JP6186793B2 - Silanol condensation catalyst-containing polyolefin and silane-crosslinked polyolefin - Google Patents

Description

  The present invention relates to a novel silanol condensation catalyst and a silane-crosslinked polyolefin containing the silanol condensation catalyst.

  Polyolefin such as polyethylene, ethylene-vinyl acetate copolymer, ethylene-propylene copolymer, etc. are graft copolymerized with an organic silane compound in the presence of a radical generator, and the resulting graft copolymer is molded into a predetermined shape. Molded products in which moisture is allowed to act on a silanol catalyst, thereby cross-linking molecules are widely used.

  This cross-linking method called silane water cross-linking is performed in a molding machine such as an extruder by allowing a radical generator to act on a polyolefin as a graft initiator, thereby graft-copolymerizing an alkoxysilane compound to the polyolefin, and then molding it. A cross-linking reaction is caused by allowing moisture to act on a molded product formed by a machine. The crosslinking reaction is caused by hydrolysis and condensation reaction of alkoxysilane by the action of a silanol condensation catalyst that is mixed in the molded product in advance or penetrated from the molded product surface.

  As the silanol condensation catalyst, organotin compounds are mainly used, but due to safety concerns such as environmental hormone problems, alternative catalysts have been proposed. For example, Patent Document 1 discloses organic sulfonic acids and their hydrolysis precursors, organic phosphoric acids and their hydrolysis precursors, and halogen acids as acidic silanol condensation catalysts. Patent Document 2 discloses an organometallic compound as a silanol condensation catalyst. Patent Document 3 discloses a silanol crosslinking catalyst sulfonic acid compound.

Special table 2008-533280 gazette JP 2002-146150 A Special table 2004-526808 gazette

  However, conventional silanol condensation catalysts are not always satisfactory in terms of performance such as catalyst activity (curing speed) and environmental load.

  An object of the present invention is to provide a novel silanol condensation catalyst having excellent catalytic performance and low environmental load, and a silane-crosslinked polyolefin using the same.

The present inventors have found that a certain type of phosphoric acid compound can be an excellent silanol condensation catalyst capable of achieving the above-mentioned problems, and have completed the present invention.
That is, the gist of the present invention is as follows [1] to [ 7 ].
[1] The following formula (1):

(In the formula, n represents an integer of 2 or more.)
Containing Cie silanol condensation catalysts and polyolefins such contain in phosphoric acid compound or a salt thereof, 1000 phosphate compound or the content of a salt thereof represented by the following formula (1) with respect to the polyolefin A silanol condensation catalyst-containing polyolefin, characterized by having a mass ppm to 40,000 mass ppm .

[2] The silolenic condensation catalyst- containing polyoleophine according to [1], wherein a viscosity of the phosphoric acid compound at 25 ° C. is 100 cp or more and 200000 cp or less .
[3] the silane-modified polyolefin, silane-crosslinked polyolefin, wherein the formed by incorporating a sheet silanol condensation catalyst containing polyolefin according to [1] or [2].
[ 4 ] The silane crosslinking according to [ 3 ], wherein the content of the phosphoric acid compound represented by the formula (1) or a salt thereof is 50 mass ppm or more and 2000 mass ppm or less with respect to the silane-modified polyolefin. Polyolefin.
[ 5 ] The silane-crosslinked polyolefin according to [ 3 ] or [ 4 ], further comprising an antioxidant.
[ 6 ] The silane-crosslinked polyolefin according to any one of [ 3 ] to [ 5 ], which is a molded product.
[ 7 ] The silane-crosslinked polyolefin according to [ 6 ], wherein the molded product is an electric wire / cable coating material, a pipe, a hose, a tube, various containers, a sealing material, a film, or a sheet.

  ADVANTAGE OF THE INVENTION According to this invention, the silanol condensation catalyst which is excellent in catalyst performance, has little elution to warm water, and does not have an environmental load, an odor, coloring, etc. can be provided. The silane crosslinkable polyolefin containing the silanol condensation catalyst of the present invention can be particularly suitably used as a molded product of an electric wire / cable coating material, pipe, hose, tube, various containers, sealing material, film, sheet and the like.

