JPH03269026A - Composition of non-staining open-cell type propylene based resin foam - Google Patents

Abstract

PURPOSE:To obtain the title composition containing a propylene based resin, an ethylene based resin-organopolysiloxane-diene-containing hydrocarbon kneaded compound and a foaming agent, having excellent heat resistance, mechanical strength, water permeable properties, etc., and capable of providing a foam suitable as a filter. CONSTITUTION:The aimed composition containing (A) 100 pts.wt. propylene based resin (preferably having 0.2-10g/min MFR at 230 deg.C), (B) 0.1-100 pts, preferably 5-30 pts.wt. ethylene based resin-organopolysiloxane-diene-containing hydrocarbon kneaded compound having >=10% gel content and (C) 1-30 pts.wt. foaming agent (e.g. azobisisobutylonitrile). Furthermore, the component B is preferably obtained by adding 10-900 pts.wt. organopolysiloxane expressed by formula I (R<1> is aliphatic unsaturated group; R<2> is monovalent hydrocarbon containing no aliphatic unsaturated group; 0<=a<1; 0.5<b<3; 1<a+b<3) and 0-1 pts.wt. organic peroxide expressed by formula II (c is 1-30) to 100 pts.wt. ethylene based resin and heating and kneading the blend.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a composition for use in a flexible open-cell propylene resin foam with low staining properties. More specifically, the present invention relates to a resin composition from which an open-cell propylene resin foam having excellent heat resistance, mechanical properties, chemical resistance, etc. It is used in heat insulating materials, automobile interior materials, various mat materials, etc., and is particularly suitable as various filter materials.

(Prior art) Since propylene resin is a highly crystalline resin with stereoregular coordination, its melting point is about 30 to 30% compared to ethylene resin.
Since it has excellent heat resistance (50°C higher) and excellent mechanical strength, foams made from it have been proposed.

Propylene resins have a higher melting point and lower melt viscosity than ethylene resins, and the viscosity changes rapidly near the melting point, so the temperature range suitable for extrusion foaming is extremely narrow. It is difficult to uniformly knead blowing agents, and even if it were possible to mix them, only blowing agents with a high decomposition temperature can be used, and the range of blowing agent selection is narrow.

In addition, in order to obtain an appropriate melt viscosity for foaming, crosslinking with an organic peroxide can be considered as a diversion from polyethylene foaming technology, but due to the molecular structure of polypropylene, it contains tertiary carbon "λ," The decomposition reaction takes precedence over the reaction, and no effective effect can be obtained unless a crosslinking aid is used.

To solve these problems, it is possible to lower the melting point of the polymer by copolymerizing propylene with other monomers, resulting in a relatively high melt viscosity and little change in melt viscosity over a wide temperature range. Proposed (Special Publication No. 60-26418, Special Publication No. 6l-I460, etc.)
There is also a proposal for blending a styrene-isoprene block copolymer in order to prevent the melt viscosity from decreasing (Japanese Patent Publication No. 6O-39697). Furthermore, by modifying a propylene resin with an alkoxy group-containing vinyl silane and water-crosslinking it, A method of increasing the melt viscosity comparatively has also been proposed (Japanese Patent Publication No. 61-18933). Foams made from propylene resin have come to be manufactured industrially using these methods, but their cell structures are all closed cells;
Open-celled ones have never been proposed.

(Problems to be Solved by the Invention) The present invention solves the problem that the conventional propylene resin foam has a closed cell structure and has poor air permeability, softness, flexibility, etc., and in particular has no air permeability at all. Since it cannot be used as a plastic material, our object is to propose an open-cell propylene resin foam to solve these problems.

Another issue with this open-cell foam is that internal additives migrate to the surface, solving problems such as surface stickiness, dust adsorption, adhesion to the human body or clothes, and deterioration of the maiko. do.

(Means for solving the problem) As mentioned above, propylene resin has a high melting point, and the viscosity decreases rapidly above the melting temperature of the crystals. Providing an appropriate melt viscosity is an important technical point in making a foam, and creating an open-cell foam requires special means.

