KR101189186B1 - Polymer-Organic Nano-Fiber Composite Having Superior Thermal Expansion Property and Light-Transmission and Transparent Composite Film - Google Patents

Abstract

The present invention relates to a polymer-organic nanofiber composite having excellent thermal expansion properties and light transmittance, including a polymer resin binder and organic nanofibers, and a light-transmitting composite film using the same. According to the present invention, there is provided a polymer-organic nanofiber composite comprising a curable polymer resin and an organic nanofiber having a fiber diameter of 20 nm to 20 μm, and a light-transmissive composite film formed therefrom. The polymer-organic nanofiber composite according to the present invention and the light-transmissive composite film formed therefrom have excellent thermal expansion properties, specifically, excellent thermal expansion coefficient and light transmittance smaller than 15 to 20 ppm / ° C., and the composite film formed from the composite according to the present invention It has excellent thermal expansion properties and light transmittance, and is used in electrical, electronic, semiconductor, optical and display materials, specifically, next-generation semiconductor substrates, PCBs, package packaging, OTFTs, flexible display substrates, transparent plates, optical lenses, plastic substrates for liquid crystal display devices, It is suitable for use as a substrate for color filters, plastic substrates for organic EL display elements, solar cell substrates, touch panels, light guide plates, optical elements, light guide paths, and LED encapsulants.

Description

Polymer-organic nanofiber composite having excellent thermal expansion properties and light transmittance, and light-transmitting composite film using the same {Polymer-Organic Nano-Fiber Composite Having Superior Thermal Expansion Property and Light-Transmission and Transparent Composite Film}

The present invention relates to a polymer-organic nanofiber composite having excellent thermal expansion properties and light transmittance including a polymer binder and organic nanofibers, and a light-transmitting composite film (sheet) using the same.

Polymeric materials are excellent in physical properties such as light weight, moldability, non-destructiveness, design, processability, etc., and are of interest as substitutes for substrate materials such as, for example, glass substrates. Therefore, such a polymer material requires a combination of excellent thermal expansion properties, thermal stability (dimension stability), light transmittance, optical properties, surface flatness, chemical resistance, and the like, which are conventionally used as a substrate material.

On the other hand, polymer materials are generally processed together with inorganic materials or metal materials during processing to devices used in the fields of electricity, electronics, semiconductors, optics and displays. However, the thermal expansion coefficient of a polymer material, for example, an epoxy resin, is approximately 50 to 80 ppm / ° C., and the thermal expansion coefficient of a ceramic material and a metal material that are inorganic particles (for example, the thermal expansion coefficient of silicon is 3 to 5 ppm / ° C.). The coefficient of thermal expansion of copper is 17 ppm / ° C.), and the coefficient of thermal expansion (CTE) is very large, several to several tens of times.

Therefore, during the process, the physical properties and processability of the polymer material are significantly limited due to the different coefficients of thermal expansion of the polymer material and the inorganic material or the metal material. In addition, for example, an undercoat layer, an inorganic barrier layer, and an overcoat layer are laminated on both sides of a bare film which is a transparent optical film or a semiconductor packaging in which a silicon wafer and a polymer substrate are used adjacent to each other. In the case of a plastic substrate, the thermal expansion coefficient difference between the interlayer materials (polymers and inorganic materials) is large, and thus, the difference in the coefficient of thermal expansion (CTE-mismatch) between the components during the process / use temperature change, such as heating / cooling. Due to the thermal stress (thermal stress) occurs at the interface, resulting in product defects such as crack generation, interfacial peeling, bending of the substrate, peeling-off of the coating layer, breaking the substrate.

As such, due to the CTE of a very high polymer material compared to the metal / ceramic material, it is difficult to design and processability / reliability of next-generation parts and substrates that require high integration, high micronization, flexibility, and high performance. In other words, due to the high thermal expansion properties of the polymer material at the part process temperature, not only defects occur in manufacturing the part, but also the process is limited and the design of the part and securing processability and reliability are problematic. Therefore, improved thermal expansion properties of the polymer material, that is, suppression of dimensional change, are required to secure processability and reliability of electronic components.

In order to improve the thermal expansion properties of polymer materials (i.e., suppress the dimensional change), in general, (1) a new polymer synthesis method is used to design a new polymer resin with reduced CTE or (2) inorganic resin (inorganic filler) ) And / or composites with fibers or fabrics have been used.

