the formation of hydrogen bonds due to MOI sites, the mobility of the polymer chain was strongly suppressed.

(Transmittance)

As to the transmittance, it was confirmed that the transmittance was almost the same as that of PMMA, the silica particles were well dispersed in the polymer, and the PMMA-specific high transparency was maintained.

(Young's modulus)

1) Relationship with silica content

The Young's modulus increased with increasing MOI modifier silica content. Since the PMMA-silica is covalently bonded, the mobility of the polymer chain is strongly bound and thus the Young's modulus is considerably increased.

2) Relationship with MOI formula rate

As the MOI moderation rate increased, it was found that it increased remarkably. This is believed to be due to the increase in cross-linking between the PMMA-silica as the MOI modulus increases, resulting in more motion of the polymer.

From the above results, it can be seen that as for the MOI modifier ratio, the lower the moldability is, the higher the moldability is, and the higher the Td value, the better the heat resistance and the higher the Young's modulus. For this reason, in order to obtain a PMMA-silica hybrid material having excellent moldability, excellent heat resistance and Young's modulus, it is preferable that the MOI modifying ratio is not excessively large or small and preferably 1 to 99%, more preferably 5 to 80% . In addition, it can be seen that the content of MOI-modified silica also affects the moldability, heat resistance and Young's modulus. In other words, in order to obtain a thermoplastic organic-inorganic hybrid material having good moldability and excellent heat resistance and surface hardness, it is important to consider two values, namely, the modulus of the surface hydroxyl group on the silica surface and the MOI modified silica content, In the case where the modifying ratio by MOI is 1 to 5%, the content of MOI modified silica is 1 to 80% by weight, the content of MOI modified silica is 1 to 60% by weight when the modifying ratio by MOI is 5 to 15% In the case where the modifying ratio by MOI is 1 to 25% by weight and the modifying ratio by MOI is 30 to 45% when the modifying ratio by MOI is 15 to 30%, the content of MOI modified silica is 1 to 15% by weight, Is 45 to 80%, it is understood that the content of the MOI modified silica is preferably in the range of 1 to 5% by weight.

(MMA-methyl acrylate) random copolymer-silica hybrid material

As a polymerizable monomer, a (MMA-MA) random copolymer-silica hybrid material was synthesized using two kinds of compounds, MMA and methyl acrylate. Details of the synthesis method are shown below.

<Surface Modification Process>

The MOI modified colloidal silica was obtained in the same manner as in the case of the above-mentioned PMMA-silica hybrid material.

<Random Copolymerization Step>

A thermometer, a cooling tube, and a stirrer were attached to a four-necked flask, and the inside of the flask was purged with nitrogen. Then, 1.25 times (by weight) methyl ethyl ketone of the monomer mixture described later was mixed with 0.4 mol% of benzoyl peroxide , A predetermined amount of MOI modified colloidal silica was added. Then, the mixture was heated to 80 DEG C in an oil bath, and a mixture (monomer mixture) of methyl methacrylate and methyl acrylate in a predetermined mixing ratio (monomer mixture) was added dropwise over a period of 15 minutes while stirring at a rate of about 120 rpm. And reacted for 6 hours. After completion of the reaction, the reaction solution was added dropwise to methanol in an amount of 20 times, and the polymer was collected by reprecipitation. Vacuum drying was conducted at room temperature for 24 hours to obtain a random copolymer (MMA-MA) of Examples 13 to 18 -Silica hybrid material was obtained in a yield of 60 to 80%.

(evaluation)

The thus obtained (MMA-MA) random copolymer-silica hybrid material was evaluated for heat resistance, moldability, elongation, tensile strength, Young's modulus, transmittance, surface And hardness were measured. The results are shown in Table 3. As can be seen from this table, it can be seen that even when random copolymerization is carried out by mixing MMA and methyl acrylate as polymerizable monomers, it is a hybrid material having excellent moldability, excellent heat resistance and Young's modulus.

(MMA-ethyl acrylate) random copolymer-silica hybrid material

(MMA-EA) random copolymer-silica hybrid materials of Examples 19 to 21 were synthesized by using two kinds of compounds of MMA and ethyl acrylate as polymerizable monomers. The synthesis method is the same as that in the case of the (MMA-MA) random copolymer-silica hybrid material except that ethyl acrylate is used in place of methyl acrylate, and a description thereof will be omitted.

(evaluation)

The thus obtained (MMA-ethyl acrylate) random copolymer-silica hybrid material was evaluated for heat resistance, moldability, elongation, tensile strength, Young's modulus and transmittance by the same method as the evaluation method for the PMMA- , Surface hardness, etc. were measured. The results are shown in Table 4. As can be seen from this table, it can be seen that even when random copolymerization is carried out by mixing MMA and ethyl acrylate as polymerizable monomers, the resultant hybrid material is excellent in moldability, heat resistance and Young's modulus.

(MMA-butyl acrylate) random copolymer-silica hybrid material

The (MMA-BA) random copolymer-silica hybrid materials of Examples 22 to 24 were synthesized by using two kinds of compounds of MMA and butyl acrylate as polymerizable monomers. The synthesis method is the same as that in the case of the (MMA-methyl acrylate) random copolymer-silica hybrid material, except that butyl acrylate is used in place of methyl acrylate, and a description thereof will be omitted.

(evaluation)

The thus obtained (MMA-butyl acrylate) random copolymer-silica hybrid material was evaluated for heat resistance, moldability, elongation, tensile strength, Young's modulus and transmittance by the same method as the evaluation method of the PMMA- , Surface hardness, etc. were measured. The results are shown in Table 5. As can be seen from the table, it can be seen that even when random copolymerization is carried out by mixing MMA and butyl acrylate as polymerizable monomers, it is a hybrid material having excellent moldability, excellent heat resistance and Young's modulus.