The present inventors have applied for numerous patents regarding the technology for obtaining open-cell foams using ethylene resin as a material (Japanese Patent Publication No. 60-49657, Japanese Patent Publication No. 60-12463).
2, 62-89738, 62-89739, 62
-89741, 62-89742, 63-1130
34, 63-113035, 63-126733,
Patent application No. 63-260620. Patent Application No. 63-260621, Patent Application No. 1-154636, No. 1-154637, No. 1-2
64419, 1-276149, etc.).

The present invention has been completed by developing these techniques and applying them to propylene-based resins.

That is, the present invention comprises: (1) a) 100 parts by weight of a propylene resin, b) 0.1 to 100 parts by weight of an ethylene resin-organopolysiloxane-diene-containing hydrocarbon kneaded product having a gel content of 10% or more;
and C) a non-staining open-cell propylene resin foam composition containing 1 to 30 parts by weight of a blowing agent.

(2) Above b) Ethylene resin with gel content of 10% or more -
The organopolysiloxane-diene-containing hydrocarbon kneaded product contains (10 to 9 parts of organopolysiloxane represented by formula A1) per 100 parts by weight of ethylene resin.
00 parts by weight (wherein R1 is an aliphatic unsaturated group, R1 is an unsubstituted or substituted monovalent hydrocarbon group that does not contain an aliphatic unsaturated group, O≦a<1
．． 0.5 < b < 3.1 < a + b < 3), (B) 0.01 to 30 parts of a hydrocarbon compound represented by the formula CHzICH (Ctlz) CCH TomiCHi
(B) (wherein C is an integer of 1 to 30) and 0 to 1 part by weight of an organic peroxide, and is obtained by heating and kneading. This is a composition for stain-prone open-cell propylene resin foam.

In the present invention, the propylene resin is a polymer whose main component is propylene, including propylene homopolymer, propylene and other α-olefins (ethylene, butene-1,
4-methyl-pentene-1, hexene-1, octene-1
1, etc.), and is a block or random copolymer with MF
R (melt flow rate) is 0.1 to 20 (g/w
(in 230°C) and is preferably 0.2 to 10. 0.
If it is less than 1, it will be difficult to mix with the foaming agent and the extrusion processability will be poor, and if it is more than 20, the melt viscosity will decrease and foaming will become difficult. Specific examples include polypropylene,
propylene-ethylene block or random copolymer,
Examples include propylene-butene-1 block or random copolymer propylene-ethylene-butene-1, random or block copolymer.

In the present invention, an ethylene resin-organopolysiloxane-diene-containing hydrocarbon kneaded material having a gel content of 10% or more means 10 to 9 parts of organopolysiloxane represented by formula (A) based on 100 parts by weight of ethylene polymer.
00 parts by weight R'a R"b SiOj, L, L(A) (in the formula, R'
is an aliphatic unsaturated group, R2 is an unsubstituted or substituted monovalent hydrocarbon group containing no aliphatic unsaturated group, 0≦a<1.0.5<
b < 3.1 < a + b < 3), 0.01 to 30 parts of a hydrocarbon compound represented by formula (B) CHz"CH(CHx)CCH=CHz
(B) (wherein C is an integer of 1 to 30) is added and kneaded under heat, and the kneaded product has a gel content of 10% or more.

The above ethylene polymers are ethylene homopolymers,
or ethylene and α-olefins, vinyl esters, unsaturated carboxylic acids such as propylene, butene-1, foamed-methyl-pentene-1, hexene-1, octene-1, nonene-1, decene-1, dodecene-1, etc. , unsaturated carboxylic acid esters, etc., such as high-pressure low-density polyethylene, medium-low pressure high-density, medium-density polyethylene, vapor-phase polyethylene, ethylene-propylene copolymer. , ethylene-vinyl acetate copolymer, ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate copolymer, and the like.