When the polymer resin and the inorganic filler (inorganic particles) are combined to improve the thermal expansion characteristics of the double polymer resin, a large amount of the inorganic filler having a size of about 2 to 30 μm, for example, 80-90 wt% of the total weight of the composite It can be used only to see the effect of reducing CTE up to the level of 15 ppm / ℃. However, a high filling of the filler is accompanied by a problem that the workability and the physical properties of the part is lowered. That is, the decrease in fluidity due to the large amount of filler and the formation of voids when filling the narrow space is problematic. In addition, the addition of fillers increases the viscosity of the material exponentially. Furthermore, the size of the filler tends to decrease due to the miniaturization of the semiconductor structure, but the problem of fluidity deterioration (increase in viscosity) becomes even more serious when the filler of 1 µm or less is used. On the other hand, when a filler having a large average particle size is used, the frequency at which the composite of the resin and the filler is not filled in the applied site is increased. In addition, the light transmittance of the composite is damaged due to the difference in refractive index between the organic polymer resin and the inorganic filler and the inorganic filler contained in a large amount, and thus, it is not suitable for use as an optical material requiring light transmission.

On the other hand, light transmittance in the composite system depends on the size of the filler (inorganic material, fiber, etc.), refractive index, filler content, film thickness, wavelength, and the like in the composite.

[Equation 1]

(Wherein, I .: incident light intensity, I: intensity of transmitted light, n _m: If the matrix (polymer composite: the refractive index of the filler, r:: refractive index, n _p of the polymer), the diameter of the filler, χ: thickness of the film, φ: content of additive (filler), wavelength of incident light)

Therefore, in order to secure the light transmittance of the conventional resin-glass fiber composite, a method of controlling the refractive index difference between the resin of the matrix and the glass fiber filler to 0.002 or less has been proposed. However, this method is difficult to select a polymer resin having a low refractive index difference of 0.002 level with the glass fiber in the entire visible wavelength range, it is difficult to manufacture a film with excellent optical properties, or to increase the manufacturing cost to maintain light transmittance There is no difficulty. In other words, when using low-cost E-glass type high refractive glass fibers, a resin having a relatively high refractive index should be used for refractive index matching. There is a difficult problem. In addition, when using a glass fiber having a low refractive index in order to solve this problem, there is a problem that the manufacturing cost of the composite film is increased due to the use of expensive glass fibers.

As can be seen in Equation 1, another method for producing a light-transmitting fiber composite is a method for producing a fiber composite using nano-grade fibers, but the resin and fiber composites currently commonly used are optical Light transmittance suitable for use as a material is not secured.

Therefore, according to the requirements of this technical field, such as next-generation semiconductor substrate, printed circuit board (PCB), packaging, organic thin film transistor (OTFT), flexible display substrate (electrical, electronic, There is a need for polymer composites and composite films (sheets) having thermal expansion properties and light transmittance suitable for use in semiconductor, optical and display materials.

According to one aspect of the invention, there is provided a polymer-organic nanofiber composite excellent in thermal expansion properties and light transmittance.

According to another aspect of the present invention, there is provided a composite film (sheet) having excellent thermal expansion properties and light transmittance formed from the polymer-organic nanofiber composite according to the present invention.

According to one aspect of the invention,

A polymer-organic nanofiber composite is provided that includes a curable polymer resin binder and organic nanofibers having a fiber diameter of 20 μm or less.

According to another aspect of the present invention,

The light-transmissive composite film (sheet) formed of the polymer-organic nanofiber composite according to the present invention is provided.

The polymer-organic nanofiber composite provided by the embodiment of the present invention and the light-transmissive composite film formed therefrom have excellent thermal expansion properties, specifically, 15 to 20 ppm / ° C. or less of Coefficient of Thermal Extension and light transmittance. In addition, the nano-organic fibers used in the composite of the present invention can not only easily adjust the thickness of the organic fibers to the nano-class by melt spinning, and because of this, polymer-organic nanofibers having excellent light transmittance regardless of the refractive index of the resin binder Composites and composite films are obtained. On the other hand, since the composite comprising the organic nanofibers according to the present invention does not generate entanglement of the inorganic filler generated during the production of the composite including the conventional powdery inorganic filler, workability into the composite and the composite film (sheet) is improved. Furthermore, compared with the case where the inorganic filler is blended at the same amount of nanoorganic fiber blending as the conventional inorganic filler, it shows more improved thermal expansion characteristics.

