TW202037679A - Resin pellet - Google Patents

Abstract

Provided is a resin pellet which has a core-sheath structure containing at least two different thermoplastic resins and satisfying specific conditions, thereby preventing blocking or bleeding between pellets even for a long period of storage and exhibiting excellent flowability. This resin pellet has a core-sheath structure containing a thermoplastic resin (A) and a thermoplastic resin (B), wherein: the weight average molecular weight Mw(A) of the thermoplastic resin (A) is 85,000-130,000; the ratio of the weight average molecular weight Mw(A) of the thermoplastic resin (A) to the weight average molecular weight Mw(B) of the thermoplastic resin (B) is 1-4 (exclusive of 1); a sheath part contains the thermoplastic resin (B); a core part contains the thermoplastic resin (A); and a proportion of the thermoplastic resin (A) is greater in the core part than in the sheath part.

Description

Resin pellets

The present invention relates to a resin composition containing a variety of thermoplastic resins and having a core-sheath structure.

Thermoplastic resin (hot-melt resin) is widely used as a molding material, and it can be sealed by lowering its viscosity only by heating and melting. In addition, it has the following excellent characteristics: after sealing, it is solidified by only cooling to form a sealed body, so the productivity is also high, and the resin is melted and removed by heating after the end of the product life, and the component can be easily removed Recycling. Thermoplastic resin (hot-melt resin) has excellent adhesion, insulation, chemical resistance, and molding fluidity, so it is widely used as a sealing material for power electronic parts in automobiles and electrochemical products, as well as equipment used in the medical field. The sealing material of the part.

The thermoplastic resin (hot-melt resin) used as a molding and sealing material is generally in the shape of a cylindrical pellet. In order to improve the fluidity and adhesion during molding, low-melting materials are often blended. Therefore, when supplying the molding machine, the pellets stick to each other due to their high adhesiveness, which makes it difficult to supply materials.

Patent Document 1 discloses a thermoplastic polyester resin pellet by arranging a material with a low melting point that is prone to adhesion in the core (inside) of the core-sheath structure pellet, and has a high melting point and is not prone to adhesion. The material is arranged in the sheath (outside) of the core-sheath structure pellets to inhibit adhesion. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] JP 2001-9833 A

[The problem to be solved by the invention]

However, the invention described in Patent Document 1 can temporarily inhibit blocking, but when stored at high temperatures for a long time, the low melting point material located in the core (inside) of the pellet will ooze out, and the long-term blocking resistance will decrease. The problem.

The present invention is made on the background of the subject of such conventional technology. That is, the object of the present invention is to provide a resin pellet that does not impair the fluidity during molding and has excellent exudation and long-term blocking resistance even after long-term storage at high temperatures. [Means to solve the problem]

The inventors of the present case studied diligently, and as a result, found that the above-mentioned problems can be solved by the means shown below and completed the present invention. That is, the present invention is composed of the following configurations.

A resin pellet containing a thermoplastic resin (A) and a thermoplastic resin (B). The weight average molecular weight Mw (A) of the thermoplastic resin (A) is 85,000 to 130,000, and the weight average molecular weight Mw (A) of the thermoplastic resin (A) The ratio Mw(A)/Mw(B) to the weight average molecular weight Mw(B) of the thermoplastic resin (B) is more than 1 and less than 4, and the thermoplastic resin (B) is contained in the sheath and contained in the core The thermoplastic resin (A) and the ratio of the thermoplastic resin (A) are more core-sheath structures in the core part than in the sheath part.

The ratio W(A)/W(B) of the mass fraction W(A) of the thermoplastic resin (A) to the mass fraction W(B) of the thermoplastic resin (B) is preferably 0.05 to 1. In addition, the melting point of the thermoplastic resin (A) and the melting point of the thermoplastic resin (B) are preferably 100°C or higher, and the difference between the melting point of the thermoplastic resin (A) and the melting point of the thermoplastic resin (B) is preferably 30°C or less.

The core/sheath ratio (mass ratio) of the resin pellets is preferably 50/50~95/5.

It is the above-mentioned resin pellet used for hot-melt sealing material. [Effects of Invention]

The resin pellets of the present invention contain two or more different thermoplastic resins and have a core-sheath structure that meets specific requirements. It maintains adhesiveness and has good exudation even after long-term storage. The pellets do not adhere to each other. And the liquidity is good.

In the present invention, by using a thermoplastic resin (A) with high molecular weight and good adhesiveness, it also contains a thermoplastic resin (B) with low molecular weight and not easy to adhere in the sheath, so as to maintain the adhesiveness of the pellet as a whole. Exudation and blocking resistance are still excellent. The present invention will be described in detail below.

＜Thermoplastic resin (A) and thermoplastic resin (B)＞ The thermoplastic resin (A) and thermoplastic resin (B) of the present invention are not particularly limited, and examples thereof include polyester resins, polyurethane resins, polyamide resins, polyolefin resins, polyamide imide resins, or The polyimide resin may be used alone or in combination of two or more kinds. The thermoplastic resin (A) and the thermoplastic resin (B) may each be the same type of resin, or may be different types of resin. In the case of the same type of resin, it is preferable that the respective compositions or physical properties are different. From the viewpoint of good fluidity, chemical resistance, and long-term reliability of sealing performance, it is desirable that either the thermoplastic resin (A) or the thermoplastic resin (B) is a polyester resin, and the thermoplastic resin (A) and It is more desirable that both the thermoplastic resin (B) are polyester resins, and it is more desirable that both the thermoplastic resin (A) and the thermoplastic resin (B) are crystalline polyester resins.

It is necessary that the weight average molecular weight Mw (A) of the thermoplastic resin (A) is 85,000 or more. It is preferably above 90,000, more preferably above 95,000, and even more preferably above 100,000. And below 130,000 is necessary, preferably below 125,000, more preferably below 120,000, and even more preferably below 115,000. By falling within the above range, an excellent effect of suppressing exudation can be exhibited.

The weight average molecular weight Mw(B) of the thermoplastic resin (B) is preferably 40,000 or more, more preferably 45,000 or more, and even more preferably 50,000 or more. And it should be less than 85,000, more preferably less than 85,000, more preferably less than 80,000, and even more preferably less than 75,000. By falling within the above range, an excellent effect of fluidity during molding can be exhibited while suppressing bleeding.

It is necessary that the ratio Mw(A)/Mw(B) of the weight average molecular weight Mw(A) of the thermoplastic resin (A) to the weight average molecular weight Mw(B) of the thermoplastic resin (B) exceeds 1 and is 4 or less. It is preferably 1.1 or more, more preferably 1.2 or more, and even more preferably 1.4 or more. And it is preferably 3.5 or less, more preferably 3 or less, even more preferably 2.5 or less. By falling within the above range, an excellent effect of fluidity during molding can be exhibited while suppressing bleeding. The weight average molecular weight Mw (A) of the thermoplastic resin (A) and the weight average molecular weight Mw (B) of the thermoplastic resin (B) can be measured by GPC.