  Hereinafter, the present invention will be described in more detail. The present invention is not limited to the embodiments described below, and can be implemented with various modifications within the scope of the gist.

(1) Silanol condensation catalyst The silanol condensation catalyst of the present invention comprises:
Following formula (1):

(In the formula, n represents an integer of 2 or more.)
It is characterized by containing the phosphoric acid compound represented by these, or its salt.

As described above, in the present invention, the phosphoric acid compound represented by the formula (1) used as a silanol condensation catalyst is composed of tetrahedral PO ₄ (phosphoric acid) structural units bonded by sharing an oxygen atom. . The phosphate compound may have a linear structure or a cyclic structure. Moreover, as a salt of a phosphoric acid compound, metal salts, such as sodium salt, calcium salt, aluminum salt, ammonium salt, etc. are mentioned. Among these, aluminum salts and calcium salts are preferable, and ammonium salts are more preferable.

  Moreover, as a salt, the organic alkali salt of the phosphoric acid compound represented by the said General formula (1) may be sufficient. Examples of the organic alkali that can be used include amines, triazines, and quaternary ammonium hydroxide.

  More specifically, examples of the amines include triethylamine, monoethanolamine, trimethanolamine, ethylenediamine, N, N, N ′, N′-tetramethyldiaminomethane, N, N′-dimethylethylenediamine, N, N′-diethylethylenediamine, N, N-dimethylethylenediamine, N, N-diethylethylenediamine, N, N, N ′, N′-tetramethylethylenediamine, 1,2-propanediamine, 1,3-propanediamine, tetramethylene Diamine, pentamethylenediamine, hexamethylenediamine, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, piperazine, trans-2,5-dimethylpiperazine, 1, 4-Bis (2-aminoethyl) pi Rajin, 1,4-bis (3-aminopropyl) piperazine, and the like.

  Examples of triazines include melamine, acetoguanamine, benzoguanamine, acrylic guanamine, 2,4-diamino-6-nonyl-1,3,5-triazine, 2,4-diamino-6-hydroxy-1,3,5. -Triazine, 2-amino-4,6-dihydroxy-1,3,5-triazine, 2,4-diamino-6-methoxy-1,3,5-triazine, 2,4-diamino-6-ethoxy- 1,3,5-triazine, 2,4-diamino-6-propoxy-1,3,5-triazine, 2,4-diamino-6-isopropoxy-1,3,5-triazine, 2,4-diamino -6-mercapto-1,3,5-triazine, 2-amino-4,6-dimercapto-1,3,5-triazine and the like can be mentioned.

  Examples of the quaternary ammonium hydroxide include tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide, trimethyl (hydroxyethyl) ammonium hydroxide, triethyl (hydroxyethyl) ammonium hydroxide, and the like.

  Furthermore, even if the silanol condensation catalyst in the present invention is a single compound selected from the phosphoric acid compounds represented by the formula (1), it is a mixture of compounds having different numbers of n (degree of polymerization) and different types of salts. There may be.

  In the formula (1), the number of n (polymerization degree) is not particularly limited as long as it is 2 or more, and may have any degree of polymerization as long as it is available. Here, in the compound represented by the formula (1), those having n of 2 are usually called “diphosphoric acid”, and polymers having n of more than 2 or a mixture thereof are usually called “polyphosphoric acid”. Generally, the commercially available polyphosphoric acid is a mixture of a compound of n = 1 (phosphoric acid) and a polymer of n = 2 or more, and the silanol condensation catalyst of the present invention does not impair the effects of the present invention. And n = 1 may be contained.