The composite according to the present invention may be in the form of a composite film (sheet), which has excellent thermal expansion properties and light transmittance, and may include electrical, electronic, semiconductor, optical and display materials, specifically, next-generation semiconductor substrates, printed circuit boards (PCBs), Packaging, Organic Thin Film Transistor (OTFT), Flexible Display Substrate, Transparent Plate, Optical Lens, Plastic Substrate for Liquid Crystal Display, Color Filter Substrate, Plastic Substrate for Organic EL Display, Solar It is suitable for use in battery substrates, touch panels, light guide plates, optical elements, light guide paths, and LED encapsulants.

1 is a photograph showing a light-transmissive composite film obtained in Example 1. FIG.

As described above, the present invention has been proposed to improve thermal expansion properties and light transmittance of a polymer composite used as a conventional electric, electronic, semiconductor, optical and display material, and the polymer-organic nanofiber composite according to the present invention is organic nano It is characterized by including a fiber. According to the present invention there is also provided a light-transmitting polymer-organic nanofiber composite film (sheet) formed from the polymer-organic fiber composite according to the present invention.

Polymer-organic nanofiber composites and composite films according to the present invention are excellent in thermal expansion properties, dimensional stability, light transmittance and surface flatness, and instead of conventional glass substrates, electrical, electronic, semiconductor, optical and display materials, more specifically, next generation semiconductor substrates. Printed Circuit Board (PCB), Packaging, Organic Thin Film Transistor (OTFT), Flexible Display Substrate, Transparent Plate, Optical Lens, Plastic Substrate for Liquid Crystal Display, Substrate for Color Filter, Organic It is suitable for use as a plastic substrate for an EL display element, a solar cell substrate, a touch panel, a light guide plate, an optical element, a light guide path, and an LED encapsulant.

The use of such electrical, electronic, semiconductor, optical and display materials requires not only good thermal expansion properties (i.e. low CTE), but also light transmission, especially for use as optical and display materials. Accordingly, the present invention provides a polymer-organic nanofiber composite which can be prepared as a composite sheet having excellent light transmittance and surface flatness as well as excellent thermal expansion properties such as heat stability and dimensional stability.

The polymer-organic nanofiber composite according to the present invention includes a polymer resin binder and organic nanofibers. The polymer-organic nanofiber composite according to the present invention is characterized in that it exhibits improved thermal expansion properties and light transmittance due to the inclusion of organic nanofibers, and the polymer resin binder is a conventional electric, electronic, semiconductor, optical and / or display material. Any polymer resin binder known to be used in the organic-inorganic composite for solvents may be used, and the polymer resin binder is not particularly limited. Specifically, as the polymer resin binder, a photocurable polymer resin binder or a thermosetting polymer resin binder may be used.

Photocurable polymeric resin binders are generally photocurable oligomers, photocurable monomers, photoinitiators and any additives added as needed (e.g. inhibitors, bleing agents, antifoams, stabilizers, antioxidants, ultraviolet absorbers, adhesion promoters, Pigments, inorganic fillers, and the like). The polymer-organic nanofiber composite according to the present invention may be used a photocurable polymer resin binder including any kind of photocurable oligomer, photocurable monomer, photoinitiator and any other additives known in the art.

Examples of the photocurable oligomers that can be used in the photocurable polymer resin binder include, but are not limited to, epoxy acrylates, urethane acrylates, polyester acrylates, acrylic acrylates, polybutadiene acrylates, silicone acrylics. Elates, melamine acrylates, dendritic acrylates, cycloaliphatic epoxy (hydrogenated epoxy), aromatic epoxys (specifically bisphenol A epoxy, bisphenol F epoxy), aliphatic cyclic epoxy Aliphatic cyclic epoxy (specifically dicyclo pentadiene type epoxy) and oxetane are mentioned. These may be used alone or in combination of two or more.