The ratio W(A)/W(B) of the mass fraction W(A) of the thermoplastic resin (A) to the mass fraction W(B) of the thermoplastic resin (B) is preferably 0.05~1. It is more preferably 0.1 or more, and even more preferably 0.3 or more. Moreover, it is preferably 0.8 or less, and more preferably 0.6 or less. By falling within the above range, an excellent effect of fluidity during molding can be exhibited while suppressing bleeding.

The melting points of the thermoplastic resin (A) and the thermoplastic resin (B) are preferably 100°C or higher. Above 110°C is more ideal, and above 120°C is even more ideal. In addition, it is more preferably below 200°C, more preferably below 180°C, and even more preferably below 160°C. By falling within the above range, an excellent effect of blocking resistance can be exhibited.

The difference between the melting point of the thermoplastic resin (A) and the melting point of the thermoplastic resin (B) is preferably 30°C or less. It is more ideal below 25°C, and even more ideal below 20°C. In addition, it is more preferably 1°C or higher, more preferably 5°C or higher, and even more preferably 10°C or higher. By falling within the above range, excellent effects of blocking resistance and suppression of bleeding can be exhibited. In terms of melting point, the thermoplastic resin (B) is preferably lower than the thermoplastic resin (A).

Hereinafter, the types of thermoplastic resin (A) and/or thermoplastic resin (B) will be described.

＜Crystalline polyester resin＞ The crystalline polyester resin that can be used in the present invention is a resin having more than one ester bond per repeating unit. For the crystalline polyester resin, it is preferable to use a polycarboxylic acid component and a polyol component as a copolymer component system. Regarding all the polyvalent carboxylic acid components of the crystalline polyester resin, it is preferable to contain terephthalic acid or 2,6-naphthalenedicarboxylic acid from the viewpoint of improving crystallinity.

Regarding all the polyol components of the crystalline polyester resin, from the viewpoints of crystallinity, blocking resistance, and fluidity, a system containing 1,4-butanediol components is preferable.

As for other polyvalent carboxylic acid components, dicarboxylic acid components other than terephthalic acid or 2,6-naphthalenedicarboxylic acid, and trivalent or higher polyvalent carboxylic acid components can be copolymerized. As for the dicarboxylic acid component, for example, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, isophthalic acid, phthalic acid, Aromatic dicarboxylic acids such as diphenoxyethane dicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, 4,4'-diphenyl ketone dicarboxylic acid; adipic acid, sebacic acid, Aliphatic dicarboxylic acids such as succinic acid, dimer acid, and glutaric acid; hexahydroterephthalic acid, hexahydroisophthalic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid Alicyclic dicarboxylic acids such as carboxylic acid and 1,4-cyclohexanedicarboxylic acid, etc. Among them, terephthalic acid is preferable from the viewpoint of polymerizability, cost, and crystallinity. In addition, as for the trivalent or higher polycarboxylic acid component, polycarboxylic acids such as trimellitic acid, pyromellitic acid, benzophenone tetracarboxylic acid, biphenyl tetracarboxylic acid, biphenyl tetracarboxylic acid, etc. And its anhydrides. These dicarboxylic acid components and trivalent or more polyvalent carboxylic acid components can be used alone or in combination of two or more kinds. When the copolymerization ratio of these polycarboxylic acid components is 100 mol% based on all the polycarboxylic acid components of the crystalline polyester resin, it is preferably 5 mol% or less, and more preferably 2 mol% or less. Less than 1 mol% is more ideal, even if 0 mol% is fine.

Regarding other polyol components, diol components other than the above-mentioned 1,4-butanediol component and polyol components having a valence of three or more may be copolymerized. As for other glycol components, for example, ethylene glycol, diethylene glycol, propylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 2,3-butane Diol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 2-methyl-1,5-pentanediol, 2-methyl- 1,3-propanediol, 2-ethyl-1,3-propanediol, neopentyl glycol, 2-ethyl-2-methyl-1,3-propanediol, 2,2-diethyl-1,3- Propylene glycol, 2-methyl-2-n-butyl-1,3-propanediol, 2-n-butyl-2-ethyl-1,3-propanediol, 2,2-di-n-butyl-1,3- Propylene glycol, 2-ethyl-2-n-hexyl-1,3-propanediol, 2,2-di-n-hexyl-1,3-propanediol, 1,9-nonanediol, 1,10-decanediol, 1 ,12-Dodecanediol and other aliphatic diols; Hydroquinone, 4,4'-dihydroxybisphenol, 1,4-bis(β-hydroxyethoxy)benzene, 1,4-bis( β-Hydroxyethoxyphenyl) ash, bis(p-hydroxyphenyl) ether, bis(p-hydroxyphenyl) ash, bis(p-hydroxyphenyl)methane, 1,2-bis(p-hydroxyphenyl)ethyl Aromatic diols such as alkanes, bisphenol A, and alkylene oxide adducts of bisphenol A; 1,2-cyclohexanediol, 1,3-cyclohexanediol, and cis 1,4-cyclohexanediol , 1,2-cyclohexane dimethanol, 1,3-cyclohexane dimethanol, 1,4-cyclohexane dimethanol, 1,4-cyclohexane diethanol and other alicyclic diols. Moreover, as for the polyhydric alcohol component with a trivalent or higher valence, for example, trimethylolethane, trimethylolpropane, glycerin, neopentylerythritol, etc. can be mentioned. These diol components and trivalent or higher polyol components can be used alone or in combination of two or more kinds. When the copolymerization ratio of these polyol components is 100 mol% based on all the polyol components of the crystalline polyester resin, it is preferably 5 mol% or less, more preferably 2 mol%, and 1 mol%. Ear% or less is more ideal, even if 0 mole% is no problem.

In addition, 5-sulfoisophthalic acid, 4-sulfonaphthalene-2,7-dicarboxylic acid, 5-sulfoisophthalic acid, 4-sulfonaphthalene-2,7-dicarboxylic acid, 5-[4-sulfophenoxy]isophthalic acid, its alkali metal salt, or 2-sulfo-1,4-butanediol, 2,5-dimethyl-3-sulfonic acid -2,5-Hexanediol, its metal salt, etc. containing dicarboxylic acid component or glycol component containing sulfonic acid metal salt group.

Regarding the polyol component of the crystalline polyester resin, there is no problem in copolymerizing the polyalkylene glycol ether component. Examples of the polyalkylene glycol ether component include triethylene glycol, polyethylene glycol, polytrimethylene glycol, polytetramethylene glycol (PTMG), polypropylene glycol, and the like.

In the present invention, the term “crystallinity” refers to a temperature rise from -130°C to 250°C at 20°C/min using a differential scanning calorimeter (DSC), and a clear melting peak is shown during the temperature rise process. If the polyester resin has crystallinity, it can be expected to have better heat resistance and better mechanical properties.

The catalyst used in the production of the copolymerized polyester resin is not particularly limited, and it is preferable to use at least one compound system selected from the group consisting of Ge, Sb, Ti, Al, Mn, or Mg. These compounds are added to the reaction system in the form of powder, aqueous solution, ethylene glycol solution, ethylene glycol slurry, and the like.

