Packaging composition, packaging material and preparation method thereof, and electronic device assembly

Abstract

The present invention relates to the field of electronic device component preparation, and discloses a packaging composition, packaging material and preparation method thereof, and electronic device component. The composition includes a polymer matrix and an auxiliary agent, and the polymer matrix includes a hyperbranched polyethylene and an optional ethylene and alpha-olefin copolymer. The polymer matrix is ​​blended with the auxiliary agent, and melt extruded into a film after being allowed to stand at a constant temperature, and the packaging material is obtained after cooling and cutting. Hyperbranched polyethylene with a specific side chain type and quantity is added to the packaging composition provided by the present invention, which has a higher cross-linking speed during processing, can shorten the curing time when preparing the packaging film, thereby improving the production efficiency of preparing electronic device components and reducing energy consumption, while shortening the residence time of the components under high temperature and high pressure, and can reduce the defective rate.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic device assembly preparation, and in particular to a packaging composition, a packaging material and a preparation method thereof, and an electronic device assembly. Background Art

[0002] Photovoltaic power generation, as one of the most competitive forms of new energy, has received great attention. Photovoltaic modules are integrated components that convert solar energy into electrical energy. The encapsulation material of photovoltaic cells mainly plays the role of protecting the cells and is a key material that affects the service life of photovoltaic modules. Therefore, the performance of photovoltaic film is the reliability guarantee for the stable operation of photovoltaic modules outdoors.

[0003] As the carbon peak and carbon neutrality goals of various countries become increasingly specific, the photovoltaic industry will maintain rapid expansion in the medium and long term, driving the growth in demand for encapsulation films. Coupled with the impact of the international situation and the epidemic in recent years, the supply of resins, the raw materials for films, has been tight, and prices have soared, which has significantly increased the cost of films and increased the cost control pressure on downstream component manufacturers. Currently, the commonly used photovoltaic encapsulation materials are ethylene and α-olefin copolymers (POE) and ethylene-vinyl acetate copolymers (EVA). EVA film has become the mainstream encapsulation material in the current market due to its price advantages and processing performance advantages, accounting for about 52%; POE film is the mainstream encapsulation material for double-glass modules due to its unique resistance to potential induced degradation (PID) performance, as well as its high resistivity and non-hydrolysis.

[0004] In this context, the research and development of new hyperbranched polyethylene elastomers has become one of the hot spots. Its structure is similar to that of POE resin, and its melt flow rate and molecular weight can be adjusted according to the actual needs of photovoltaic film. Therefore, it also has the characteristics of excellent weather resistance, high volume resistivity, anti-PID performance, and no acidic substance release of conventional POE resin. At the same time, the soft segment in the elastomer molecular chain can provide more tertiary carbon atoms, thereby increasing the molecular polarity and bonding ability, and accelerating the cross-linking speed, which can further optimize the existing film formula and component lamination process. In addition, the raw materials of the resin are simple, and the resin cost has a greater advantage than POE and EVA, so it can be used as a competitive new encapsulation film for photovoltaic modules.

[0005] However, the existing packaging film using POE as raw material has low molecular polarity, relatively low side chain content, and relatively few entanglements between molecular chains, so that the probability of reaction between free radical groups generated during curing is relatively low. Therefore, more curing time is required to achieve a suitable degree of cross-linking, and the lamination time is prolonged, which, on the one hand, affects the output and increases energy consumption simultaneously; on the other hand, the components stay at high temperature for a longer time, which affects other properties of the components and increases the defective rate of the components. Summary of the invention

[0006] The purpose of the present invention is to overcome the problem of long curing time of encapsulation film in the prior art and to provide an encapsulation composition, an encapsulation material and a preparation method thereof, as well as an electronic device assembly.

[0007] In order to achieve the above object, the first aspect of the present invention provides a packaging composition, wherein the composition comprises a polymer matrix and an auxiliary agent, the polymer matrix comprises a hyperbranched polyethylene and an optional copolymer of ethylene and α-olefin;

[0008] The hyperbranched polyethylene comprises a polyethylene main chain and a plurality of C1 or higher alkyl side chains bonded to the polyethylene main chain; wherein the total number of methyl side chains corresponding to every 1000 carbon atoms in the polyethylene main chain is 30-120, the total number of ethyl, propyl, butyl and pentyl side chains is 5-60, and the total number of C6 or higher alkyl side chains is 2-50.

[0009] A second aspect of the present invention provides a packaging material, wherein the packaging material is prepared from the composition described in the first aspect.

[0010] The third aspect of the present invention provides a method for preparing a packaging material, which comprises the following steps: blending a polymer matrix with an additive, melt-extruding the mixture into a film, cooling and cutting the mixture to obtain the packaging material;

[0011] wherein the polymer matrix comprises hyperbranched polyethylene and optionally a copolymer of ethylene and α-olefin;

[0012] The hyperbranched polyethylene comprises a polyethylene main chain and a plurality of C1 or higher alkyl side chains bonded to the polyethylene main chain; wherein the total number of methyl side chains corresponding to every 1000 carbon atoms in the polyethylene main chain is 30-120, the total number of ethyl, propyl, butyl and pentyl side chains is 5-60, and the total number of C6 or higher alkyl side chains is 2-50.

[0013] The fourth aspect of the present invention provides a packaging material obtained by the method described in the third aspect.

[0014] A fifth aspect of the present invention provides an electronic device assembly, which includes the packaging material described in the first and fourth aspects.

[0015] Through the above technical solution, the beneficial technical effects achieved by the present invention are as follows:

[0016] (1) The encapsulation composition provided by the present invention contains a hyperbranched polyethylene with a specific side chain type and amount, which has a high cross-linking speed during processing, can shorten the curing time when preparing the encapsulation film, thereby improving the production efficiency of preparing electronic device components and reducing energy consumption, while shortening the residence time of the components under high temperature and high pressure, which can reduce the defective rate.