  The number of n (degree of polymerization), that is, the molecular weight of the phosphoric acid compound usually correlates with the viscosity. The viscosity of the phosphate compound represented by the formula (1) is usually 100 cp or more, preferably 500 cp or more, more preferably 1000 cp or more, further preferably 5000 cp or more, and usually 200000 cp or less, preferably 180000 cp or less, more Preferably it is 150,000 cp or less, More preferably, it is 100,000 cp or less. If the viscosity is too low, it tends to be eluted in warm water, and if the viscosity is too high, handling tends to deteriorate. The viscosity is a value measured at 25 ° C. using an E-type viscometer.

  There is no restriction | limiting in particular in content of the phosphoric acid compound represented by Formula (1) in the silanol condensation catalyst of this invention, or its salt, Content as a use condition mentioned later, and a use condition mentioned below as a silanol condensation catalyst It may be a content that can express the function.

  As described above, organotin compounds that have been used mainly as conventional silanol condensation catalysts have safety concerns due to environmental hormone problems. Moreover, the organic sulfonic acid proposed as a non-tin condensation catalyst and its hydrolysis precursor (for example, refer patent document 1) have a problem of coloring and odor. In contrast, the silanol condensation catalyst of the present invention has excellent catalytic performance, no environmental hormone problems, no coloring or odor problems, little elution into warm water, and easy handling. Is.

(2) Silanol condensation catalyst-containing polyolefin The silanol condensation catalyst-containing polyolefin of the present invention is characterized by containing the above silanol condensation catalyst and polyolefin. This silanol condensation catalyst-containing polyolefin is used as a master batch of a silanol condensation catalyst when preparing a silane-crosslinked polyolefin described later.

  A silanol condensation catalyst-containing polyolefin can be obtained by kneading and granulating a silanol condensation catalyst and a polyolefin. The silanol condensation catalyst-containing polyolefin is usually in the form of granules or pellets, but the preferred form is pellets.

Examples of polyolefins that can be used include ethylene homopolymers (polyethylene), α-olefins other than ethylene and ethylene, vinyl esters (such as vinyl acetate), and unsaturated carboxylic acid esters (such as ethyl acrylate). Examples thereof include copolymers, propylene homopolymers, copolymers of propylene as a main component and α-olefins (including ethylene) other than propylene. Among these, polyethylene and copolymers of ethylene and α-olefins other than ethylene are particularly preferable.
These may be used alone or in combination of two or more in any combination.

  As the silanol condensation catalyst, a compound selected from the group consisting of the phosphoric acid compound represented by the above formula (1) or a salt thereof may be used alone, or two or more kinds may be used in any combination. Moreover, you may use together another silanol condensation catalyst as needed.

  The lower limit of the content of the silanol condensation catalyst is usually 1000 ppm by mass or more, preferably 2000 ppm by mass or more, more preferably 3000 ppm by mass or more, and the upper limit is usually 40000 ppm by mass or less, preferably 30000 mass with respect to the polyolefin. ppm or less, more preferably 20000 mass ppm or less. If the content is too small, the crosslinking reaction does not proceed sufficiently, and if it is too large, the appearance tends to deteriorate. In addition, "content of a silanol condensation catalyst" here is content of the phosphoric acid compound or its salt represented by Formula (1).

  If necessary, miscible thermoplastic resins, antioxidants (stabilizers), lubricants, fillers, colorants, foaming agents, and other auxiliary materials can be added to the silanol condensation catalyst-containing polyolefin. These additives may be those commonly used and known per se, and those similar to those described later are used.

(3) Silane-crosslinked polyolefin The silane-crosslinked polyolefin of the present invention is characterized in that the silane-modified polyolefin contains the silanol condensation catalyst or the silanol condensation catalyst-containing polyolefin. Here, the silane-crosslinked polyolefin includes a molded product. In addition, the silane-modified polyolefin includes those prepared by performing a silanol condensation catalyst simultaneously with the silane modification (grafting reaction) of the polyolefin. That is, the silane-crosslinked polyolefin of the present invention includes all of the silane-crosslinked polyolefin containing the silanol condensation catalyst of the present invention regardless of its production method or molding state. Furthermore, what contains additives, such as antioxidant, is also included in the silane crosslinked polyolefin of this invention. This will be described in more detail below.