In addition, a stabilizer for a crystalline polyester resin may be blended in a range that does not impair the effect of the invention of the present application. As for the stabilizer, use is selected from phosphoric acid, polyphosphoric acid, trimethyl phosphate and other phosphoric acid esters, phosphonic acid compounds, phosphinic acid compounds, phosphine oxide compounds, phosphinic acid compounds, and phosphinic acid compounds. Phosphonic acid compounds and at least one phosphorus compound from the group consisting of phosphine compounds are preferable.

When the resin composition of the present invention is exposed to a high temperature and high humidity environment for a long time, it is desirable to add an antioxidant system within a range that does not impair the effects of the present invention. For preferred antioxidants, for example, hindered phenolic 1,3,5-ginseng (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 1,1 ,3-Tris(4-hydroxy-2-methyl-5-tert-butylphenyl)butane, 1,1-bis(3-tert-butyl-6-methyl-4-hydroxyphenyl) Butane, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-phenylpropionic acid, pentaerythritol 4 (3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid Ester, 3-(1,1-dimethylethyl)-4-hydroxy-5-methyl-phenylpropionic acid, 3,9-bis[1,1-dimethyl-2-[(3-第Tributyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane, 1,3,5-tri Methyl-2,4,6-ginseng (3',5'-di-tert-butyl-4'-hydroxybenzyl)benzene; phosphorus-based 3,9-bis(p-nonylphenoxy)- 2,4,8,10-Tetraoxa-3,9-Diphosphospiro[5.5]undecane, 3,9-bis(octadecyloxy)-2,4,8,10-Tetraoxa -3,9-Diphosphospirocyclo[5.5]undecane, tris(monononylphenyl) phosphite, triphenoxyphosphine, isodecyl phosphite, isodecyl phenyl phosphite, Diphenyl 2-ethylhexyl phosphite, dinonylphenyl bis(nonylphenyl) phosphoric acid, 1,1,3-ginseng (2-methyl-4-bistridecyl phosphite) -5-tert-butylphenyl)butane, ginseng (2,4-di-tert-butylphenyl) phosphite, neopentylerythritol bis(2,4-di-tert-butylphenyl) Phosphite), 2,2'-methylene bis(4,6-di-tert-butylphenyl) 2-ethylhexyl phosphite, bis(2,6-di-tert-butyl- 4-methylphenyl) neopentylerythritol diphosphite; thioether series of 4,4'-thiobis[2-tertiarybutyl-5-methylphenol]bis[3-(twelve Alkylthio) propionate], thiobis[2-(1,1-dimethylethyl)-5-methyl-4,1-phenylene]bis[3-(tetradecylthio) Yl)-propionate], neopentylerythritol 4 (3-n-dodecylthiopropionate), bis(tridecyl)thiodipropionate, these can be used alone or in combination. The addition amount is preferably 0.1% by weight or more and 5% by weight or less with respect to the entire resin composition. If it is less than 0.1% by weight, the antioxidant effect may be lacking. In addition, if it exceeds 5% by weight, it may adversely affect the adhesion and the like.

When the weather resistance of the resin composition of the present invention is further required, it is preferable to add a light stabilizer. For example, benzotriazole-based light stabilizers include 2-(3,5-di-tertiary pentyl-2' hydroxyphenyl) benzotriazole, 2-(2-hydroxy-5- The third octyl phenyl) benzotriazole, 2-(2'-hydroxy-3'-tertiary butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2H- Benzotriazol-2-yl)-p-cresol, 2-(2'-hydroxy-5'-methylphenyl)-benzotriazole, 2,4-di-tert-butyl-6-( 5-Chlorobenzotriazol-2-yl)phenol, 2-[2-hydroxy-3,5-bis(1,1-dimethylbenzyl)]-2H-benzotriazole, etc., but not limited to These can be suitably used as long as they are benzotriazole-based light stabilizers. As for the benzophenone-based light stabilizer, for example, 2-hydroxy-4-(octyloxy) benzophenone, 2,4-dihydroxy benzophenone, 2-hydroxy-4-methyl Oxybenzophenone, 2-hydroxy-4-methoxy-benzophenone-5-sulfonic acid, 2-hydroxy-4-n-dodecyloxybenzophenone, bis(5-benzyl Aceto-4-hydroxy-2-methoxyphenyl)methane, 2,2'-dihydroxy-4-methoxydiphenyl ketone, 2,2'-dihydroxy-4,4'-dimethyl Oxybenzophenone etc., but it is not limited to these, As long as it is a benzophenone type light stabilizer, it can use suitably. As for hindered amine light stabilizers, for example, bis(2,2,6,6-tetramethyl-4-piperidinyl)sebacic acid, dimethyl succinate and 1-(2-hydroxyethyl) Yl)-4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate, poly[{6-(1,1,3,3-tetramethylbutyl)amino-1,3 ,5-Tris 𠯤-2,4-diyl}{(2,2,6,6-tetramethyl-4-piperidinyl)imino group} hexamethylene (2,2,6,6- Tetramethyl-4-piperidinyl)imino], 1,3,5-ginseng (3,5-di-tert-butyl-4-hydroxybenzyl)-s-tris-2,4, 6(1H,3H,5H) triketone, ginseng (4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)-s-tris-2,4,6-(1H,3H ,5H) Triketones, etc., but are not limited to these, as long as they are hindered amine light stabilizers, they can be suitably used. For nickel-based light stabilizers, examples include [2,2'-sulfanyl-bis(4-tertiary octylphenol ester)]-2-ethylhexylamine-nickel-(II), dibutyl Nickel dithiocarbamate, [2',2'-thio-bis(4-tertiary octylphenol ester)] n-butylamine-nickel, etc., but not limited to these, as long as it is a nickel-based light stabilizer Can be used appropriately. As for the benzoate-based light stabilizer, for example, 2,4-di-tert-butylphenyl-3,5'-di-tert-butyl-4'-hydroxybenzoate, etc., However, it is not limited to these, as long as it is a benzoate type light stabilizer, it can use suitably. These light stabilizers can be used alone or in combination. The addition amount is preferably 0.1% by weight or more and 5% by weight or less based on the entire resin composition. If it is less than 0.1% by weight, the weather resistance effect may be lacking. If it exceeds 5% by weight, it may have an adverse effect on adhesion and the like.

In addition, in the resin composition of the present invention, various known additives can be used within a range that does not impair the effects of the present invention. Examples of additives include impact modifiers, sliding properties modifiers, colorants, plasticizers, crystal nucleating agents, and thermoplastic resins other than polyester.

As far as the acid value of the crystalline polyester resin is concerned, it is preferably 1-40 eq/ton, more preferably 2-30 eq/ton, and even more preferably 3-20 eq/ton. If the acid value exceeds 40eq/ton, the light resistance tends to decrease. In addition, when the acid value is less than 1 eq/ton, the polycondensation reactivity is lowered and productivity tends to be poor.