[0017] (2) The packaging material provided by the present invention has excellent light transmittance, cross-linking degree, peel strength, volume resistivity, water vapor permeability and outdoor aging resistance, all of which are better than the industry standards, and is low in cost and can meet photovoltaic packaging applications. It can be used as a competitive new type of solar cell packaging film. DETAILED DESCRIPTION

[0018] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0019] The first aspect of the present invention provides a packaging composition, wherein the composition comprises a polymer matrix and an auxiliary agent, the polymer matrix comprises a hyperbranched polyethylene and an optional copolymer of ethylene and an α-olefin;

[0020] The hyperbranched polyethylene comprises a polyethylene main chain and a plurality of C1 or higher alkyl side chains bonded to the polyethylene main chain; wherein the total number of methyl side chains corresponding to every 1000 carbon atoms in the polyethylene main chain is 30-120, the total number of ethyl, propyl, butyl and pentyl side chains is 5-60, and the total number of C6 or higher alkyl side chains is 2-50.

[0021] It can be further understood that the molecular chain of the hyperbranched polyethylene may comprise the structural units shown below: Wherein, R is one of C1 or higher alkyl groups, including isomers, such as methyl, ethyl, propyl, butyl, pentyl or C6 or higher alkyl groups. Wherein, C6 or higher alkyl side chains refer to alkyl side chains with 6 or higher carbon atoms detected.

[0022] The invention adds hyperbranched polyethylene with specific side chain type and quantity to the encapsulation composition. Since the side chain contains specific alkyl type and quantity, there are more chain entanglements between molecular chains, and the probability of reaction between free radicals at the curing point is greater, so that the cross-linking speed is higher during processing, and the curing time when preparing the encapsulation film can be shortened, thereby improving the production efficiency of preparing electronic device components and reducing energy consumption, and at the same time shortening the residence time of the components under high temperature and high pressure, which can reduce the defective rate.

[0023] In the present invention, the number of side chains in the molecular chain of the hyperbranched polyethylene is determined by hydrogen nuclear magnetic spectrum.

[0024] The hyperbranched polyethylene in the present invention is obtained by solution polymerization of ethylene using the following catalyst:

[0025]

[0026] Among them, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 and R 7 are independently selected from hydrogen, halogen, nitro, C1-C 10 Straight or branched alkyl and C1-C 10 One of the straight-chain or branched alkoxy groups;

[0027] Among them, when R 3 When it is hydrogen, R 1 and R 5 Not simultaneously methyl, ethyl or isopropyl;

[0028] When R 3 When it is methyl, R 1 and R 5 Not simultaneously methyl or ethyl;

[0029] X 1 and X 2 Each is independently selected from one of F, Cl, Br and I.

[0030] Specifically, the catalyst is selected from at least one of the following complexes:

[0031] Complex Ni1: R 4 =R 5 =Me,X 1 =X 2 =Br, other substituents are H;

[0032] Complex Ni2: R 1 =R 4 =R 5 =Me,X 1 =X 2 =Br, other substituents are H;

[0033] Complex Ni3: R 1 =R 3 =R 5 =Et,X 1 =X 2 =Br, other substituents are H;

[0034] Complex Ni4: R 1 =Et, R 5=Me,X 1 =X 2 =Br, other substituents are H;

[0035] Complex Ni5: R 1 =iPr,R 5 =Me,X 1 =X 2 =Br, and the other substituents are H.

[0036] In actual operation, the structure of the obtained hyperbranched polyethylene, such as the number of side chains, can be regulated by adjusting the specific structure of the above catalyst and the polymerization conditions. The polymerization conditions may include: a polymerization temperature of 0-100°C, a polymerization pressure of 0.1-3MPa, and a polymerization time of 10-60min.

[0037] The total number of methyl side chains per 1000 carbon atoms in the polyethylene main chain can be selected from 30, 40, 50, 60, 70, 80, 90, 100, 110, and 120.

[0038] The total number of ethyl, propyl, butyl and pentyl side chains corresponding to every 1000 carbon atoms in the polyethylene main chain can be selected to be 5, 10, 20, 30, 40, 50 or 60.

[0039] The total number of C6 or higher alkyl side chains per 1000 carbon atoms in the polyethylene main chain can be selected from 2, 5, 10, 20, 30, 40, and 50.

[0040] According to some embodiments of the present invention, the total number of methyl side chains per 1000 carbon atoms in the polyethylene main chain is 60-110, preferably 65-95.

[0041] According to some preferred embodiments of the present invention, the total number of ethyl, propyl, butyl and pentyl side chains per 1000 carbon atoms in the polyethylene main chain is 10-40, preferably 15-35.

[0042] According to some preferred embodiments of the present invention, the total number of C6 and above alkyl side chains corresponding to every 1000 carbon atoms in the polyethylene main chain is 3-30, preferably 3-20.

[0043] According to some preferred embodiments of the present invention, the number average molecular weight of the hyperbranched polyethylene is 20,000-250,000 g / mol, for example, 20,000 g / mol, 40,000 g / mol, 80,000 g / mol, 120,000 g / mol, 150,000 g / mol, 200,000 g / mol, 220,000 g / mol, 250,000 g / mol, and any value within the range of any two of the above values, preferably 20,000-100,000 g / mol. In the present invention, the number average molecular weight of the hyperbranched polyethylene is controlled within the above range, so that the processing performance of the resin can be taken into account while ensuring the performance of the resin itself.

[0044] According to some preferred embodiments of the present invention, the melt flow rate of the hyperbranched polyethylene at 120°C and a load of 2.16 kg is 0.4-8 g / 10min, such as 0.4 g / 10min, 1 g / 10min, 2 g / 10min, 3 g / 10min, 4 g / 10min, 5 g / 10min, 6 g / 10min, 7 g / 10min, 8 g / 10min, and any value within the range of any two of the above values, preferably 0.5-6 g / 10min. In the present invention, the melt flow rate of the hyperbranched polyethylene is controlled within the above range to ensure the melt processing film-forming performance of the resin.