(A) Silane-modified polyolefin Examples of the polyolefin in the silane-modified polyolefin used in the present invention include ethylene homopolymer (polyethylene), α-olefin other than ethylene and ethylene as main components, vinyl esters (for example, vinyl acetate, etc.) Examples thereof include a copolymer with a saturated carboxylic acid ester (for example, ethyl acrylate), a propylene homopolymer, a copolymer of propylene as a main component and an α-olefin (including ethylene) other than propylene. Among these, polyethylene and copolymers of ethylene and α-olefins other than ethylene are particularly preferable. These may be used alone or in combination of two or more in any combination.

  The silane-modified polyolefin is obtained by, for example, copolymerizing the above polyolefin with an olefinically unsaturated silane compound having a hydrolyzable organic group in a molding processing machine such as an extruder in the presence of a radical generator. can get. In this reaction, the unsaturated silane compound is grafted to the polyolefin so that it becomes a cross-linking point between the polyolefins as the base. The obtained silane-modified polyolefin is sometimes referred to as “polyolefin grafted with a silane compound”.

Here, the olefinically unsaturated silane compound having a hydrolyzable organic group is represented by the following formula (2):
RSiR ′ _n Y _3-n (2)
(In the formula, R represents a monovalent olefinically unsaturated hydrocarbon group, Y represents a hydrolyzable organic group, and R ′ is the same as a monovalent hydrocarbon group other than aliphatic unsaturated hydrocarbon or Y. And n represents 0, 1 or 2.)
The silane compound represented by these.

  In the formula (2), R is preferably a vinyl group, allyl group, isopropenyl group, butenyl group, R ′ is preferably a methyl group, ethyl group, propyl group, decyl group, phenyl group or the like, Y is a methoxy group, An ethoxy group, formyloxy group, acetoxy group, propionoxy group, alkyl or arylamino group is preferred.

Moreover, as a preferable silane compound, for example, the following formula (3)
CH ₂ = CHSi (OA) ₃ (3)
(In the formula, A represents a monovalent hydrocarbon group having 1 to 8 carbon atoms.)
The compound represented by these is mentioned.

More specifically, for example, represented by vinyltrimethoxysilane, _{vinyltriethoxysilane, CH 2 = C (CH 3} ) COOC 3 H 6 Si (OA) 3 ( where, A is as defined above.) Examples thereof include γ-methacryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropyltriethoxysilane, and the like. Among these, vinyltrimethoxysilane, vinyltriethoxysilane, and γ-methacryloyloxypropyltriethoxysilane are preferable.
These may be used alone or in combination of two or more in any combination.

  The addition amount of these compounds is usually 0.01% by mass or more, preferably 0.1% by mass or more, more preferably 0.7% by mass or more, based on the total mass of the silane-modified polyolefin. Is usually 15% by mass or less, preferably 10% by mass or less, more preferably 7% by mass or less, and further preferably 4% by mass or less. If the addition amount is too small, sufficient grafting tends to be difficult, and if it is too much, molding tends to be poor and it is not economical. This added amount has the same meaning as the unit derived from the silane compound in the silane-modified polyolefin.

  Examples of the radical generator used include various organic peroxides and peresters having a strong polymerization initiating action, such as dicumyl peroxide, α, α'-bis (t-butylperoxydiisopropyl) benzene, di-t. -Butyl peroxide, t-butylcumyl peroxide, di-benzoyl peroxide, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane, t-butylperoxypivalate, di-t- Examples include butyl peroxide and t-butyl peroxy-2-ethylhexanoate. Of these, dicumyl peroxide and benzoyl peroxide are preferred. These radical generators may be used alone or in combination of two or more in any combination.

  The amount of the radical generator used is usually 0.01% by mass or more, preferably 0.02% by mass or more, more preferably 0.03% by mass or more, based on the total mass of the silane-modified polyolefin. The upper limit is usually 0.5% by mass or less, preferably 0.4% by mass or less, and more preferably 0.2% by mass or less. If the amount used is too small, a sufficient grafting reaction tends to be difficult, and if it is too large, the extrusion processability is lowered and the molding surface tends to be deteriorated.