The glass transition temperature of the crystalline polyester resin is preferably -60°C or higher, more preferably -50°C or higher, and even more preferably -40°C or higher. If it is too low, the mechanical properties at high temperatures and the strength of the resin may decrease. Furthermore, it is preferably 10°C or less, more preferably 0°C or less, and even more preferably -10°C or less. If it is too high, it may cause a decrease in mechanical properties in a low temperature environment below the glass transition temperature.

＜Polyurethane resin＞ The polyurethane resin that can be used in the present invention is a resin having more than one urethane bond per repeating unit. The polyurethane resin is preferably a resin obtained by addition polymerization of a polyol having a diol as the main body and a polyisocyanate having a diisocyanate as the main body.

For the polyols used in the manufacture of polyurethane resins, examples include low molecular weight polyols, polyester polyols, polyether polyols, and polycarbonates used in the manufacture of the above-mentioned polyester resins. For high molecular weight polyols such as polyols, one or two or more of them can be used in combination. Among them, polyester polyols are preferable from the viewpoint of fluidity, adhesion, and long-term reliability of sealing performance.

For the polyisocyanates used in the manufacture of polyurethane resins, aromatic polyisocyanates, aliphatic polyisocyanates, or alicyclic polyisocyanates can be used. Among them, aromatic diisocyanates are used as the main body. ideal. In terms of the main body, when all the polyisocyanates are set to 100 mol%, the aromatic diisocyanate containing 60 mol% or more is ideal, 80 mol% or more is more ideal, and 90 mol% or more is more ideal. Ideal, 100 mol% is fine.

As for the aromatic diisocyanate component, specific examples include diphenylmethane-2,4'-diisocyanate, 3,2'- or 3,3'- or 4,2'- or 4,3'- or 5,2'- or 5,3'- or 6,2'- or 6,3'-dimethyldiphenylmethane-2,4'-diisocyanate, 3,2'- or 3,3'- Or 4,2'-or 4,3'-or 5,2'-or 5,3'-or 6,2'-or 6,3'-diethyldiphenylmethane-2,4'-di Isocyanate, 3,2'-or 3,3'-or 4,2'-or 4,3'-or 5,2'-or 5,3'-or 6,2'-or 6,3'-di Methoxydiphenylmethane-2,4'-diisocyanate, diphenylmethane-4,4'-diisocyanate, diphenylmethane-3,3'-diisocyanate, diphenylmethane-3,4 '-Diisocyanate, diphenyl ether-4,4'-diisocyanate, diphenyl ketone-4,4'-diisocyanate, diphenylene-4,4'-diisocyanate, tolylene-2 ,4-Diisocyanate, phenylmethylene-2,6-diisocyanate, m-xylene diisocyanate, p-xylene diisocyanate, naphthalene-2,6-diisocyanate, 4,4'-[2,2bis( 4-phenoxyphenyl)propane)diisocyanate, 3,3'-or 2,2'-dimethylbiphenyl-4,4'-diisocyanate, 3,3'-or 2,2'-diisocyanate Ethyl biphenyl-4,4'-diisocyanate, 3,3'-dimethoxybiphenyl-4,4'-diisocyanate, 3,3'-diethoxybiphenyl-4,4'- Diisocyanate, etc.

For the aliphatic diisocyanate component, for example, hexamethylene diisocyanate, lysine diisocyanate, etc.; for the alicyclic diisocyanate component, for example, isophorone diisocyanate, dicyclohexylmethane diisocyanate, reverse Formula cyclohexane-1,4-diisocyanate, etc. Among them, from the viewpoint of fluidity, adhesiveness, and long-term reliability of sealing performance, aliphatic diisocyanate or aromatic diisocyanate series are preferable, and aliphatic diisocyanate series are more preferable. Among them, hexamethylene diisocyanate is particularly desirable.

In the production of polyurethane, a chain extender can also be used if necessary. As for chain extenders, examples include low molecular weight polyols, dimethylol propionic acid, dimethylol butyric acid, etc., which are used in the synthesis of the above-mentioned polyester resins as glycol components. Molecular weight of glycols, etc. Among them, the use of dimethylolbutyric acid and trimethylolpropane is ideal for the purpose of improving the fluidity, adhesiveness, and long-term reliability of the sealing performance of the polyurethane resin.

Regarding the manufacturing method of the polyurethane resin, the polyol and the polyisocyanate and optionally the chain extender can be charged into the reaction vessel at once, or divided and charged. In any case, in terms of the sum of the hydroxyl valences of the polyol in the system, the chain extender if necessary, and the sum of the isocyanate groups of the polyisocyanate, a reaction system with an isocyanate group/hydroxyl functional group ratio of 1 or less is preferable. In addition, this reaction can be produced by reacting in the presence or absence of an organic solvent which is inactive to isocyanate groups. The organic solvents include, for example, ester solvents (ethyl acetate, butyl acetate, ethyl butyrate, etc.), ether solvents (dioxane, tetrahydrofuran, diethyl ether, etc.), ketone solvents (cyclohexane, etc.) Ketone, methyl ethyl ketone, methyl isobutyl ketone, etc.), aromatic hydrocarbon solvents (benzene, toluene, xylene, etc.), and mixed solvents thereof. From the viewpoint of price reduction and environmental impact, ethyl acetate and methyl ethyl ketone are preferable. The solid content concentration of the polyurethane resin solution is preferably 30-60% by mass, more preferably 40-50% by mass.

＜Polyamide resin＞ The polyamide resin that can be used in the present invention is a resin having more than one amide bond per repeating unit. The polyamide resin is preferably synthesized by the chlorination method using polycarboxylic acid chloride and diamine, the melt polymerization method using polycarboxylic acid and diamine, or the solution polymerization method using polycarboxylic acid and diisocyanate.

As the polycarboxylic acid component used in the synthesis of the polyamide resin, aromatic, aliphatic, or alicyclic dicarboxylic acids and trifunctional or higher carboxylic acids used in the synthesis of the polyester resin can be used. Among them, from the viewpoint of fluidity, adhesiveness, and long-term reliability of sealing performance, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, sebacic acid, or azela The acid system is ideal. When further flexibility is required, dimer acid, dicarboxylic acid polybutadiene with a molecular weight of 1000 or more, dicarboxylic acid poly(acrylonitrile butadiene), dicarboxylic acid Acid-based poly(styrene-butadiene) is copolymerized.

In the present invention, the diamine component used when synthesizing polyamide resin by the melt polymerization method includes aliphatic diamines such as ethylenediamine, propylenediamine, and hexamethylenediamine; piperidine, 1,4 -Alicyclic diamines such as cyclohexanediamine, 1,3-cyclohexanediamine, and dicyclohexylmethyldiamine; m-phenylenediamine, p-phenylenediamine, 4,4'-diaminodiphenyl Aromatic diamines such as methyl methane, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, benzidine, xylene diamine, naphthalene diamine, etc. Among these, from the viewpoint of fluidity, adhesiveness, and long-term reliability of sealing performance, isophorone diamine and dicyclohexyl methyl diamine are preferred, and diamino diphenyl methane is part of them. The copolymerization system of toluene diamine is also ideal.