(MMA-methyl acrylate) block copolymer-silica hybrid material

As a polymerizable monomer, a (MMA-MA) block copolymer-silica hybrid material was synthesized using a mixture of MMA and methyl acrylate. Details of the synthesis method are shown below.

<Surface Modification Process>

The MOI modified colloidal silica was obtained in the same manner as in the case of the above-mentioned PMMA-silica hybrid material.

&Lt; Block copolymerization step &

A thermometer, a cooling tube, and a stirrer were attached to a four-necked flask. After the inside of the flask was purged with nitrogen, 1.25 parts by weight (weight ratio) of the polymerizable monomer and 0.4 part by weight of benzoyl peroxide with respect to the polymerizable monomer , A predetermined amount of MOI modified colloidal silica was added. Then, a predetermined amount of methyl acrylate was added dropwise over 15 minutes while being heated to 80 DEG C in an oil bath and stirred at a speed of about 120 rpm, and the mixture was reacted for 1 hour after completion of dropwise addition. After completion of the reaction, the MMA monomer was further added dropwise over 15 minutes, and the mixture was reacted for 6 hours after completion of dropwise addition. The reaction solution was dripped into 20-fold amount of methanol, and the polymer was collected by reprecipitation. Vacuum drying was conducted at room temperature for 24 hours to obtain a (MMA-MA) block copolymer-silica hybrid material of Examples 25 to 29 Was obtained in a yield of 60 to 80%.

(evaluation)

The thus obtained (MMA-MA) block copolymer-silica hybrid material was evaluated for heat resistance, moldability, elongation, tensile strength, Young's modulus, transmittance, surface And hardness were measured. The results are shown in Table 6. As can be seen from this table, it can be seen that even if MMA and methyl acrylate are mixed as a polymerizable monomer and block copolymerization is performed, the resultant material is a hybrid material having excellent moldability, excellent heat resistance and Young's modulus.

(MMA-ethyl acrylate) block copolymer-silica hybrid material

(MMA-EA) block copolymer-silica hybrid materials of Examples 30 to 32 were synthesized by using two kinds of compounds as MMA and ethyl acrylate as polymerizable monomers. The synthesis method is the same as that in the case of the (MMA-methyl acrylate) block copolymer-silica hybrid material, except that ethyl acrylate is used in place of methyl acrylate, and a description thereof will be omitted.

(evaluation)

The thus obtained (MMA-EA) block copolymer-silica hybrid material was evaluated for heat resistance, moldability, elongation, tensile strength, Young's modulus, transmittance, surface And hardness were measured. The results are shown in Table 7. As can be seen from this table, it can be seen that even if MMA and ethyl acrylate are mixed as a polymerizable monomer and block copolymerization is performed, the resultant material is a hybrid material having excellent moldability, excellent heat resistance and Young's modulus.

The present invention is not limited in any way by the description of the embodiments of the present invention. Various modifications are also included in the present invention without departing from the scope of the claims, and various modifications can be made within the scope of the present invention.

The thermoplastic organic-inorganic hybrid material of the present invention is a functional material excellent in heat resistance and transparency, and further excellent in moldability, and can be used in various industrial fields.

Claims (12)

A thermoplastic organic-inorganic hybrid material comprising a polymerizable functional group-modified colloidal silica particle in which a water-soluble group having an acrylic polymerizable functional group is covalently bonded to the hydroxyl group on the surface of the colloidal silica particle and an acrylic polymerizable monomer as a thermoplastic polymer by polymerization as, The polymerizable functional group-modified colloidal silica particles are formed by covalently bonding a water-soluble group having an acrylic polymerizable functional group to a part of the hydroxyl groups on the surface of the colloidal silica particles and leaving an unreacted hydroxyl group, When the modifying ratio of the polymerizable functional group-modified colloidal silica particles to the hydroxyl group is less than 1 to 30%, the content of the polymerizable functional group-modified colloidal silica particles is 1 to 80% by weight, When the modifying ratio is less than 30 to 50%, the content is 1 to 30% by weight, When the modifying ratio is 50 to 80%, the content is 1 to 10% by weight, Wherein the thermoplastic organic-inorganic hybrid material is soluble in an organic solvent and has melt fluidity. delete delete delete delete delete The thermoplastic organic-inorganic hybrid material according to claim 1, wherein the silica particles have a particle diameter of 1 to 100 nm. delete delete delete A surface modification step of forming a polymerizable functional group-modified colloidal silica particle by covalently bonding a hydroxyl group having an acrylic polymerizable functional group only to a part of the hydroxyl groups on the surface of the colloidal silica particle and leaving an unreacted hydroxyl group; And And a copolymerization step of copolymerizing the polymerizable functional group-modified colloidal silica particles and an acrylic polymerizable monomer which becomes a thermoplastic polymer by polymerization,  When the modifying ratio of the modifying group to the hydroxyl group of the polymerizable functional group-modified colloidal silica particles obtained in the surface modification step is less than 1 to 30%, the total amount of the thermoplastic organic-inorganic hybrid material The copolymerization step is carried out at a content of 1 to 80% by weight of the silica particles, and when the modifying ratio is less than 30 to 50%, the copolymerization step is carried out at a content of 1 to 30% by weight, When the ratio is 50 to 80%, the copolymerization step is carried out with the content of 1 to 10% by weight, Wherein the organic-inorganic hybrid material obtained by the surface modification step and the copolymerization step is soluble in an organic solvent and has melt fluidity. The method for producing a thermoplastic organic-inorganic hybrid material according to claim 11, wherein in the copolymerization step, a plurality of kinds of acrylic polymerizable monomers are sequentially added one by one to form a block copolymer.