  The silane-modified polyolefin is a normal random copolymer of the silane compound with, for example, ethylene, and is a copolymer obtained by radical copolymerization under normal high pressure polymerization conditions in low density polyethylene. There may be. In the case of this radical copolymerization, vinyl acetate, acrylic acid, methacrylic acid and esters thereof may be further copolymerized. The content of units derived from the silane compound in these copolymers is the same as described above.

  Of the silane-modified polyolefins, polyolefins grafted with silane compounds are preferred. In addition, the silane-modified polyolefin used in the present invention may be a blend of two or more silane-modified polyolefins or a blend of silane-modified polyolefin and polyolefin if the content of units derived from the silane compound is appropriate. Used.

(B) Content of silanol condensation catalyst The lower limit of the silanol condensation catalyst content in the silane-crosslinked polyolefin is usually 50 ppm by mass or more, preferably 100 ppm by mass or more, more preferably 200 ppm by mass or more. Yes, the upper limit is usually 2000 ppm by mass or less, preferably 1500 ppm by mass or less, more preferably 1000 ppm by mass or less. If the content is too small, the crosslinking reaction does not proceed sufficiently, and if it is too large, the appearance tends to deteriorate. In addition, "content of a silanol condensation catalyst" here is content of the phosphoric acid compound or its salt represented by Formula (1).

  The silanol condensation catalyst may be contained by dry blending or may be contained as a master batch, and the addition method is not particularly limited. Moreover, you may use together silanol condensation catalyst other than the phosphoric acid compound represented by the said Formula (1) or its salt as needed.

(C) Additives The silane-crosslinked polyolefin of the present invention may contain miscible thermoplastic resins, antioxidants, lubricants, fillers, colorants, foaming agents, and other auxiliary materials as necessary. Can do. These additives may be those commonly used and known per se.

Among these, it is preferable to contain an antioxidant particularly for improving the heat-resistant deterioration characteristics. Examples of the antioxidant that can be used include 2,2-thio-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], pentaerythrityl-tetrakis [3- (3 , 5-di-t-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, 2,4-bis- (n-octylthio) 6- (4-hydroxy-3,5-di -t- butylanilino) -1,3,5-triazine, bis [2-methyl-4-{3-n-alkyl _{(C 12} or _{C 14)} thiopropionyl Oxy} -5-tert-butylphenyl] sulfide, 4,4′-thiobis (3-methyl-6-tert-butylphenol), dilauryl thiodipropionate, dimi Still thiodipropionate, distearyl thiodipropionate, ditridecyl thiodipropionate, tetrakis (methylene-dodecyl thiodipropionate) methane, and the like.
These antioxidants may be used alone or in combination of two or more in any combination.

  As for the content of the antioxidant, the lower limit is usually 10 mass ppm or more, preferably 50 mass ppm or more, more preferably 100 mass ppm or more, and the upper limit is usually 20000 mass ppm or less, preferably 15000, relative to the silane-crosslinked polyolefin. The mass ppm or less, more preferably 13000 mass ppm or less. If the amount added is too small, the improvement in heat-resistant deterioration characteristics is not sufficient, and if it is too large, the appearance may deteriorate due to precipitation on the surface of the molded product.

  Additives such as antioxidants may be in the form of a dry blend with respect to the polyolefin, or a master batch in which these antioxidants are mixed in the polyolefin in a high concentration may be added. Further, it can be dissolved in a silane compound and mixed with polyolefin in a molding machine such as an extruder together with the addition of the silane compound.

(D) Preparation of Silane Crosslinked Polyolefin The silane crosslinked polyolefin can be prepared by adding a silanol condensation catalyst and, if necessary, an additive to the silane modified polyolefin.

  Specific examples of the method for incorporating the silanol condensation catalyst into the silane-modified polyolefin include a method in which the silanol condensation catalyst is dissolved or dispersed in an organic solvent or the like, and this is impregnated or contacted with the silane-modified polyolefin. The organic solvent in this case is not particularly limited, and examples thereof include toluene, xylene, acetone and the like.