When the polyamide resin is synthesized by the melt polymerization method, salts can be formed from the aforementioned dicarboxylic acid and diamine, and they can be synthesized by a general method such as condensation while heating and stirring under pressure.

When synthesizing polyamide resin by solution polymerization, you can use polar solvents such as N, n-dimethylformamide, N, n-dimethylacetamide, n-methyl-2-pyrrolidone, and γ-butyrolactone. The above-mentioned dicarboxylic acid and diisocyanate are dissolved in a solid content concentration of 30 to 60% by mass, and they are stirred while heating at 60 to 200°C for synthesis. In this case, if necessary, amines such as triethylamine and diethylenetriamine; alkali metal salts such as sodium fluoride, potassium fluoride, cesium fluoride, and sodium methoxide can also be used as a catalyst. At this time, as for the diisocyanate, the diisocyanate used in the synthesis of the above-mentioned polyurethane resin can be used. Among them, from the viewpoint of fluidity, adhesiveness, and long-term reliability of sealing performance, different Phosphonone diisocyanate and dicyclohexylmethane diisocyanate are preferable, and part of it is replaced by diphenylmethane-4,4'-diisocyanate and toluene diisocyanate.

The glass transition temperature of polyamide resin is preferably above 30°C, more preferably above 70°C, and even more preferably above 100°C. If the glass transition temperature is less than 30°C, heat resistance may be insufficient. The upper limit is not particularly limited, but is preferably 200°C or lower, and more preferably 160°C or lower.

＜Polyolefin resin＞ The polyolefin resin that can be used in the present invention is not limited, and is preferably an unmodified polyolefin resin. In addition, an acid-modified polyolefin obtained by grafting at least one of α,β-unsaturated carboxylic acid and its anhydride onto an unmodified polyolefin resin is also ideal. The so-called polyolefin resin refers to the homopolymerization of olefin monomers such as ethylene, propylene, butene, butadiene, isoprene, etc., or copolymerization with other monomers, and the hydrogenated product of the resulting polymer , Halides and other polymers with hydrocarbon skeleton as the main body. That is, the acid-modified polyolefin is prepared by adding at least one of α, β-unsaturated carboxylic acid and its anhydride in at least one of polyethylene, polypropylene, and propylene-α-olefin copolymer Those who are grafted are ideal.

The propylene-α-olefin copolymer is made by copolymerizing α-olefin with propylene as the main body. For α-olefins, for example, one or more of ethylene, 1-butene, 1-heptene, 1-octene, 4-methyl-1-pentene, vinyl acetate, etc. can be used. Among these α-olefins, ethylene and 1-butene are particularly preferred. The ratio between the propylene component and the α-olefin component of the propylene-α-olefin copolymer is not limited, and the propylene component is preferably at least 50 mol%, and more preferably at least 70 mol%.

As for at least one of α,β-unsaturated carboxylic acids and their anhydrides, for example, maleic acid, itaconic acid, citraconic acid, and their anhydrides can be mentioned. Among these, acid anhydride is particularly desirable, and maleic anhydride is more desirable. Specific examples include maleic anhydride modified polyolefin, maleic anhydride modified propylene-ethylene copolymer, maleic anhydride modified propylene-butene copolymer, maleic anhydride modified propylene-ethylene-butene copolymer, etc. One type or two or more types of these polyolefin resins can be used in combination.

As for the production method of polyolefin resin, it is not particularly limited. Examples include free radical grafting reaction (that is, generating radical species for the polymer that becomes the main chain, and using the radical species as the polymerization starting point. Graft polymerization with unsaturated carboxylic acid and acid anhydride).

The radical initiator is not particularly limited, but it is preferable to use an organic peroxide. Organic peroxides are not particularly limited, and examples include di-tert-butylperoxyphthalate, tert-butanol peroxide, diisopropylbenzene peroxide, benzyl peroxide, peroxy Oxidized tert-butyl benzoate, tert-butyl peroxide-2-ethylhexanoic acid, tert-butyl tert-amyl peroxide, methyl ethyl ketone peroxide, di-tert-butyl peroxide, lauryl Peroxides such as peroxides; azo nitriles such as azobisisobutyronitrile and azobisisopropionitrile.

＜Polyamide imide resin＞ The polyimide imine resins that can be used in the present invention are resins containing more than one amide bond and amide bond per repeating unit, and it is preferable that each repeating unit has more than two amide bond. The polyamide resin can also be a polyamide resin synthesized from a polyamide acid synthesized from a trifunctional or higher polycarboxylic acid anhydride and a diamine, or it can be directly synthesized from a diisocyanate Any of the obtained polyimide imine resins. When using a polyamide resin, it is usually necessary to complete the imidization reaction system at a temperature of 300°C or higher. On the other hand, when a method of directly synthesizing a polyimide imide resin from a carboxylic acid anhydride having a trifunctional or more and a diisocyanate is used, it can be synthesized at a temperature of 200°C or less. Therefore, the polyamide imide resin used in the present invention is preferably synthesized from diisocyanate. The polyamide imide resin synthesized by the diisocyanate method is synthesized from trimellitic anhydride and diisocyanate as the main acid components. The amide bond and the imine bond in the molecule alternately repeat to form a polymer. ideal.

As for the acid component used in the synthesis of polyamideimide resin, it is preferable to use trimellitic anhydride as the trifunctional carboxylic acid anhydride. In addition, a part of trimellitic anhydride may be substituted with tetrafunctional carboxylic anhydride or dicarboxylic acid. As for tetrafunctional carboxylic acid anhydrides, aromatic acid anhydrides and alicyclic acid anhydrides can be mentioned, for example. For example, with regard to aromatic acid anhydrides, examples include pyromellitic acid dianhydride, 3,3',4,4'-diphenyl ketone tetracarboxylic dianhydride, 3,3',4,4'-linked Pyromellitic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,5,6-pyridinetetracarboxylic dianhydride Anhydride, 3,4,9,10-perylene tetracarboxylic dianhydride, 3,3',4,4'-diphenyl tetracarboxylic dianhydride, terphenyl-3,3',4,4' -Tetracarboxylic dianhydride, 4,4'-oxydiphthalic dianhydride, 1,1,1,3,3,3-hexafluoro-2,2-bis(2,3-or 3, 4-dicarboxylic acid phenyl) propane dianhydride, 2,2-bis(2,3- or 3,4-dicarboxylic acid phenyl) propane dianhydride, 2,2-bis[4-(2, 3- or 3,4-dicarboxylate phenoxy) phenyl] propane dianhydride, 1,1,1,3,3,3-hexafluoro-2,2-bis[4-(2,3- Or 3,4-dicarboxyphenoxy)phenyl)propane dianhydride, 1,3-bis(3,4-dicarboxyphenyl)-1,1,3,3-tetramethyldi Silicone dianhydride, ethylene glycol ditrimellitic anhydride (TMEG), propylene glycol ditrimellitic anhydride, 1,4-butanediol ditrimellitic anhydride, hexanediol ditrimellitic anhydride , Polyethylene glycol ditrimellitic anhydride, polyene glycol ditrimellitic anhydride and other alkylene glycol ditrimellitic anhydride, 2,2-bis[4-(dicarboxylic phenoxy) Yl)phenyl]propane dianhydride, bis[4-(dicarboxyphenoxy)phenyl]sulfuric acid dianhydride, bis[4-(dicarboxyphenoxy)phenyl]methane Anhydride, 4,4'-(4,4'-hexafluoropropylenephenoxy) diphthalic dianhydride, 4,4'-(4,4'-diphenylpropylenephenoxy ) Bisphthalic dianhydride.