[0045] According to some preferred embodiments of the present invention, the density of the hyperbranched polyethylene is 0.8-0.9 g / cm 3 , for example 0.8 g / cm 3 , 0.82g / cm 3 , 0.84g / cm 3 , 0.86g / cm 3 , 0.88g / cm 3 , 0.9g / cm 3 , and any value within the range of any two of the above values, preferably 0.85-0.89 g / cm 3 In the present invention, the density of the hyperbranched polyethylene is controlled within the above range, and it can be clearly seen that the side chain content of the resin is greater than that of conventional polyethylene, such as low-density polyethylene, high-density polyethylene, linear low-density polyethylene, etc., because the more side chains there are, the larger the gaps between the molecular chains are, and the lower the density is.

[0046] In the present invention, the number average molecular weight is measured by gel chromatography (GPC), the melt flow rate is measured by a melt flow velocity meter according to GB / T3682.1-2018, and the density is measured by a density meter according to GB / T1033.1-2008.

[0047] According to some embodiments of the present invention, the α-olefin in the copolymer of ethylene and α-olefin is selected from at least one of 1-butene, 1-hexene, 1-octene, 1-decene and 1-dodecene.

[0048] According to some preferred embodiments of the present invention, the ethylene and α-olefin copolymer is an ethylene-octene copolymer and / or an ethylene-butene copolymer.

[0049] According to some preferred embodiments of the present invention, the number average molecular weight of the copolymer of ethylene and α-olefin is 25,000-40,000 g / mol.

[0050] According to some preferred embodiments of the present invention, the α-olefin content in the ethylene and α-olefin copolymer is not less than 20%. In the present invention, when the α-olefin content in the ethylene and α-olefin copolymer is not less than 20%, the crystallization performance of the ethylene and α-olefin copolymer decreases, and a soft segment required for a thermoplastic elastomer is formed in the resin. In addition, the crystallization performance decreases, which can improve the light transmittance of the polymer and is more suitable for photovoltaic applications.

[0051] According to some embodiments of the present invention, based on 100 parts by weight of the polymer matrix, the polymer matrix includes 5-100 parts by weight of hyperbranched polyethylene and 0-95 parts by weight of ethylene and α-olefin copolymer. Using the hyperbranched polyethylene and ethylene and α-olefin copolymer in the above weight range as the polymer matrix of the encapsulation composition, it is possible to utilize the advantages of the hyperbranched polyethylene while producing the film under existing processing conditions.

[0052] Taking 100 parts by weight of the polymer matrix as a benchmark, the hyperbranched polyethylene can be selected from 5 parts by weight, 10 parts by weight, 20 parts by weight, 30 parts by weight, 40 parts by weight, 50 parts by weight, 60 parts by weight, 70 parts by weight, 80 parts by weight, 90 parts by weight, 100 parts by weight, and any value in the range composed of any two of the above numerical values; the ethylene and alpha-olefin copolymer can be selected from 0 parts by weight, 5 parts by weight, 10 parts by weight, 20 parts by weight, 30 parts by weight, 40 parts by weight, 50 parts by weight, 60 parts by weight, 70 parts by weight, 80 parts by weight, 90 parts by weight, 95 parts by weight, and any value in the range composed of any two of the above numerical values.

[0053] According to some preferred embodiments of the present invention, based on 100 parts by weight of the polymer matrix, the polymer matrix comprises 50-100 parts by weight of the hyperbranched polyethylene and 0-50 parts by weight of the ethylene and α-olefin copolymer.

[0054] According to some embodiments of the present invention, the auxiliary agent includes at least one of a crosslinking agent, a co-crosslinking agent, a tackifier, an antioxidant, and an ultraviolet light absorber. Those skilled in the art can improve relevant properties by selecting auxiliary agents.

[0055] According to some preferred embodiments of the present invention, based on 100 parts by weight of the polymer matrix, the weight of the crosslinking agent is 0.3-3 parts, for example 0.3 parts, 1 part, 2 parts, 3 parts, and any value within the range of any two of the above values, preferably 0.5-2 parts.

[0056] According to some preferred embodiments of the present invention, based on 100 parts by weight of the polymer matrix, the weight of the auxiliary cross-linking agent is 0.3-3 parts, for example 0.3 parts, 1 part, 2 parts, 3 parts, and any value within the range of any two of the above values, preferably 0.5-2 parts.

[0057] According to some preferred embodiments of the present invention, based on 100 parts by weight of the polymer matrix, the weight of the tackifier is 0.3-3 parts, for example 0.3 parts, 1 parts, 2 parts, 3 parts, and any value within the range of any two of the above values, preferably 0.5-2 parts.

[0058] According to some preferred embodiments of the present invention, based on 100 parts by weight of the polymer matrix, the weight of the antioxidant is 0.1-3 parts, for example, 0.1 parts, 0.3 parts, 1 parts, 2 parts, 3 parts, and any value within the range of any two of the above values, preferably 0.1-2 parts.

[0059] According to some preferred embodiments of the present invention, based on 100 parts by weight of the polymer matrix, the weight of the ultraviolet light absorber is 0.1-3 parts, for example, 0.1 parts, 0.3 parts, 1 parts, 2 parts, 3 parts, and any value within the range of any two of the above values, preferably 0.1-2 parts.

[0060] According to some preferred embodiments of the present invention, the cross-linking agent is selected from at least one of tert-butyl peroxy-2-ethylhexyl carbonate (TBEC), tert-amyl peroxy (2-ethylhexyl) carbonate (TAEC), 2,5-di-tert-butyl peroxy-2,5-dimethylhexane (bis-25), tert-butyl peroxy maleate (TBPMA), tert-butyl peroxyisopropyl carbonate (TBIC), tert-butyl peroxyacetate (TBPA) and 4,4-bis(tert-butylperoxy)butyl valerate (VA).