  Other methods for incorporating the silanol condensation catalyst into the silane-modified polyolefin include a method of melt-kneading the silane-modified polyolefin and the silanol condensation catalyst, or a silanol condensation catalyst previously contained in a resin different from the silane-modified polyolefin. And a method of melt-kneading the resin and silane-modified polyolefin. Although the apparatus and conditions at the time of melt-kneading are not specifically limited here, the apparatus and conditions which can be used when performing said graft modification by melt-kneading are applicable similarly.

  In the present invention, the preparation of a silane-crosslinked polyolefin is introduced into a polyolefin in a molding machine such as an extruder together with a silane compound and a radical generator, a silanol condensation catalyst, and an additive such as an antioxidant as required. At the same time as the silane modification (grafting reaction) of the polyolefin, a silane crosslinkable polyolefin can be prepared and subsequently formed into a molded product according to the application.

(E) Molded product The silane-crosslinked polyolefin is usually subjected to practical use as a molded product after being molded according to the use and then crosslinked with moisture. As described above, the molding may be performed using an appropriate molding machine such as an extruder.

  The crosslinking method is not particularly limited, but for example, a method of immersing the molded product in a constant temperature water bath, a method of leaving (immersing) in a steam, or a method of leaving under humidification is preferable. The lower limit of the temperature is usually 10 ° C or higher, preferably 40 ° C or higher, more preferably 60 ° C or higher, and the upper limit is usually 130 ° C or lower, preferably 120 ° C or lower, more preferably 110 ° C or lower. The lower limit of the humidity is usually 30% RH or more, preferably 40% RH or more, more preferably 50% RH or more, and the lower limit is usually 100% RH or less.

The gel fraction of the silane-crosslinked polyolefin in the present invention is usually 30% by mass or more, preferably 40% by mass or more, more preferably 50% by mass or more. When the gel fraction of the silane-crosslinked polyolefin is within the above range, good heat resistance can be obtained. The upper limit of the gel fraction of the silane-crosslinked polyolefin is not particularly limited, and may be complete crosslinking (gel fraction 100% by mass). In addition, the value of the said gel fraction is a thing after the bridge | crosslinking by a water | moisture content. The silane-crosslinked polyolefin of the present invention includes those having a gel fraction of less than 30%.
Here, the gel fraction represents the insoluble matter when extracted with boiling xylene using a Soxhlet extractor for 10 hours as a percentage of the mass before extraction.

The silane-crosslinked polyolefin of the present invention can be particularly suitably used as a molded product of an electric wire / cable coating material, a pipe, a hose, a tube, various containers, a sealing material, a film, a sheet, and the like.
Molded articles for these uses can be produced by methods known per se as described above, but the following methods (i) and (ii) are preferred.
(I) A master batch containing a silanol condensation catalyst at a high concentration is prepared, and this is fed together with a silane-modified polyolefin to an extruder and extruded (two-shot method).
(Ii) An additive containing a silanol condensation catalyst and a radical generator is supplied to the polyolefin in the extruder, whereby the graft reaction of the silane compound to the polyolefin and the extrusion molding are simultaneously performed in one extruder (one-shot method). .

In addition, as a method of making the silanol condensation catalyst act on polyolefin, it is possible to infiltrate from the surface of the molded polyolefin other than the method of kneading the silanol catalyst into the polyolefin as described above.
A molded product suitable for a desired use can be obtained by crosslinking with moisture after molding as described above.

  Hereinafter, the present invention will be described more specifically with reference to experimental examples (Examples, Comparative Examples, Reference Examples). In addition, the values of various production conditions and evaluation results in the following examples have meanings as preferable values of the upper limit or the lower limit in the embodiment of the present invention, and the preferable range is the above-described upper limit or lower limit value. It may be a range defined by a combination of values of the following examples or values of the examples.