In the organopolysiloxane represented by the formula (A), examples of the R1 group include a vinyl group, allyl group, acrylic group, and methacryl group, and examples of the R2 group include:
Alkyl groups such as methyl, ethyl, and propyl groups, aryl groups such as phenyl and tolyl groups, cycloalkyl groups such as cyclohexyl and cyclobutyl groups, and hydrogen bonded to carbon atoms of these hydrocarbon groups are partially Examples include groups substituted with halogen atoms, cyano groups, mercapto groups, etc., and these may be the same or different combinations.

Further, X needs to be greater than 0 and less than 1, preferably from 0.0004 to 0.06. X is O
If it is more than 1, the reaction with the ethylene resin will not occur, and if it is more than 1, the foam produced from the composition of the present invention will become too hard, which is not desirable.

y needs to be greater than 0.5 and less than 3, preferably 1-2. If y is less than 0.5, it will be difficult for the composition of the present invention to cross-wire, resulting in poor processability, and if y is greater than 3, the foam produced from the composition of the present invention will become too hard, which is undesirable.

The molecular structure of the organopolysiloxane of the present invention may be linear, branched, cyclic, network, three-dimensional network, etc., as long as it is within the range of formula (A). Preferably.

The degree of polymerization of this organopolysiloxane is not particularly limited, but the degree of polymerization must be such that it does not interfere with crosstalk with the ethylene resin, and a degree of polymerization of 250 or more is desirable.

Examples of the organopolysiloxane used in the present invention include so-called silicone gum stock, which is commercially available as a tear strength improver for silicone rubber. In addition, the linear organopolysiloxane used in the present invention has the general formula (wherein R represents an unsubstituted or substituted monovalent hydrocarbon group, n
represents a number of 10 or more). There is something commonly called silico oil.

R in the formula is a group selected from an alkyl group, an aryl group, and hydrogen, and includes a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, and a t-
Typical examples are butyl group, phenyl group, and hydrogen, but
All the groups may be the same group, some of the R's may be different groups, and some of the R's may be a vinyl group or a hydroxyl group.

n is 10-10.000, preferably 100-1.000.

If n is smaller than 10, crosstalk with polyethylene will be difficult, and if n is larger than 10,000, it will be difficult to form a film, which is not desirable.

The viscosity at 23° C. of the organopolysiloxane polymer of formula (A) used in the present invention is [OCS] or higher, preferably 1000 to 1,000,000 O8. If the viscosity is lower than 10 C8, Heating crosstalk is difficult, and the organopolysiloxane polymer may ooze out from the surface of the molded product.

Examples of the hydrocarbon compound represented by formula (6) include 1,4-pentadiene, 1,5-hexadiene, 1
．． 6-hebutadiene, 1,7-octadiene, 1.8-
Nonadiene, 1,9-decadiene, 1゜10-undecadiene, 1.11-dodecadiene, 1.12-tridecadiene, 1.13-tetradecadiene, 1.14-pentadecadiene, 1.15-hexadecadiene, 1 .16
-hebutadecadiene, 1.17-octadecadiene, 1
, 18-nonadecadiene and the like.

The organic peroxide used in the present invention has a decomposition temperature with a half-life of 10
Preferably, the temperature is 100 to 220° C. per minute, that is, the half-life temperature is 100 to 220° C. for 10 minutes, and examples of such materials include the following.

However, the value in parentheses is the decomposition temperature ("C).

Succinic acid peroxide (110), benzoyl peroxide (110), t-butylperoxy-2-ethylhexanoate (113), p-chlorobenzoyl peroxide (115), t-butylperoxyisobutyrate (115), t- Butylperoxyisopropyl carbonate (135), t-butylperoxylaurate (140), 2,5-dimethyl-2,5-di(benzoylperoxy)hexane (140), t-butylperoxyacetate (140), di- t-Butyl diperoxy phthalate (140), t-butyl peroxymaleic acid (140), cyclohexanone peroxide (1
45), t-butyl peroxybenzoate (145)
, dicumyl peroxide (150), 2,5-dimethyl-2,5-di(t-butylperoxy)hexane (15
5), t-butylcumyl peroxide (155), t
-butyl hydroperoxide (158), di-t-butyl peroxide (160), 2,5-dimethyl-25
-di(t-butylperoxy)hexyne-3 (170)
, di-isopropylbenzene hydroperoxide (17
0), p-menthane hydroperoxide (180), 2
．． 5-dimethylhexane-25-dihydroperoxide (213).