[0061] According to some preferred embodiments of the present invention, the auxiliary cross-linking agent is selected from at least one of triallyl isocyanurate (TAIC), trimethylolpropane trimethacrylate (TMPTMA), trimethallyl isocyanate (TMAIC) and triallyl cyanurate (TAC).

[0062] According to some preferred embodiments of the present invention, the adhesion promoter is selected from at least one of 3-aminopropyltriethoxysilane (KH550), γ-glycidyloxypropyltrimethoxysilane (KH560), γ-methacryloxypropyltrimethoxysilane (KH570) and vinyltriacetoxysilane (KH188).

[0063] According to some preferred embodiments of the present invention, the antioxidant is selected from at least one of tris[2.4-di-tert-butylphenyl]phosphite (antioxidant 168), pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (antioxidant 1010), β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (antioxidant 1076), 2,2'-methylenebis(4-methyl-6-tert-butylphenol) (antioxidant 2246) and pentaerythritol distearyl diphosphite (antioxidant 618).

[0064] According to some preferred embodiments of the present invention, the ultraviolet light absorber is selected from at least one of 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole (UV-326), 2-hydroxy-4-n-octyloxybenzophenone (UV-531), poly(4-hydroxy-2,2,6,6-tetramethyl-1-piperidinylethanol) succinate (UV-622) and bis(2,2,6,6-tetramethylpiperidinyl) sebacate (UV-770).

[0065] A second aspect of the present invention provides a packaging material, wherein the packaging material is prepared from the composition described in the first aspect.

[0066] According to some preferred embodiments of the present invention, the packaging material is a packaging film.

[0067] The third aspect of the present invention provides a method for preparing a packaging material, which comprises the following steps: blending a polymer matrix with an auxiliary agent, allowing the mixture to stand at a constant temperature, and then melt-extruding the mixture into a film, and then cooling and cutting the mixture to obtain the packaging material;

[0068] wherein the polymer matrix comprises hyperbranched polyethylene and optionally a copolymer of ethylene and α-olefin;

[0069] The hyperbranched polyethylene comprises a polyethylene main chain and a plurality of C1 or higher alkyl side chains bonded to the polyethylene main chain; wherein the total number of methyl side chains corresponding to every 1000 carbon atoms in the polyethylene main chain is 30-120, the total number of ethyl, propyl, butyl and pentyl side chains is 5-60, and the total number of C6 or higher alkyl side chains is 2-50.

[0070] According to some embodiments of the present invention, the constant temperature static temperature is 35-60°C, such as 35°C, 40°C, 50°C, 60°C, and any value within the range of any two of the above values, preferably 40-55°C. In the present invention, if the constant temperature static temperature is too low, part of the additives will remain solid and cannot be dispersed; if the constant temperature static temperature is too high, on the one hand, energy will be wasted and energy consumption will be increased; on the other hand, the resin melting point is low, and if the temperature is too high and close to the melting temperature of the resin, the resin will be agglomerated, which is not conducive to subsequent processing.

[0071] According to some preferred embodiments of the present invention, the constant temperature standing time is 1.5-5h, such as 1.5h, 2h, 3h, 4h, 5h, and any value within the range of any two of the above values, preferably 2-4h. In the present invention, if the constant temperature standing time is too short, the resin cannot completely absorb the additive, resulting in uneven distribution of the additive and partial over-crosslinking; if the constant temperature standing time is too long, the production efficiency is affected, the output is reduced, and the energy consumption is increased.

[0072] According to some preferred embodiments of the present invention, the extrusion temperature is 70-120°C, for example, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, and any value within the range of any two of the above values, preferably 80-100°C. In the present invention, if the extrusion temperature is too low, the resin cannot be completely plasticized and melted, which affects the dispersion of the additives and the appearance of the film; if the extrusion temperature is too high, the peroxide is promoted to be homogenously decomposed to form free radicals during the extrusion stage, which changes the fluidity of the material and affects the production of the film.

[0073] According to some embodiments of the present invention, the total number of methyl side chains per 1000 carbon atoms in the polyethylene main chain is 60-110, preferably 65-95.

[0074] According to some preferred embodiments of the present invention, the total number of ethyl, propyl, butyl and pentyl side chains per 1000 carbon atoms in the polyethylene main chain is 10-40, preferably 15-35.

[0075] According to some preferred embodiments of the present invention, the total number of C6 and above alkyl side chains corresponding to every 1000 carbon atoms in the polyethylene main chain is 3-30, preferably 3-20.

[0076] According to some preferred embodiments of the present invention, the number average molecular weight of the hyperbranched polyethylene is 20,000-250,000 g / mol, preferably 20,000-100,000 g / mol.

[0077] According to some preferred embodiments of the present invention, the hyperbranched polyethylene has a melt flow rate of 0.4-8 g / 10 min, preferably 0.5-6 g / 10 min at 120° C. and a load of 2.16 kg.

[0078] According to some preferred embodiments of the present invention, the density of the hyperbranched polyethylene is 0.8-0.9 g / cm 3 , preferably 0.85-0.89 g / cm 3 .

[0079] According to some embodiments of the present invention, the α-olefin in the copolymer of ethylene and α-olefin is selected from at least one of 1-butene, 1-hexene, 1-octene, 1-decene and 1-dodecene.

[0080] According to some preferred embodiments of the present invention, the ethylene and α-olefin copolymer is an ethylene-octene copolymer and / or an ethylene-butene copolymer.

[0081] According to some preferred embodiments of the present invention, the number average molecular weight of the copolymer of ethylene and α-olefin is 25,000-40,000 g / mol.

[0082] According to some preferred embodiments of the present invention, the α-olefin content in the copolymer of ethylene and α-olefin is not less than 20%.

[0083] According to some embodiments of the present invention, based on 100 parts by weight of the polymer matrix, the polymer matrix comprises 5-100 parts by weight of the hyperbranched polyethylene and 0-95 parts by weight of the ethylene and α-olefin copolymer.