Examples of the photocurable monomer that can be used in the photocurable polymer binder include, but are not limited to, (meth) acrylate monomers having mono-, di-, tri- or higher functionality. More specifically, the (meth) acrylate monomers have one or more acrylate groups, or methacrylate groups, but are not limited to, for example, phenoxyethyl acrylate, phenoxydiethylene glycol acrylate, phenoxy Tetraethylene glycol acrylate, phenoxy hexaethylene glycol acrylate, isobornyl acrylate, isobornyl methacrylate, bisphenol ethoxylate diacrylate, ethoxylate phenol monoacrylate, polyethylene glycol 200 diacrylate, tripropylene Glycol diacrylate, trimethyl propane triacrylate, polyethylene glycol diacrylate, ethylene oxide addition type triethyl propane triacrylate, pentaerythritol tetraacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacryl Late, ethoxyl ET may be a de pentaerythritol tetra acrylate, 2-phenoxyethyl acrylate, bisphenol A diacrylate federated ethoxylates. These may be used alone or in admixture of two or more.

As radical photopolymerization initiator for acrylates, any radical photopolymerization initiator known in the art can be used, but is not limited to 2,4-bistrichloromethyl-6-p-methoxysteel-s-triazine , 2-p-methoxysteel-4,6-bistrichloromethyl-s-triazine, 2,4-trichloromethyl-6-triazine, 2,4-trichloromethyl-4-methylnaphthyl- 6-triazine, benzophenone, p- (diethylamino) benzophenone, 2,2-dichloro-4-phenoxyacetophenone, 2,2'-diethoxyacetophenone, 2,2'-dibutoxyacetophenone , 2-hydroxy-2-methylproriophenone, pt-butyltrichloroacetophenone, diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, bis (2,4,6-trimethylbenzoyl) phenyl phosph Pin oxide, 2-methyl thioxanthone, 2-isobutyl thioxanthone, 2-dodecyl thioxanthone, 2,4-dimethyl thioxanthone, 2,4-diethyl thioxanthone, and 2,2'- Bis-2-chlorophenyl And -4,5,4 ', 5'-tetraphenyl-1,2'-biimidazole compounds.

In addition, any cationic photopolymerization initiator known in the art may be used as the cationic photopolymerization initiator for epoxy resins, but is not limited thereto, iodonium salts, borate salts, triazine compounds, azo compounds, peroxides, sulfonium salts, azo Nium salt, halonium salt, more specifically diphenyl-4-thiophenoxyphenylsulfonium hexafluoroantimonate, tri-p-trisulfonium trifluoromethanesulfonate, tri-p-trisulfonium hexafluorophosphate , Triphenylsulfonium tetrafluoroborate, 4-isopropyl-4'-methyldiphenyl iodonium tetrakis (pentafluorophenyl) borate, bis (4-t-butylphenyl) iodium trifluoromethanesulfonate, bis ( 4-t-butylphenyl) iodine hexafluorophosphate, diphenyliodine hexafluorobisic acid, diphenyliodine hexafluorophosphate, diphenyliodnium triflu Ormethanesulfonic acid, benzoin, benzyl, benzoin methyl ether, benzoin isopropyl ether, acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexyl Phenylketone, 2-methyl-1- (4-methylthiophenyl) -2-morpholinolpropane-1-one, N, N-dimethylaminoacetophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2 -tert-butyl anthraquinone, 1-chloroanthraquinone, 2-amyl anthraquinone, 2-isopropyl thioxanthone, 2,4-dimethyl thioxanthone, 2,4-diethyl thioxanthone, 2,4- Examples include diisopropyl thioxanthone, acetophenone dimethyl ketal, benzophenone, 4-methylbenzophenone, 4,4'-dichlorobenzophenone, 4,4'-bisdiethylaminobenzophenone, Michler's ketone, and the like. have.

The photopolymerization initiator may be blended in an amount of 1 to 10 parts by weight per 100 parts by weight of the mixture of the photocurable oligomer and the photocurable monomer. If the amount of the initiator is less than 1 part by weight, the curing does not proceed properly or the curing rate is too slow. If the amount is more than 10 parts by weight, the curing degree is too high, the brittleness is high, or after the reaction is present as a non-reactant, there is a problem of lowering the physical properties.

Thermosetting polymeric binders are generally thermosetting resins, curing agents, optional catalysts and optional additives added as needed (e.g., inhibitors, bleing agents, antifoams, stabilizers, adhesion promoters, antioxidants, ultraviolet absorbers, pigments, inorganics). Fillers and the like). In the polymer-organic nanofiber composite according to the present invention, a thermosetting polymer binder including any kind of thermosetting resin, a curing agent, an optional catalyst, any other additives, and the like known in the art may be used.