For aliphatic polycarboxylic acid anhydrides or alicyclic polycarboxylic acid anhydrides, for example, butane-1,2,3,4-tetracarboxylic dianhydride, pentane-1,2,4,5-tetracarboxylic acid Dianhydride, cyclobutane tetracarboxylic dianhydride, hexahydropyromellitic dianhydride, 1-cyclohexene-2,3,5,6-tetracarboxylic dianhydride, 3-ethyl-1-cyclohexane Ene-3-(1,2),5,6-tetracarboxylic dianhydride, 1-methyl-3-ethylcyclohexane-3-(1,2),5,6-tetracarboxylic dianhydride , 1-Methyl-3-ethyl-1-cyclohexene-3-(1,2), 5,6-tetracarboxylic dianhydride, 1-ethylcyclohexane-1-(1,2) ,3,4-tetracarboxylic dianhydride, 1-propylcyclohexane-1-(2,3), 3,4-tetracarboxylic dianhydride, 1,3-dipropylcyclohexane-1- (2,3),3-(2,3)-tetracarboxylic dianhydride, dicyclohexyl-3,4,3',4'-tetracarboxylic dianhydride, bicyclo[2.2.1]heptane-2 , 3,5,6-tetracarboxylic dianhydride, 1-propylcyclohexane-1-(2,3), 3,4-tetracarboxylic dianhydride, 1,3-dipropylcyclohexane- 1-(2,3),3-(2,3)-tetracarboxylic dianhydride, dicyclohexyl-3,4,3',4'-tetracarboxylic dianhydride, bicyclo[2.2.1]heptane -2,3,5,6-tetracarboxylic dianhydride, bicyclo[2.2.2]octane-2,3,5,6-tetracarboxylic dianhydride, bicyclo[2.2.2]oct-7-ene- 2,3,5,6-tetracarboxylic dianhydride, hexahydro trimellitic anhydride, etc.

In addition, a dicarboxylic acid can be used as a part of trimellitic anhydride. Examples of the dicarboxylic acid include aromatic, aliphatic, or alicyclic dicarboxylic acids used in the production of the above-mentioned polyester resin.

Regarding the diisocyanate used in the synthesis of the polyamide imine resin of the present invention, aromatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates are used. Specific examples include those used in the above polyurethane Diisocyanate in the synthesis of acid ester resin. Among them, aromatic diisocyanates are particularly ideal. From the viewpoint of fluidity, adhesion, and long-term reliability of sealing performance, diphenylmethane-4,4'-diisocyanate, tolylene-2, 4-Diisocyanate, 3,3' or 2,2'-dimethylbiphenyl-4,4'-diisocyanate is ideal, diphenylmethane-4,4'-diisocyanate, tolylene-2 , 4-Diisocyanate is more ideal.

When synthesizing polyamide imine resins by the isocyanate method, N, n-dimethylacetamide, n-methyl-2-pyrrolidone, dimethyl sulfide, cresol, γ-butyrolactone, etc. can be used The solid content concentration in the polar solvent is 20-50% by mass to dissolve acid anhydride and diisocyanate, and potassium fluoride, sodium fluoride, diazabicycloundecene, triethylamine, etc. are added as needed. The medium is synthesized by heating and stirring at 60~200℃ in an inactive environment.

＜Polyimide resin＞ The polyimide resin that can be used in the present invention can also be a polyimide resin obtained from a polyamide acid synthesized from a 4-functional carboxylic acid anhydride and a diamine, or a polyimide resin synthesized directly from a diisocyanate Any of polyimide resins. When using a polyamide resin, it is usually necessary to complete the imidization reaction system at a temperature of 300°C or higher. On the other hand, when a method of directly synthesizing a polyimide resin from a tetravalent carboxylic anhydride and a diisocyanate is used, it can be synthesized at a temperature below 200°C. Therefore, the polyimide resin used in the present invention is preferably synthesized from diisocyanate.

Regarding the tetravalent carboxylic acid anhydride used in the synthesis of polyimide resin, any one of aromatic anhydrides, aliphatic anhydrides, and alicyclic acids used in the synthesis of the above polyimide resin can be used One or more of them can be used in combination.

Moreover, as for the diamine component used when manufacturing polyamide acid, the diamine used for the synthesis of the said polyamide resin can be used. Among them, aromatic diamines such as 4,4'-diaminodiphenylmethane and 4,4'-diaminodiphenyl ether are particularly preferred.

As for the diisocyanate used in the synthesis of the polyimide resin, the aromatic diisocyanate, the aliphatic diisocyanate, or the alicyclic diisocyanate used in the synthesis of the polyimide resin can be used. Among them, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 3,3'-dimethyl-4,4'-diphenyl diisocyanate, or isophorone diisocyanate are more ideal, accounting for all It is preferable that 30 mol% or more of the diisocyanate component contains one or two or more of them.

When synthesizing polyimide resin by the isocyanate method, it is the same as the synthesis of polyimide resin mentioned above by adding tetracarboxylic anhydride, diisocyanate, and a polar solvent such as n-methyl-2-pyrrolidone. If necessary, the catalyst is fed so that the solid content concentration is 20-50% by mass, and it is synthesized by heating and stirring at 60-200°C in an inert gas environment.

＜Core sheath structure＞ The resin pellet of the present invention has a core sheath structure. The so-called core-sheath structure refers to a structure composed of two layers of a core and a sheath. By having a core-sheath structure, it will not agglomerate even if it is stored for a long time, and the handling is good. In the present invention, it is necessary to contain the thermoplastic resin (B) at least in the sheath. The content of the thermoplastic resin (B) in the sheath is preferably 60% by mass or more, more preferably 70% by mass or more, more preferably 80% by mass or more, particularly preferably 90% by mass or more, and most preferably 95% Mass% or more, even if it is 100 mass %. By containing 60% by mass or more of the thermoplastic resin (B) in the sheath, the effect of blocking resistance and excellent fluidity during molding can be exhibited.