[0084] According to some preferred embodiments of the present invention, based on 100 parts by weight of the polymer matrix, the polymer matrix comprises 50-100 parts by weight of the hyperbranched polyethylene and 0-50 parts by weight of the ethylene and α-olefin copolymer.

[0085] According to some embodiments of the present invention, the auxiliary agent includes at least one of a cross-linking agent, a co-cross-linking agent, a tackifier, an antioxidant and an ultraviolet light absorber.

[0086] According to some preferred embodiments of the present invention, based on 100 parts by weight of the polymer matrix, the weight of the crosslinking agent is 0.3-3 parts, preferably 0.5-2 parts.

[0087] According to some preferred embodiments of the present invention, based on 100 parts by weight of the polymer matrix, the weight of the auxiliary cross-linking agent is 0.3-3 parts, preferably 0.5-2 parts.

[0088] According to some preferred embodiments of the present invention, based on 100 parts by weight of the polymer matrix, the weight of the tackifier is 0.3-3 parts, preferably 0.5-2 parts.

[0089] According to some preferred embodiments of the present invention, based on 100 parts by weight of the polymer matrix, the weight portion of the antioxidant is 0.1-3 parts, preferably 0.1-2 parts.

[0090] According to some preferred embodiments of the present invention, based on 100 parts by weight of the polymer matrix, the weight of the ultraviolet light absorber is 0.1-3 parts, preferably 0.1-2 parts.

[0091] According to some preferred embodiments of the present invention, the cross-linking agent is selected from at least one of tert-butyl peroxy-2-ethylhexyl carbonate (TBEC), tert-amyl peroxy (2-ethylhexyl) carbonate (TAEC), 2,5-di-tert-butyl peroxy-2,5-dimethylhexane (bis-25), tert-butyl peroxy maleate (TBPMA), tert-butyl peroxyisopropyl carbonate (TBIC), tert-butyl peroxyacetate (TBPA) and 4,4-bis(tert-butylperoxy)butyl valerate (VA).

[0092] According to some preferred embodiments of the present invention, the auxiliary cross-linking agent is selected from at least one of triallyl isocyanurate (TAIC), trimethylolpropane trimethacrylate (TMPTMA), trimethallyl isocyanate (TMAIC) and triallyl cyanurate (TAC).

[0093] According to some preferred embodiments of the present invention, the adhesion promoter is selected from at least one of 3-aminopropyltriethoxysilane (KH550), γ-glycidyloxypropyltrimethoxysilane (KH560), γ-methacryloxypropyltrimethoxysilane (KH570) and vinyltriacetoxysilane (KH188).

[0094] According to some preferred embodiments of the present invention, the antioxidant is selected from at least one of tris[2.4-di-tert-butylphenyl]phosphite (antioxidant 168), pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (antioxidant 1010), β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (antioxidant 1076), 2,2'-methylenebis(4-methyl-6-tert-butylphenol) (antioxidant 2246) and pentaerythritol distearyl diphosphite (antioxidant 618).

[0095] According to some preferred embodiments of the present invention, the ultraviolet light absorber is selected from at least one of 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole (UV-326), 2-hydroxy-4-n-octyloxybenzophenone (UV-531), poly(4-hydroxy-2,2,6,6-tetramethyl-1-piperidinylethanol) succinate (UV-622) and bis(2,2,6,6-tetramethylpiperidinyl) sebacate (UV-770).

[0096] According to a particularly preferred embodiment of the present invention, a method for preparing a packaging material comprises the following steps: blending a polymer matrix with an additive, and melting the mixture after standing at a constant temperature of 40-55° C. for 2-4 hours, and then extruding the mixture into a film at 80-100° C., and obtaining the packaging material after cooling and cutting;

[0097] Wherein, based on 100 parts by weight of the polymer matrix, the polymer matrix comprises 5-100 parts by weight of hyperbranched polyethylene and 0-95 parts by weight of ethylene and α-olefin copolymer;

[0098] The hyperbranched polyethylene comprises a polyethylene main chain and a plurality of C1 or higher alkyl side chains bonded to the polyethylene main chain; wherein the total number of methyl side chains corresponding to every 1000 carbon atoms in the polyethylene main chain is 60-110, the total number of ethyl, propyl, butyl and pentyl side chains is 10-40, and the total number of C6 or higher alkyl side chains is 3-30.

[0099] The fourth aspect of the present invention provides a packaging material obtained by the method described in the third aspect.

[0100] A fifth aspect of the present invention provides an electronic device assembly, which includes the packaging material described in the first and fourth aspects.

[0101] According to some preferred embodiments of the present invention, the electronic device assembly is a photovoltaic assembly.

[0102] The encapsulation material provided by the present invention has a short curing time during preparation, which can improve the production efficiency of preparing electronic device components and reduce energy consumption, and at the same time shorten the residence time of the components under high temperature and high pressure, which can reduce the defective rate. In addition, the various properties of the encapsulation material are better than the industry standard requirements, and the cost is low, which can meet the photovoltaic encapsulation application and can be used as a competitive new solar cell encapsulation film.

[0103] The present invention will be described in detail below through examples.

[0104] In the following examples and comparative examples, if no specific conditions are specified, the experiments were carried out under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used, if no manufacturer is specified, are all conventional products that can be obtained through commercial channels.

[0105] For ease of explanation, the methyl side chain in the hyperbranched polyethylene is represented by ZM, the ethyl, propyl, butyl and pentyl side chains are represented by ZN, and the C6 or higher alkyl side chain is represented by ZL.

[0106] In the examples and comparative examples, the parameters of the hyperbranched polyethylene used are shown in Table 1, and the ethylene and α-olefin copolymer used is DOW ENGAGE PV8669, which is an ethylene-octene copolymer available from the market.

[0107] Test method:

[0108] The number of side chains in the molecular chain of the hyperbranched polyethylene is determined by nuclear magnetic hydrogen spectrum, the number average molecular weight is determined by gel chromatography (GPC), the melt flow rate is determined by a melt flow velocity meter, and the density is determined by a density meter.