As the thermosetting resin, any kind of thermosetting resin generally known in the art may be used, but is not limited thereto. For example,

Epoxy resins, phenol resins, polyimide resins, polyester resins, allyl ester resins, bismaleimide resins, isocyanate resins, polyphenylene ether resins, acrylic resins, melamine resins, silicone resins, benzoxadine resins, urea resins, Phenol resins, alkyd resins, furan resins, polyurethane resins, and aniline resins. These may be used independently or may use 2 or more types together.

Although it does not limit by this, For example, cresol novolak-type epoxy resin, bisphenol-A epoxy resin, bisphenol F-type epoxy resin, phenol novolak-type epoxy resin, alkylphenol novolak-type epoxy resin, biphenol F type epoxy resin, naphthalene type epoxy resin, dicyclopentadiene type epoxy resin, epoxide of condensate of phenols and aromatic aldehydes having phenolic hydroxyl groups, triglycidyl isocyanurate, alicyclic epoxy resins, copolymers thereof And the like can be used. These may be used alone or in combination of two or more.

The curing agent may also be used any kind of curing agent generally known in the art, and may be used, but not limited to, an amine curing agent, a phenol curing agent, an anhydride curing agent and the like. More specifically, as the amine curing agent, aliphatic amines, cycloaliphatic amines, aromatic amines, other amines and modified polyamines may be used, and amine compounds including two or more primary amine groups may be used. Specific examples of the amine curing agent include 4,4'-dimethylaniline (diamino diphenyl metone) (4,4'-Dimethylaniline (diamino diphenyl methone, DAM or DDM), diamino diphenyl sulfone (DDS) , at least one aromatic amine selected from the group consisting of m-phenylene diamine, diethylene triamine (DETA), diethylene tetraamine, triethylenetetraamine (triethylene tetramine, TETA), m-xylene diamine (MXDA), methane diamine (MDA), N, N'-diethylenediamine (N, N'- DEDA), tetraethylenepentaamine (TEPA), and at least one aliphatic amine selected from the group consisting of hexamethylenediamine, isophorone diamine (IPDI), N-aminoethyl pyrazine ( N-aminoethyl piperazine, AEP), Bis (4-A One or more alicyclic amines selected from the group consisting of no 3-methylcyclohexyl) methane (Bis (4-amino 3-methylcyclohexyl) methane, Larominc 260), other amines such as dicyandiamide (DICY), and polyamides And modified amines such as epoxides.

Examples of the phenol-based curing agent include, but are not limited to, phenol novolac, o-cresol novolac, phenol p- xylene resin, phenol 4,4'-dimethylbiphenylene resin, phenol dicyclopentadiene resin, and the like. Can be.

Examples of the anhydride-based curing agent include, but are not limited to, aliphatic anhydrides such as dodecenyl succinic anhydride (DDSA), poly azelaic poly anhydride, hexahydrophthalic Hexahydrophthalic anhydride, Cycloaliphatic anhydrides such as HHPA), methyl tetrahydrophthalic anhydride (MeTHPA), methylnadic anhydride (MNA), trimellitic anhydride (TMA), Aromatic anhydrides such as pyromellitic acid dianhydride (PMDA), benzophenonetetracarboxylic dianhydride (BTDA), tetrabromophthalic anhydride (TBPA), chlorendic acid And halogen-based anhydrides such as chlorendic anhydride (HET).

Catalysts may also be used, but are not limited to any type of curing agent generally known in the art, for example, dimethyl benzyl arnine (BDMA), 2,4,6-tris Tertiary amines such as (dimethylaminomethyl) phenol (2,4,6-tris (dimethylaminomethyl) phenol, DMP-30), 2-methylimidazole (2MZ), 2-ethyl-4-methyl-imidazole ( 2E4M), imidazoles such as 2-heptadecylimidazole (2HDI), and Lewis acids such as BF3-monoethyl amine (BF3-MEA) and the like.

In the thermosetting resin binder, the thermosetting resin and the curing agent are cured by the reaction of the reactive functional group of the thermosetting resin and the reactive functional group of the curing agent. Therefore, those skilled in the art can suitably adjust the content of the curing agent in the thermosetting resin binder according to the type of thermosetting resin and the curing agent used.

As the curable resin binder in the polymer-organic nanofiber composite according to the present invention, any photocurable resin binder and thermosetting resin binder generally known in the art may be used as described above. The compounding ratio of the photocurable resin binder and the thermosetting resin binder component and the molecular weight (weight average molecular weight and / or number average molecular weight) of the resin and the like are generally known in the art, and the present invention is not limited thereto. Those skilled in the art can easily make this choice.