In the present invention, the amount of organopolysiloxane is desirably 10 to 900 parts by weight per 100 parts by weight of the ethylene polymer; if it is less than 10 parts by weight, an open cell foam cannot be obtained and flexibility will be lost, which is not desirable. When the amount is more than 900 parts by weight, the mechanical strength of the foam becomes weak and the rebound resilience of the foam disappears, which is not desirable.

In the present invention, when using an organic peroxide, it is preferably 1 part by weight or less per 100 parts by weight of the ethylene polymer. By using a small amount of the organic peroxide, the gel content can be easily adjusted in a short time. However, if the amount is more than 1 part by weight, the gel content becomes too high, making it difficult to add the foaming agent to the kneaded product, and the melt viscosity of the foamed cell membrane becomes too high, making it difficult to foam. In some cases.

The amount of the terminal diene hydrocarbon compound represented by the formula (B) used in the present invention is preferably 0.01 to 30 parts by weight per 100 parts by weight of the ethylene polymer.
If the amount is less than 1 part by weight, a large amount of aggregated silicone crosslinked material may be generated, which is not desirable.

In addition, if the amount is more than 30 parts by weight, the gel content tends to increase, making it difficult to obtain a flexible foam, and foaming is difficult to occur.
Gel content: 10% based on 100 parts by weight of propylene resin
The amount of the above ethylene resin-organopolysiloxane-diene-containing hydrocarbon kneaded product is 0.1 to 100 parts by weight, preferably 5 to 30 parts by weight. If O is less than 1 part by weight, the open cell ratio of the foam will decrease, which is undesirable, and there will be no effect of mixing the blowing agent at a low temperature or an effect of increasing melt viscosity, and a foam will not be obtained. If the amount is more than 100%, a foam can be obtained, but the heat resistance, mechanical strength, and chemical resistance, which are characteristics of propylene resin foam, are impaired, which is not desirable.

In the present invention, when the amount of the ethylene resin-organopolysiloxane-diene-containing hydrocarbon kneaded product with a gel content of 10% or more is used in a small amount of 5% or less relative to the propylene resin, the melt viscosity of the resin decreases. Therefore, it is desirable to carry out crosslinking with an organic peroxide, or to modify the propylene resin in advance with an alkoxy group-containing vinylsilane, to mix a silanol condensation catalyst, and to carry out water crosslinking in the presence of moisture.

Of course, even if the content is 5% or more, the above-mentioned crosslinking effect is obtained.

When crosslinking with an organic peroxide, the decomposition of propylene resin is promoted, so hydroquinone, p-benzoquinone,
-Dinitobenzene, 0-nitrophenol, nitrosobenzene, t-butylcatechol, p-phenyl diamine, sulfur, etc. must be blended to prevent decomposition and allow only crosslinking reaction to occur.

Further, crosslinking may be performed by electron beam irradiation. In the crosslinking reaction, triallyl cyanurate, triallyl isocyanurate, ethylene glycol methacrylate, trimethylolpropane trimethacrylate, vinylbenzene, diallyl phthalate, vinyltoluene, ethylvinylbenzene, It is desirable to use a crosslinking aid such as quinone dioxime, benzoquinone dioxime, p-nitrophenol, N,Nm-phinidine bismaleimide, or the like.

The foaming agent used in the present invention has a foaming temperature of 90°C.
to 220°C, and preferably the decomposition temperature is higher than the crystalline melting point of the propylene resin used, and this also includes those in which the decomposition temperature is adjusted within this range by using an accelerator or auxiliary agent. Examples include:

Azobisisobutyronitrile, diazocarbonamide,
p-Toluenesulfonylhydrazide, 4,4'-oxybis(benzenesulfonylhydrazide), n-hebutane, n-octane, n-nonane, n-decane.

The amount of blowing agent required is 1 to 30 parts by weight. If it is less than 1 part by weight, there is almost no foaming effect, and if it is more than 30 parts,
This only increases the amount of foaming agent decomposition products that wastefully escape into the atmosphere during foaming, resulting in poor efficiency.