[0109] Example 1

[0110] This example is used to illustrate the preparation of the packaging film.

[0111] The encapsulating composition was prepared according to the formulation in Table 2.

[0112] After the components are mixed evenly, they are allowed to stand at a constant temperature of 45°C for 2 hours, and then the materials are put into an extruder for extrusion at a temperature of 90°C. The extrudate undergoes the steps of cast film, cooling, slitting, and winding to obtain a transparent packaging film.

[0113] Embodiment 2-6

[0114] Examples 2-6 are used to illustrate the preparation of packaging films.

[0115] The encapsulation film was prepared according to the method of Example 1, except that the encapsulation composition was prepared according to the formula in Table 2.

[0116] Example 7

[0117] This example is used to illustrate the preparation of the packaging film.

[0118] The encapsulating composition was prepared according to the formulation in Table 2.

[0119] After the components are mixed evenly, they are allowed to stand at a constant temperature of 40°C for 2 hours, and then the materials are put into an extruder for extrusion at a temperature of 80°C. The extrudate undergoes film casting, cooling, slitting, and winding processes to obtain a transparent packaging film with a thickness of 0.5 mm.

[0120] Example 8

[0121] This example is used to illustrate the preparation of the packaging film.

[0122] The encapsulating composition was prepared according to the formulation in Table 2.

[0123] After the components are mixed evenly, they are kept at a constant temperature of 55°C for 4 hours, and then the materials are put into an extruder for extrusion at a temperature of 100°C. The extrudate undergoes film casting, cooling, slitting, and winding processes to obtain a transparent packaging film with a thickness of 0.5 mm.

[0124] Example 9

[0125] This example is used to illustrate the preparation of the packaging film.

[0126] The encapsulating composition was prepared according to the formulation in Table 2.

[0127] After the components are mixed evenly, they are kept at a constant temperature of 35°C for 5 hours, and then the materials are put into an extruder for extrusion at a temperature of 70°C. The extrudate undergoes film casting, cooling, slitting, and winding processes to obtain a transparent packaging film with a thickness of 0.5 mm.

[0128] Example 10

[0129] This example is used to illustrate the preparation of the packaging film.

[0130] The encapsulating composition was prepared according to the formulation in Table 2.

[0131] After the components are mixed evenly, they are allowed to stand at a constant temperature of 60°C for 1.5 hours, and then the materials are put into an extruder for extrusion at a temperature of 120°C. The extrudate undergoes film casting, cooling, slitting, and winding processes to obtain a transparent packaging film with a thickness of 0.5 mm.

[0132] Embodiment 11

[0133] This example is used to illustrate the preparation of the packaging film.

[0134] The encapsulating composition was prepared according to the formulation in Table 2.

[0135] After the components are mixed evenly, they are allowed to stand at a constant temperature of 50°C for 3 hours, and then the materials are put into an extruder for extrusion at a temperature of 90°C. The extrudate undergoes film casting, cooling, slitting, and winding processes to obtain a transparent packaging film with a thickness of 0.5 mm.

[0136] Example 12

[0137] This example is used to illustrate the preparation of the packaging film.

[0138] The encapsulating composition was prepared according to the formulation in Table 2.

[0139] After the components are mixed evenly, they are allowed to stand at a constant temperature of 52°C for 2.5 hours, and then the materials are put into an extruder for extrusion at a temperature of 110°C. The extrudate undergoes film casting, cooling, slitting, and winding processes to obtain a transparent packaging film with a thickness of 0.5 mm.

[0140] Comparative Example 1

[0141] The encapsulation film was prepared according to the method of Example 1, except that the encapsulation composition was prepared according to the formula in Table 2.

[0142] Table 1

[0143]

[0144] Table 2

[0145]

[0146] Table 2

[0147]

[0148]

[0149] Test Example 1

[0150] Examples 1-6 and Comparative Example 1 were tested as follows:

[0151] Peak curing speed and curing time Tc90: According to the national standard GB / T16584-1996, it is carried out in a rotorless rubber processing analyzer, the test temperature is 145°C, and the test time is 20 minutes.

[0152] Normally, the greater the peak cure speed, the shorter the time Tc90 required to reach 90% cure.

[0153] The test results are shown in Table 3.

[0154] Table 3

[0155]

[0156] Test Example 2

[0157] Photovoltaic embossed glass and PVDF back sheet were attached to the two surfaces of the encapsulation films obtained in Examples 7-12 and Comparative Example 1, respectively, and then laminated in a vacuum laminator.

[0158] According to the T / CPIA 0006-2017 industry standard, the transmittance, cross-linking degree, peel strength, volume resistivity, water vapor transmission rate, moisture and heat aging resistance and yellowing index were measured.

[0159] The performance test data of each sample is shown in Table 4:

[0160] Table 4

[0161]

[0162]

[0163] According to the results in Table 3, by comparing Examples 1-6 with Comparative Example 1, it can be found that the peak crosslinking speed of the hyperbranched polyethylene in the encapsulation composition of the present invention is significantly higher than that of the conventional photovoltaic-grade polyolefin copolymer currently used, and the curing time is also significantly shortened. When the polyolefin elastomer matrix partially or entirely adopts hyperbranched polyethylene, due to the high content of side chains of the hyperbranched polyethylene and more molecular chain entanglements, the crosslinking speed is significantly accelerated under the same processing conditions, thereby shortening the crosslinking curing time required for the photovoltaic module during the lamination process, which can effectively increase the output and reduce energy consumption on the one hand; on the other hand, it can shorten the residence time of the solar cell under high temperature and high pressure, and reduce the defective rate.

[0164] According to the results in Table 4, by comparing Examples 7-12 and Comparative Example 2, it can be found that using hyperbranched polyethylene to partially or completely replace the existing photovoltaic-grade POE can give the encapsulation film better cross-linking degree, adhesion to glass and water vapor permeability.