The organic nanofibers include any polyethyleneterephthalate (PET), nylon, polyethylene naphthalate (PEN), polypropylene (PP), polyethersulfone (PES), polyvinylidene fluoride (PVDF), polyphenylene sulfide (PPS), and the like, which are generally known in the art. PEEK (polyetheretherketone), aromatic polyester, specifically, organic nanofibers made of a liquid crystalline polymer may be used.

The organic nanofibers have a fiber diameter of 20 µm or less, preferably 1 µm or less, more preferably 500 nm or less, even more preferably so that the composite exhibits sufficient light transmittance for use as an optical material and / or a display material. Things less than 300 nm can be used. If the fiber diameter exceeds 20 μm, it is not preferable in that it is difficult to secure sufficient light transmittance. The smaller the fiber diameter is, the more preferable in terms of light transmittance. However, a fiber having a diameter of 20 nm or more is difficult because it is difficult to secure processability. Preference is given to using. Therefore, nanofibers having a fiber diameter of 20 nm to 20 μm may be used.

The composite including the organic nanofibers should have a sufficiently low CTE of the composite in order to secure not only light transmittance but also sufficient thermal stability, and the organic nanofibers preferably have a coefficient of thermal expansion (CTE) of 50 ppm / ° C or less. On the other hand, the CTE of organic nanofibers is the molecular structure of the fiber, the modulus, in the case of the woven fiber, the woven state of the fiber (for example, a unidirectional fiber cross-woven form Compared to the CTE control characteristic is excellent compared to).

The organic nanofibers may be prepared using fibers having a diameter of 20 μm or less, preferably 20 nm to 20 μm by melt spinning using a polymer forming the organic nanofibers.

The fiber manufacturing method is not particularly limited, and may be produced by any method known in the art as long as the fiber is made of the above-mentioned thickness. More specifically, the organic nanofibers may be manufactured in the form of sea-island type fibers having the organic nanofibers as island components. The organic nanofibers used in the present invention are obtained by removing the sea component from such sea island yarns.

In the polymer-organic nanofiber composite, the fibers may be in the form of woven fabrics, knitted fabrics, nonwoven fabrics, unidirection multilayers, short cuts, and the like.

In the polymer-organic nanofiber composite, the amount of the polymer resin binder and the organic nanofiber may be 10/90 to 90/10 weight ratio, preferably 30/70 to 70/30 weight ratio. When the amount of the polymer resin binder is less than 10 parts by weight based on 90 parts by weight of the organic nanofibers, the amount of the polymer resin binder is small and the fibers are not effectively bound, so it is difficult to produce a composite, and the amount of the polymer resin binder is 10 parts by weight of the organic nanofibers. If the amount exceeds 90 parts by weight, the fiber content is low, and the CTE reduction effect of the polymer-organic nanofiber composite is not sufficient.

The polymer-organic nanofiber composite may be prepared by any method of preparing a composite including a polymer resin and a fiber known in the art, and the method of preparing the composite is not particularly limited. For example, when the organic nanofibers are in the form of woven fibers such as long fibers, webs, nonwoven fabrics, woven fabrics and knitted fabrics, or unidirection multilayer forms including a plurality of layers arranged in one direction, the fibers of this type may be It can be prepared into a composite by impregnation with a binder. When the organic nanofibers are in the form of short fibers, the short fibers may be dispersed in a resin binder (binder solution) to prepare a composite.

As used herein, the term "polymer-organic nanofiber polymer composite" refers to not only a polymer resin and an organic nanofiber, but also a component constituting the polymer resin binder according to the type of the polymer resin binder according to the curing form (photocurable resin binder In the case of: thermosetting monomers, photoinitiators and optional additives; in the case of thermosetting resin binders: in a broad sense including both composites before and / or after curing, including thermosetting agents, optional curing catalysts and optional additives) Used. The polymer-organic nanofiber polymer composite according to the present invention may be in the form of a cured composite film (sheet).

In the curing reaction of the polymer-organic nanofiber composite according to the present invention, any reaction conditions generally known may be used. The curing reaction conditions may vary depending on the type of polymer resin and the curing agent used, and those skilled in the art may appropriately select the curing reaction conditions according to the components of the curable polymer composite.