[Examples 1 to 5, Comparative Example 1, Reference Example 1]
Polyolefin resin (LD400, manufactured by Nippon Polyethylene Co., Ltd.), silanol condensation catalyst (phosphoric acid, diphosphoric acid, polyphosphoric acid; manufactured by Kishida Chemical Co., Ltd., phosphate-1 (a salt of a phosphoric acid compound contained in formula (1) as a main component) Adeka Stub FP-2100J); manufactured by Adeka, di-n-octyltin dilaurate), antioxidant-1 (RA1010, manufactured by BASF), antioxidant-2 (MD1024, manufactured by BASF) , Antioxidant-3 (Sumilyzer WXRC, manufactured by Sumitomo Chemical Co., Ltd.), Lubricant-1 (Viton Freeflow SCPL100, manufactured by DuPont) were inserted into a pressure kneader having an internal capacity of 1.0 L in the ratio shown in Table 1. The kneading was terminated when the temperature of the pressure kneader was 120 ° C. and the resin temperature reached 150 ° C. due to self-heating due to shear heat generation. The obtained mixture was formed into a sheet with a roll and then pelletized with a letterer to prepare a silanol condensation catalyst master batch.

  A mixture of 5 parts by mass of the obtained silanol condensation catalyst masterbatch with 100 parts by mass of silane-modified polyolefin (Linkron XCF800N, manufactured by Mitsubishi Chemical Corporation) was extruded at a temperature of 210 ° C. with a 20 mmφ extruder and extruded with a thickness of 1 mm. Created a sheet. The obtained extruded sheet was immersed in 80 ° C. warm water or 95 ° C. steam for a predetermined time to perform a crosslinking treatment to obtain a silane crosslinked polyolefin. The gel fraction was measured using the extruded sheet of the obtained silane-crosslinked polyolefin. These results are shown in Table 2.

  In addition, the viscosity in Table 1 is a value measured at 25 ° C. using an E-type viscometer. The gel fractions in Table 2 are obtained by performing Soxhlet extraction on a silane-crosslinked polyolefin sheet (thickness 1 mm) in boiling xylene at 144 ° C. for 10 hours, and then measuring the mass after drying the undissolved resin. It is a value calculated as a ratio (%) to the sample mass before extraction.

  As is clear from the values of the gel fractions in Table 2, all of Examples 1 to 5 show a better gel fraction than Comparative Example 1, and it is recognized that they have a low elution property with respect to water. This is an excellent silanol condensation catalyst that can be substituted for known acidic silanol condensation catalysts and organotin compounds and has low elution and no environmental hormone problems, and has great utility.

Claims (7)

A silanol condensation catalyst containing a phosphoric acid compound represented by the following formula (1) or a salt thereof and a polyolefin are contained , and the content of the phosphoric acid compound represented by the following formula (1) or a salt thereof is in the polyolefin. silanol condensation catalyst containing polyolefin, characterized in 40000 ppm by mass or less der Rukoto more than 1000 ppm by mass for.

(In the formula, n represents an integer of 2 or more.) 2. The silanol condensation catalyst- containing polyolefin according to claim 1, wherein a viscosity of the phosphoric acid compound at 25 ° C. is 100 cp or more and 200000 cp or less. The silane-modified polyolefin, silane and wherein the formed by incorporating a sheet silanol condensation catalyst containing polyolefin according to claim 1 or 2 cross-linked polyolefin. The silane-crosslinked polyolefin according to claim 3 , wherein the content of the phosphoric acid compound represented by the formula (1) or a salt thereof is 50 mass ppm or more and 2000 mass ppm or less with respect to the silane-modified polyolefin. Furthermore, antioxidant is contained, The silane crosslinked polyolefin of Claim 3 or 4 characterized by the above-mentioned. The silane-crosslinked polyolefin according to any one of claims 3 to 5 , which is a molded product. The silane-crosslinked polyolefin according to claim 6 , wherein the molded product is an electric wire / cable coating material, a pipe, a hose, a tube, various containers, a sealing material, a film or a sheet.