In the present invention, the composition may contain oxidation stabilizers, ultraviolet stabilizers, inorganic fillers, pigments, flame retardants, rubbers, etc., if necessary.

The temperature at which the composition of the present invention is heated is at least the temperature necessary for foaming and crosslinking, and specifically 1
It is between 50 and 300°C.

The gel content was calculated from the ratio of the remaining gel amount to the weight of the original sample after immersing the sample in toluene at 95° C. for 24 hours and vacuum drying the sample for 24 hours.

JIS hardness was measured using JIS 5K6301 type C.

[Example〕 Here, an example of the present invention will be shown.

30 g of ethylene-vinyl acetate copolymer (manufactured by Nippon Unicar) with a vinyl acetate content of 20 wt%
, 30 g of silicone gum stock (manufactured by Nippon Unicar) with a viscosity of 300.0 OOC5 at 23°C and a methyl vinyl silicone content of 1.0%, and 0.0 g of 1.9-decadiene.
6g, dicumyl peroxide 0.01g, and Irganox 1010 (antioxidant manufactured by Ciba Geigy) 0.0
1 g was mixed in a Brabender Plastograph at 100° C. for 5 minutes and then kneaded at 160”C for 15 minutes. The gel content of the resulting kneaded product was 58%.

Propylene with a melt index of 10 and a melting point of 145°C
For 100 g of ethylene copolymer, 10 g of this kneaded product,
Azocica-bonamide foaming agent "Cellmic C-2J"
(Foaming temperature 204℃: manufactured by Sankyo Kasei) 10g, 150
The mixture was kneaded in a roll mill at ℃ for 20 minutes and made into pellets. This pellet was compressed to 1 m at 170°C.
It was made into a sheet with a thickness of m. Pressure and time are each 100
kg/cm'' for 5 minutes. When this sheet was placed on a polyester sheet and placed in an oven at 220°C, it foamed in 8 minutes. When the foam was taken out and left to cool to room temperature. , thickness 2mm, average bubble diameter 0.
3mm, JIS hardness 40, maximum water absorption rate 0.23g/g
A bleed-free, open-cell foam was obtained.

1 piece of high-pressure polyethylene NUC-8008C: manufactured by L Nikaa) 10 kg, dimethylpolysiloxane FZ-31
10 kg of 12 (manufactured by Nippon Unicar) and 0.2 kg of l,13-tetradecadiene were added to DS20-40M manufactured by Moriyama Seisakusho.
The mixture was kneaded using a WA-H type kneader TI at 80° C. for 70 minutes.

The rotation speed of the blade was 45 rpm. The gel content of the obtained kneaded product was 65%.

To 100 g of polypropylene with a melt index of 10 and a melting point of 165°C, 10 g of this kneaded product was mixed with Azocica-bonamide foaming agent "Celmic C-2" (foaming temperature 20
4℃: Sankyo Kasei) Log 2 with a roll mill at 170℃
The mixture was kneaded for 0 minutes and formed into pellets. This pellet was made into a 1 mm thick sheet by compression molding at 180°C. Pressure and time are each 100kg/cm" 5
It was a minute. When this sheet was placed on a polyester sheet and placed in an oven at 220°C, it foamed in 8 minutes. When this foam was taken out and allowed to cool to room temperature, an open-cell foam with a thickness of 2 mm, an average cell diameter of 0.4 mm, a JIS hardness of 44, and a maximum water absorption of 0.13 g/g without oozing was obtained. It was done.

Propylene with a Melt Index of 10 and a melting point of 145℃
For 100 g of ethylene copolymer, azocica-bonamide foaming agent "Celmic C-2" (foaming temperature 204°C:
(manufactured by Sankyo Kasei) was kneaded for 20 minutes in a roll mill at 150° C., and the mixture was made into pellets. This beret is 170
A sheet having a thickness of 1 mm was formed by compression molding at .degree. The pressure and time were 100 kg/cm" for 5 minutes, respectively. This sheet was placed on a polyester sheet,
When placed in an oven at 220°C, the sheet foamed in 8 minutes, but the air bubbles disappeared and the sheet hardly expanded. When this sheet was allowed to cool to room temperature, it had a thickness of 1.2 mm, an average cell diameter of 0.5 mm, and a JIS hardness of 6.
It was a brittle, closed cell foam of 2.