In another aspect of the present invention, a light-transmissive composite film formed of the polymer-organic nanofiber composite is provided, and the light-transmissive composite film may be prepared by curing the polymer-organic nanofiber composite according to the present invention.

Although not restrict | limited by this, for example, when photocuring, the cured translucent composite can be obtained by making it harden | cure for 1 to 10 minutes at the light quantity of 80-200 W / cm. For example, when thermosetting, it can harden at 50-250 degreeC for about 1 hour or more, and the hardened translucent composite can be obtained.

As shown in Equation 1, the light transmittance of the composite is related to the diameter of the filler, that is, the organic nanofibers in the present invention, and the smaller the diameter of the organic nanofibers, the higher the light transmittance. Since the polymer-organic nanofiber composite and the light-transmissive composite film (sheet) prepared according to the present invention include organic nanofibers having a diameter of 20 μm or less, excellent light transmittance is ensured. Furthermore, the polymer-organic nanofiber composite and the light-transmissive composite film (sheet) prepared therefrom exhibit excellent thermal expansion properties because the organic nanofibers having excellent CTE properties limit the thermal expansion of the polymer resin binder.

The polymer-organic nanofiber composite according to the present invention and the light-transmitting composite film (sheet) prepared therefrom have excellent thermal expansion properties, specifically 20 ppm / ° C. or less, preferably 15 ppm / ° C. or less and 50 to 90% of excellent light transmittance. Indicates.

Hereinafter, the present invention will be described in more detail by way of examples. However, the following examples are intended to illustrate the present invention, which does not limit the present invention.

Example 1 Preparation of Composite Film (Sheet) Containing Organic Nanofibers

The photocurable resin binder is impregnated with a photocurable PET fiber fabric (50 mm × 50 mm × 90 μm) and then sandwiched between glasses with a spacer of 100 μm. The upper slide was gently pressed to remove bubbles, and then reacted at 80 W / cm for 3 minutes in a photocuring machine, and then the glass was removed to obtain a light-transmissive composite film having a thickness of 130 μm shown in FIG. 1. Although a glass having a spacer of 100 mu m was used, a light-transmissive composite film having a thickness of 130 mu m was obtained due to the viscosity of the composition and the volume change during curing.

The photocurable resin binder is 5 wt% photoinitiator (Irgacure 184), 15 wt% trimethylolpropane triacrylate, 4 wt% phenol (EO) 2 acrylate, 16 wt% lauryl acrylate, bisphenol-A epoxy diacrylate oligomer 30 wt% of aliphatic urethane diacrylate oligomer was prepared by combining.

The diameter of the PET fiber in the PET fiber fabric was 300 nm, the CTE of the fiber was 3.3ppm / ℃. On the other hand, the content of the resin binder was 50wt% in the content ratio of the polymer resin binder and the textile fabric.

The light-transmissive composite film prepared in Example 1 shows 82% light transmittance (evaluated by UV-Vis spectrometer), and as shown in FIG. 1, it is transparent and suitable for use in an optical substrate. Could know.

Example 2 Preparation of Composite Film (Sheet) Containing Organic Nanofibers

A light-transmissive composite film was prepared in the same manner as in Example 1 except that the type of the fiber fabric was PEN. The diameter of the used PEN fiber was 500 nm and the CTE of the fiber was 3.0 ppm / 占 폚.

The light-transmissive composite film prepared in Example 2 exhibited 80% light transmittance (evaluated by UV-Vis spectrometer), and was found to be suitable for use in an optical substrate.

Comparative Example 1: Composite Film Containing Silica Filler

5 g of methylene chloride was added to 3 g of the photocurable polymer resin binder of Example 1 and 0.6 g of nano silica (Degussa, R812 (trade name), particle size 20 nm), followed by mixing for 20 minutes using a mixer. Bubbles in the mixed solution were removed by sonication and then the solution was bar cast onto a glass substrate. The cast film was reacted for 5 minutes at 80 W / cm in a photocuring machine to obtain a photocurable silica nanocomposite film having a thickness of 70 µm. The composite film showed 80% light transmittance as measured by UV-Vis spectrometer.