[0165] By comparing Examples 7-12 with the requirements of the industry standard T / CPIA 006-2017, hyperbranched polyethylene is used to partially or completely replace the existing photovoltaic-grade POE, and the transmittance, cross-linking degree, peel strength, volume resistivity, water vapor permeability, moisture and heat aging resistance and yellowing index are all better than the industry standard requirements.

[0166] When hyperbranched polyethylene partially or completely replaces the existing photovoltaic-grade POE, the photovoltaic encapsulation film prepared by the present invention still has good optical properties, adhesive properties, suitable cross-linking degree, excellent aging resistance and electrical insulation, and some properties are close to or better than the existing photovoltaic POE encapsulation film. In addition, the cost of hyperbranched polyethylene is significantly lower than that of the existing photovoltaic-grade POE, and is not monopolized by foreign technology. At the same time, the cross-linking curing speed is significantly higher than that of POE, which can improve the production efficiency of photovoltaic modules, reduce energy consumption, and reduce the defective rate. Therefore, from the perspective of performance and comprehensive cost, the present invention has obvious advantages over the prior art.

[0167] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A packaging composition, characterized in that The composition comprises a polymer matrix and an adjuvant, wherein the polymer matrix comprises a hyperbranched polyethylene and optionally a copolymer of ethylene and an α-olefin; The hyperbranched polyethylene comprises a polyethylene main chain and a plurality of C1 or higher alkyl side chains bonded to the polyethylene main chain; wherein the total number of methyl side chains corresponding to every 1000 carbon atoms in the polyethylene main chain is 80-90, the total number of ethyl, propyl, butyl and pentyl side chains is 20-30, and the total number of C6 or higher alkyl side chains is 10-20; the density of the hyperbranched polyethylene is 0.85-0.89 g / cm 3 ; Hyperbranched polyethylene is obtained by solution polymerization of ethylene using the following catalysts: Among them, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 and R 7 are independently selected from hydrogen, halogen, nitro, C1-C 10 Straight or branched alkyl and C1-C 10 One of the straight-chain or branched alkoxy groups; Among them, when R 3 When it is hydrogen, R 1 and R 5 Not simultaneously methyl, ethyl or isopropyl; When R 3 When it is methyl, R 1 and R 5 Not simultaneously methyl or ethyl; X 1 and X 2 Each independently selected from one of F, Cl, Br and I; The number average molecular weight of the hyperbranched polyethylene is 20,000-100,000 g / mol; The hyperbranched polyethylene has a melt flow rate of 0.5-6 g / 10 min at 120° C. and a load of 2.16 kg; The ethylene and α-olefin copolymer is an ethylene-octene copolymer and / or an ethylene-butene copolymer; the number average molecular weight of the ethylene and α-olefin copolymer is 25,000-40,000 g / mol; the α-olefin content in the ethylene and α-olefin copolymer is not less than 20%; Based on 100 parts by weight of the polymer matrix, the polymer matrix comprises 50-100 parts by weight of the hyperbranched polyethylene and 0-50 parts by weight of the copolymer of ethylene and α-olefin.

2. The composition according to claim 1, wherein The auxiliary agent includes at least one of a cross-linking agent, a co-cross-linking agent, a tackifier, an antioxidant and an ultraviolet light absorber; Based on 100 parts by weight of the polymer matrix, the weight portion of the crosslinking agent is 0.3-3 parts; Based on 100 parts by weight of the polymer matrix, the weight portion of the auxiliary cross-linking agent is 0.3-3 parts; Based on 100 parts by weight of the polymer matrix, the weight portion of the tackifier is 0.3-3 parts; Based on 100 parts by weight of the polymer matrix, the weight portion of the antioxidant is 0.1-3 parts; Based on 100 parts by weight of the polymer matrix, the weight of the ultraviolet light absorber is 0.1-3 parts; The cross-linking agent is selected from at least one of tert-butyl peroxy-2-ethylhexyl carbonate, tert-amyl peroxy (2-ethylhexyl) carbonate, 2,5-di-tert-butyl peroxy-2,5-dimethylhexane, tert-butyl peroxymaleate, tert-butyl peroxyisopropyl carbonate, tert-butyl peroxyacetate and 4,4-bis (tert-butyl peroxy) butyl valerate; The auxiliary cross-linking agent is selected from at least one of triallyl isocyanurate, trimethylolpropane trimethacrylate, trimethallyl isocyanate and triallyl cyanurate; The tackifier is selected from at least one of 3-aminopropyltriethoxysilane, γ-glycidyloxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane and vinyltriacetoxysilane; The antioxidant is selected from at least one of tris[2,4-di-tert-butylphenyl]phosphite, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 2,2'-methylenebis(4-methyl-6-tert-butylphenol) and distearyl pentaerythritol diphosphite; The ultraviolet light absorber is selected from at least one of 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-hydroxy-4-n-octyloxybenzophenone, poly(4-hydroxy-2,2,6,6-tetramethyl-1-piperidinylethanol) succinate and bis(2,2,6,6-tetramethylpiperidinyl) sebacate.

3. The composition according to claim 2, wherein Based on 100 parts by weight of the polymer matrix, the weight portion of the crosslinking agent is 0.5-2 parts; Based on 100 parts by weight of the polymer matrix, the weight portion of the auxiliary cross-linking agent is 0.5-2 parts; Based on 100 parts by weight of the polymer matrix, the weight portion of the tackifier is 0.5-2 parts; Based on 100 parts by weight of the polymer matrix, the weight portion of the antioxidant is 0.1-2 parts; Based on 100 parts by weight of the polymer matrix, the weight portion of the ultraviolet light absorber is 0.1-2 parts.

4. A packaging material, characterized in that: The packaging material is made from the composition described in any one of claims 1 to 3; the packaging material is a packaging film.