It is necessary to contain the thermoplastic resin (A) in the core. The content of the thermoplastic resin (A) in the core is preferably 60% by mass or more and 100% by mass or less, and more preferably 65% by mass or more and 95% by mass or less. Ideally, it is more than 70% by mass and less than 90% by mass. By containing 60% by mass or more of the thermoplastic resin (A) in the core, an excellent effect of suppressing bleeding can be exhibited. The content ratio of the thermoplastic resin (A) is preferably more in the core part than in the sheath part. In addition, it is also desirable to contain the thermoplastic resin (B) in the core. When the thermoplastic resin (B) is contained, its content is preferably 5 mass% or more, more preferably 10 mass% or more, more preferably 40 mass% or less, more preferably 35 mass% or less, and more preferably 30 mass% or less Very ideal. The thermoplastic resin (B) blended in the core part is preferably the same thermoplastic resin (B) as the sheath part.

When two or more types of thermoplastic resins are used in combination in the core or sheath, the weight average molecular weight is the weighted average. For example, when the core contains 60% by mass of a thermoplastic resin (A) with a weight average molecular weight of 100,000 and 40% by mass of a thermoplastic resin (B) with a weight average molecular weight of 69,000, the weight average molecular weight of the core is 87,600 (=100,000×60 Mass% + 69,000×40 mass%). In addition, the melting point is also calculated by the same weighted average.

The ratio of the weight average molecular weight of the core to the sheath (core/sheath) is preferably 1 or more, more preferably 1.1 or more, and more preferably 1.2 or more. Also, 4 or less is more preferable, 3.25 or less is more preferable, and 3 or less is more preferable.

The difference between the melting point of the core and the sheath is preferably below 30°C, more preferably below 20°C, and even more preferably below 10°C.

The ratio of core to sheath between core and sheath (mass ratio of core/sheath) is ideally in the range of 50/50~95/5, more ideal in the range of 55/45~90/10, and in the range of 60/40~85 /15 is even more ideal. By falling within the above range, it can exhibit excellent anti-blocking properties, good flowability during molding, and excellent effects of inhibiting bleeding. The core-sheath structure can be manufactured using a core double-shaft extruder, a sheath single-shaft extruder, and a core-sheath mold.

The resin pellets of the present invention are suitable for sealing materials. Specifically, it is ideal for applications of sealing materials such as electrical electronic substrates, wiring harnesses, and medical catheters.

The method for determining the composition and composition ratio of the thermoplastic resin (A) and the thermoplastic resin (B) includes, for example, ¹ H-NMR and ¹³ C-NMR, which are measured by dissolving the thermoplastic resin in a solvent such as deuterated chloroform . In addition, quantification by gas chromatography measured after methanolysis of thermoplastic resin (hereinafter, sometimes referred to as methanolysis-GC method) is used; the acid value (AV) of thermoplastic resin is measured by The melting point (Tm) and glass transition temperature (Tg) are measured by DSC. In the present invention, when there is a solvent that can dissolve the thermoplastic resin and is suitable for ¹ H-NMR measurement, ¹ H-NMR is used to determine the composition and the composition ratio. When there is no suitable solvent, and when the composition ratio cannot be determined by ¹ H-NMR measurement alone, ¹³ C-NMR, methanolysis-GC method, acid value measurement, melting point measurement by DSC, glass transition temperature measurement are used or combined . [Example]

In order to further describe the present invention in detail, examples and comparative examples are listed below, but the present invention should not be limited by the examples. In addition, each measurement value described in the Example and the comparative example was measured by the following method.

＜Measuring the weight average molecular weight of thermoplastic resin＞ A sample of 0.0050 g of a thermoplastic resin was heated and dissolved in 5 ml of chloroform. After that, it was filtered with a membrane filter to remove insoluble components. 80 μl of the filtrate (sample solution) was measured with GPC "EZChrom Elite for Hitachi" manufactured by Hitachi High-Tech Fielding Co., Ltd. to obtain the weight average molecular weight. Three columns of Shodex GPC K-802, GPC K-804L, and GPC K-806L are used in series, the column temperature is 40℃ (column oven: Hitachi ELITE LaChrom L-2350), the flow rate is 1.0mL/min, The mobile phase is chloroform, and the detector is Hitachi ELITE LaChrom L-2490 RI detector. Prepare a polystyrene solution as a standard material and use it as a sample for GPC calibration curve.

＜Melting point and glass transition temperature measurement＞ Put 5 mg of the measurement sample (thermoplastic resin) into an aluminum pot with a differential scanning calorimeter "DSC220" manufactured by Seiko Instruments Inc., and close the lid to seal it. Then, after briefly maintaining at 250°C for 5 minutes, then rapidly cooling with liquid nitrogen, and then measuring from -130°C to 250°C at a temperature increase rate of 20°C/min. The tangent line (1) obtained from the baseline before the part of the DSC shown as the inflection point in the obtained curve as shown in Figure 1 and the intersection point of the tangent line (2) obtained from the baseline after the inflection point is defined as the glass transition Temperature, and the minimum point of the endothermic peak (mark in the figure) is defined as the melting point.

＜Adhesion test＞ Put 300g of resin pellets with core sheath structure or resin pellets without sheath core structure (single layer) into a 500g disposable cup, and apply a predetermined temperature, load and time to adhere the pellets To confirm. Evaluation criteria (1) 60℃×24 hours×2kg load 〇: No adhesion in 24 hours △: A part (less than about 20%) is stuck in 24 hours ×: Almost all (about 100%) are stuck in 24 hours (2) 25℃×1 week×140kg load 〇: After 1 week, there is no adhesion △: After 1 week, some (about 20% or less) adhesion ×: After 1 week, almost all (less than 100%) have adhesions

＜Exudation test＞ Apply 100 g of resin pellets with a core-sheath structure or resin pellets without a sheath-core structure (single layer) to a predetermined temperature and time, then let it stand, and then check the state of the pellet surface. Evaluation criteria ○: After 6 months, there is no exudation of the resin component of the core and no change in the surface condition △: After 6 months, no resin component of the core part oozes out, and the surface condition changes (discoloration, etc.) ×: After 6 months, the resin component of the core part oozes out, and the surface condition changes

＜Melting characteristics (fluidity) test＞ In a flow tester (CFT-500C type) manufactured by Shimadzu Corporation, the cylinder in the center of the heating body set at 220°C is filled with a single layer containing two or more types of thermoplastic resins that have dried moisture content below 0.1% or Resin pellets with core-sheath structure. After filling for 1 minute, the intervening plunger applies a load to the sample, and the molten sample is extruded through the die (aperture: 1.0mm, thickness: 10mm) at the bottom of the cylinder at a pressure of 1MPa, and the plunger’s descending distance and Decrease time and calculate melt viscosity. Evaluation criteria ◎: 500dPa･s or less (measurement temperature 220℃) ○: Over 500dPa･s, 1000dPa･s or less (measurement temperature 220℃) △: Over 1000dPa･s, 1500dPa･s or less (measurement temperature 220℃) ×: more than 1500dPa･s (measurement temperature 220℃) If the melt viscosity is too high, the fluidity of the power electronic parts during sealing will decrease, insufficient sealing will occur, or high pressure forming will be necessary, which may cause a load on the power electronic parts and cause adverse effects.