Comparative Example 2: Composite Film Preparation Comprising Glass Fibers

After impregnating a glass fiber fabric (diameter of glass fiber ~ 20㎛, refractive index ~ 1.55) (50 mm x 50 mm x 90㎛) to the photocurable polymer composition of Example 1, it has a spacer of 100㎛ Sandwiched between slide glass. The upper plate slide was gently pressed to remove bubbles, and then reacted for 3 minutes at 80 W / cm in a photocuring machine, and then the slide glass was removed to obtain a composite film (thickness: 100 μm). The composite film was evaluated by UV-Vis spectrometer showed a 30% light transmittance, from which it was confirmed that it is difficult to manufacture a light-transmissive composite film for an optical substrate.

Thermal expansion characteristic evaluation :

The thermal expansion characteristics of the light-transmissive composite films obtained in Examples 1 and 2 and Comparative Examples 1 and 2 using TMA (Thermal Mechanical Analyzer) were evaluated at a temperature rising rate of 5 ° C./min in a temperature range of room temperature to 100 ° C. 1 is shown.

As shown in Table 1, the light-transmissive composite films (sheets) of Examples 1 and 2 had CTEs of 15 ppm / ° C and 14 ppm / ° C, respectively, at a temperature range of 30 to 50 ° C., and 5.0 ppm at 50 to 100 ° C., respectively. By showing the CTE of / ℃, it was confirmed that it can be applied to the flexible substrate process that proceeds at a temperature of about 120 ℃ or less without problems such as peeling. Meanwhile, the silica nanocomposite film of Comparative Example 1 exhibited a very high CTE value of 190 ppm / ° C., and the composite containing glass fiber of Comparative Example 2 had a CTE of 14 ppm / ° C. in a temperature range of 30 to 50 ° C. At 50 to 100 ° C, a CTE of 3.5 ppm / ° C was shown. However, the composite containing the glass fiber of Comparative Example 2 was not suitable for use as a light-transmissive composite film for an optical substrate in view of light transmittance as described above.

Thermal Expansion Properties of Translucent Composite Films (Sheets) CTE
(ppm / ℃) 30 ~ 50 ℃ 50 ~ 100 ℃ Example 1 15 5.0 PET Nanofiber Composite Example 2 14 5.0 PEN Nanofiber Composite Comparative Example 1 190 Silica filler composite Comparative Example 2 14 3.5 Glass fiber composite

Claims (9)

Curable polymer resin binder and fiber diameter less than 500nm, PET (polyethyleneterephthalate), nylon, PEN (polyethylene naphthalate), PP (polypropylene), PES (polyethersulfone), PVDF (polyvinylidene fluoride), PPS (polyphenylene sulfide), PEEK (polyetheretherketone) ), Aromatic polyester, or organic nanofibers of a liquid crystalline polymer,
The curable polymer resin binder may be epoxy acrylates, urethane acrylates, polyester acrylates, acrylic acrylates, polybutadiene acrylates, silicone acrylates, melamine acrylates, dendrite acrylates, alicyclic Photocurable polymer resin binder or at least one oligomer selected from the group consisting of group epoxys, aromatic epoxys, aliphatic cyclic epoxys, and oxetanes, or epoxy resins, phenol resins, polyimide resins, polyester resins , Allyl ester resin, bismaleimide resin, isocyanate resin, polyphenylene ether resin, acrylic resin, melamine resin, silicone resin, benzoxadine resin, urea resin, phenol resin, alkyd resin, furan resin, polyurethane resin and Line from the group consisting of aniline resins And at least a kind of a thermosetting polymer resin,
Polymer-organic nanofiber composite is a polymer-organic nanofiber composite, characterized in that the CTE is less than 15 ppm / ℃.
The polymer-organic nanofiber composite according to claim 1, wherein the polymer-organic nanofiber composite comprises a polymer resin binder and an organic nanofiber in a 10/90 to 90/10 weight ratio.
delete The polymer-organic nanofiber composite of claim 1, wherein the organic nanofibers have a CTE of 50 ppm / ° C. or less.
The method of claim 1, wherein the organic nanofibers are woven, knitted, nonwoven, polymer-organic nanofibers, characterized in that the unidirection multilayer (short cut) form comprising a plurality of layers arranged in one direction Complex.
delete The polymer-organic nanofiber composite according to claim 1, wherein the polymer-organic nanofiber composite has a light transmittance of 50 to 90%.
Translucent composite film formed from the polymer-organic nanofiber composite of claim 1, 2, 4, 5, or 7.
The transparent composite film of claim 8, wherein the transparent composite film is used as a flexible display substrate.

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