5. A method for preparing a packaging material, characterized in that: The method comprises the following steps: blending a polymer matrix with an auxiliary agent, allowing the mixture to stand at a constant temperature, and then performing melt extrusion to form a film, and then cooling and cutting the mixture to obtain the packaging material; wherein the polymer matrix comprises hyperbranched polyethylene and optionally a copolymer of ethylene and α-olefin; The hyperbranched polyethylene comprises a polyethylene main chain and a plurality of C1 or higher alkyl side chains bonded to the polyethylene main chain; wherein the total number of methyl side chains corresponding to every 1000 carbon atoms in the polyethylene main chain is 80-90, the total number of ethyl, propyl, butyl and pentyl side chains is 20-30, and the total number of C6 or higher alkyl side chains is 10-20; the density of the hyperbranched polyethylene is 0.85-0.89 g / cm 3 ; Hyperbranched polyethylene is obtained by solution polymerization of ethylene using the following catalysts: Among them, R 1 , R 2 , R 3 , R 4 , R 5 , R 6 and R 7 are independently selected from hydrogen, halogen, nitro, C1-C 10 Straight or branched alkyl and C1-C 10 One of the straight-chain or branched alkoxy groups; Among them, when R 3 When it is hydrogen, R 1 and R 5 Not simultaneously methyl, ethyl or isopropyl; When R 3 When it is methyl, R 1 and R 5 Not simultaneously methyl or ethyl; X 1 and X 2 Each independently selected from one of F, Cl, Br and I; Based on 100 parts by weight of the polymer matrix, the polymer matrix comprises 50-100 parts by weight of the hyperbranched polyethylene and 0-50 parts by weight of the copolymer of ethylene and α-olefin.

6. The method according to claim 5, wherein: The constant temperature standing temperature is 35-60°C, the constant temperature standing time is 1.5-5h, and the extrusion temperature is 70-120°C.

7. The method according to claim 5, wherein: The constant temperature standing temperature is 40-55°C, the constant temperature standing time is 2-4h, and the extrusion temperature is 80-100°C.

8. The method according to claim 4, wherein: The number average molecular weight of the hyperbranched polyethylene is 20,000-250,000 g / mol.

9. The method according to claim 4, wherein: The number average molecular weight of the hyperbranched polyethylene is 20,000-100,000 g / mol.

10. The method according to claim 4, wherein: The hyperbranched polyethylene has a melt flow rate of 0.4-8 g / 10 min at 120° C. and a load of 2.16 kg.

11. The method according to claim 4, wherein: The hyperbranched polyethylene has a melt flow rate of 0.5-6 g / 10 min at 120° C. and a load of 2.16 kg.

12. The method according to any one of claims 5 to 11, wherein: The α-olefin in the copolymer of ethylene and α-olefin is at least one selected from 1-butene, 1-hexene, 1-octene, 1-decene and 1-dodecene.

13. The method according to any one of claims 5 to 11, wherein: The ethylene and α-olefin copolymer is an ethylene-octene copolymer and / or an ethylene-butene copolymer; The number average molecular weight of the ethylene and α-olefin copolymer is 25,000-40,000 g / mol; The α-olefin content in the ethylene and α-olefin copolymer is not less than 20%.

14. The method according to any one of claims 5 to 11, wherein: The auxiliary agent includes at least one of a cross-linking agent, a co-cross-linking agent, a tackifier, an antioxidant and an ultraviolet light absorber; Based on 100 parts by weight of the polymer matrix, the weight portion of the crosslinking agent is 0.3-3 parts; Based on 100 parts by weight of the polymer matrix, the weight portion of the auxiliary cross-linking agent is 0.3-3 parts; Based on 100 parts by weight of the polymer matrix, the weight portion of the tackifier is 0.3-3 parts; Based on 100 parts by weight of the polymer matrix, the weight portion of the antioxidant is 0.1-3 parts; Based on 100 parts by weight of the polymer matrix, the weight of the ultraviolet light absorber is 0.1-3 parts; The cross-linking agent is selected from at least one of tert-butyl peroxy-2-ethylhexyl carbonate, tert-amyl peroxy (2-ethylhexyl) carbonate, 2,5-di-tert-butyl peroxy-2,5-dimethylhexane, tert-butyl peroxymaleate, tert-butyl peroxyisopropyl carbonate, tert-butyl peroxyacetate and 4,4-bis (tert-butyl peroxy) butyl valerate; The auxiliary cross-linking agent is selected from at least one of triallyl isocyanurate, trimethylolpropane trimethacrylate, trimethallyl isocyanate and triallyl cyanurate; The tackifier is selected from at least one of 3-aminopropyltriethoxysilane, γ-glycidyloxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane and vinyltriacetoxysilane; The antioxidant is selected from at least one of tris[2,4-di-tert-butylphenyl]phosphite, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 2,2'-methylenebis(4-methyl-6-tert-butylphenol) and distearyl pentaerythritol diphosphite; The ultraviolet light absorber is selected from at least one of 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-hydroxy-4-n-octyloxybenzophenone, poly(4-hydroxy-2,2,6,6-tetramethyl-1-piperidinylethanol) succinate and bis(2,2,6,6-tetramethylpiperidinyl) sebacate.

15. The method according to claim 14, wherein: Based on 100 parts by weight of the polymer matrix, the weight portion of the crosslinking agent is 0.5-2 parts; Based on 100 parts by weight of the polymer matrix, the weight portion of the auxiliary cross-linking agent is 0.5-2 parts; Based on 100 parts by weight of the polymer matrix, the weight portion of the tackifier is 0.5-2 parts; Based on 100 parts by weight of the polymer matrix, the weight portion of the antioxidant is 0.1-2 parts; Based on 100 parts by weight of the polymer matrix, the weight portion of the ultraviolet light absorber is 0.1-2 parts.

16. A packaging material obtained by the method according to any one of claims 5 to 15.

17. An electronic device assembly, comprising the packaging material according to any one of claims 1 to 4 and 16; the electronic device assembly is a photovoltaic assembly.

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