Table 1 lists the weight average molecular weight Mw and melting point of the various thermoplastic resins used this time.

[Table 1] Thermoplastic resin Weight average molecular weight (Mw) Melting point (Tm) a Polyester Terephthalic acid-PTMG-butanediol copolymer polyester 100000 160 b Polyester Terephthalic acid-PTMG-butanediol copolymer polyester 69000 160 c Polyester Polyester of naphthalenedicarboxylic acid-PTMG-butanediol copolymer 85000 160 d Polyamide Polyamide of dimer acid-sebacic acid-piperidine ethylene diamine copolymer 130000 130 e Polyamide Polyamide of dimer acid-sebacic acid-piperidine-ethylenediamine copolymer 40000 130 f Polyolefin Polyolefin of propylene-ethylene copolymer 85000 100 g Polyester Terephthalic acid-adipic acid-sebacic acid-ethylene glycol-butanediol copolymer polyester 10000 100 h Polyurethane Polyurethane of polyester polyol-diphenylmethane diisocyanate copolymer 40000 90 i Polyester Polyester of naphthalenedicarboxylic acid-PTMG-butanediol copolymer 140000 180 j Polyester elitel UE3320 1800 63 k Polyester elitel UE3690 14000 160

<Production example of resin pellets containing two or more types of thermoplastic resins and having a core-sheath structure> Manufacturing example 1 The crystalline polyester resin a (Tm: 160°C, Mw: 100000) and the crystalline polyester resin b (Tm: 160°C, Mw: 69000) are supplied to the biaxial extruder for the core, and the crystalline polyester resin b (Tm: 160°C, Mw: 69000) is supplied to a uniaxial extruder for sheath. The mass ratio W(A)/W(B)=0.43 of the crystalline polyester resin a to the crystalline polyester resin b from each extruder from each extruder at a temperature of 180°C, the core-sheath ratio (mass ratio ) Core/sheath=85/15 is supplied to the core-sheath mold. After the extruded strands are cooled and solidified in a water tank, they are cut with a pelletizer to obtain resin pellets with a core-sheath structure. In terms of the composition of the resin pellets, the core/sheath ratio (mass ratio) is 85/15, the sheath is crystalline polyester b100% by mass, the core is crystalline polyester a35% by mass, and the crystalline poly 65% by mass of ester b. That is, when the resin pellets are set to 100% by mass, the crystalline polyester resin b in the sheath is 15% by mass, the crystalline polyester resin a in the core is 30% by mass, and the crystalline polyester resin in the core is 30% by mass. b is 55% by mass.

Manufacturing example 3 The thermoplastic polyamide resin d (Tm: 130°C, Mw: 130000) and the thermoplastic polyamide resin e (Tm: 130°C, Mw: 40000) are supplied to the core biaxial extruder, and the thermoplastic polyamide resin e (Tm: 130°C, Mw: 40,000) was supplied to a uniaxial extruder for sheath. It was supplied to the core-sheath mold at a temperature of 180°C from each extruder at a mass ratio W(A)/W(B)=0.43 and a core-sheath ratio (mass ratio) core/sheath=85/15. After the extruded strands are cooled and solidified in a water tank, they are cut with a pelletizer to obtain pellets with a core-sheath structure.

Manufacturing example 2, 4~7, 9~16 It was manufactured by the same method as Manufacturing Examples 1 and 3. However, the types and blending ratios of raw materials are changed according to Table 2.

Manufacturing example 8 The crystalline polyester resin a (Tm: 160°C, Mw: 100000) and the crystalline polyester resin b (Tm: 160°C, Mw: 69000) are blended in advance to a/b=30/70 (mass ratio) and supplied To a twin-shaft extruder. It is melted and kneaded by an extruder at a temperature of 180°C. After the extruded strands are cooled and solidified in a water tank, they are cut with a pelletizer to obtain pellets with a single-layer structure. However, the types and blending ratios of raw materials are changed according to Table 2.

Production Example 17 Amorphous polyester resin j with a softening point of 63°C (trade name: Elitel UE3320 manufactured by Unitika Co., Ltd., density 1.26g/cm ³ , glass transition temperature 40°C) was supplied to the core for biaxial extrusion Machine, the copolymerized polyester resin k (trade name: Elitel UE3690 manufactured by Unitika Co., Ltd., density 1.25 g/cm ³ , glass transition temperature 90° C., softening point 160° C.) was supplied to a sheath uniaxial extruder. It was supplied to the core-sheath mold from each extruder at a temperature of 180°C at a core-sheath ratio (mass ratio) core/sheath=80/20. After the extruded strands are cooled and solidified in a water tank, they are cut with a pelletizer to obtain resin pellets with a core-sheath structure.

[Table 2]

Using the pellets of the production examples described in Table 2, the adhesion test, the exudation test, and the fluidity test were evaluated. The evaluation results are shown in Table 3 below.

[table 3]

According to Table 3, Examples 1 to 11 have good adhesion and exudation, low melt viscosity, and good fluidity during molding. On the other hand, the comparative example cannot ensure the same adhesion and exudation properties, and even if it can be ensured, its fluidity is not good, and these characteristics cannot be fully satisfied. [Industrial Utilization]

The thermoplastic resin composition of the present invention has low melt viscosity during molding and excellent adhesion and exudation properties. Therefore, it is widely used as power electronic parts in automobiles, electrochemical products, and machine parts used in the medical field. The sealing material is useful.

[Figure 1] A schematic diagram showing a graph measured with a differential scanning calorimeter.

Claims (6)

A resin pellet, characterized in that it contains a thermoplastic resin (A) and a thermoplastic resin (B), The weight average molecular weight Mw (A) of the thermoplastic resin (A) is 85,000 to 130,000, and the weight average molecular weight Mw (A) of the thermoplastic resin (A) is equal to the weight average molecular weight Mw (B) of the thermoplastic resin (B) The ratio Mw(A)/Mw(B) is more than 1 and below 4, It has a core-sheath structure in which the thermoplastic resin (B) is contained in the sheath part, the thermoplastic resin (A) is contained in the core part, and the ratio of the thermoplastic resin (A) is greater in the core part than in the sheath part. Such as the resin pellet of claim 1, characterized by: the ratio of the mass fraction W(A) of the thermoplastic resin (A) to the mass fraction W(B) of the thermoplastic resin (B) W(A)/W (B) is 0.05~1. The resin pellet of claim 1 or 2, wherein the melting point of the thermoplastic resin (A) and the melting point of the thermoplastic resin (B) are both 100°C or higher. The resin pellet of claim 1 or 2, wherein the difference between the melting point of the thermoplastic resin (A) and the melting point of the thermoplastic resin (B) is 30°C or less. Such as the resin pellet of claim 1 or 2, wherein the ratio (mass ratio) of the core/sheath is 50/50~95/5. Such as the resin pellets of claim 1 or 2, which are used as hot-melt sealing materials.

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