K-5 ethylene-ethyl acrylate copolymer DPDJ-616
9 (manufactured by Nippon Unicar) 16 kg, dimethylpolysiloxane FZ-3112 (manufactured by Nippon Unicar) 4 kg and 1,1
0.2 kg of 3-tetradecadiene was added to DS2 manufactured by Moriyama Seisakusho.
The mixture was kneaded at 180° C. for 70 minutes using a 0-40 MWA-H type kneader. The rotation speed of the blade was 45 rpm. The gel content of the obtained kneaded product was 24%.

Propylene with melt index lO1 melting point 145°C
For 100 g of ethylene copolymer, 10 g of this kneaded product,
Azocica-bonamide foaming agent "Cellmic C-2J"
(Foaming temperature 204℃: manufactured by Sankyo Kasei) 10g at 150℃
The mixture was kneaded in a roll mill for 20 minutes and pelletized. This pellet was compression molded at 170°C to a size of 1 mm.
It was made into a thick sheet. Pressure and time are 100k each.
g/cm" for 5 minutes. When this sheet was placed on a polyester sheet and placed in an oven at 220°C, it foamed in 8 minutes. When this foam was taken out and allowed to cool to room temperature, Thickness: 2mm, average bubble diameter: 0.
4mm, JIS hardness 40, maximum water absorption rate 0.18g
/g of open-cell foam without exudation was obtained.

Comparison of five ethylene-ethyl acrylate copolymer DPDJ-616
9 (manufactured by Nippon Unicar) 16 kg, dimethylpolysiloxane FZ-3112 (manufactured by Nippon Unicar) 4 kg and 1.1
0.2 kg of 3-tetradecadiene was added to DS2 manufactured by Moriyama Seisakusho.
The mixture was kneaded at 180° C. for 15 minutes using a 0-40 MWA-H type Ni-Goo. The rotation speed of the blade was 45 rpm. The gel content of the obtained kneaded product was less than 10%.

Propylene with a melt index of 10 and a melting point of 145°C
For 100 g of ethylene copolymer, 10 g of this kneaded product,
Azocica-bonamide foaming agent “Celmic C-2J (
Foaming temperature: 204° C. (manufactured by Sankyo Kasei) 10 g was kneaded in a roll mill at 150”C for 20 minutes and pelletized.

This pellet was made into a sheet with a thickness of 1 mm by compression molding at 170°C. Pressure and time are 100 kg each.
/cm" for 5 minutes. This sheet was placed on a polyester sheet, placed in an oven at 220°C, and heated for 7 minutes.
After a few minutes, it was taken out, and a foam with silicone exuding on the surface was obtained.

(Effects of the Invention) In the present invention, since a specific ethylene resin-organopolysiloxane-diene-containing hydrocarbon kneaded product is blended in the foaming of propylene resin, an open-cell propylene resin foam can be obtained; , which has excellent heat resistance, mechanical strength, chemical resistance, water permeability, air permeability, and suitability for construction, has traditionally been used as wire mesh, sintered metal, metal, sintered ceramics, ceramics, foamed metal, and foamed ceramics. It can replace filters made of materials such as zeolite, etc., and is strong against acids and alkalis, making it more durable than the above-mentioned filter materials, and suitable for sewage, sewage, industrial, and food applications. Processability, agricultural use, air conditioning use, household use,
Suitable as a laboratory filter. Other uses include automobile parts, construction materials, and earth materials.

Claims (2)

[Claims] (1) a) 100 parts by weight of a propylene resin, b) 0.1 to 100 parts by weight of an ethylene resin-organopolysiloxane-diene-containing hydrocarbon kneaded product with a gel content of 10% or more, and c) 1 to 30 parts by weight of a blowing agent A composition for non-staining open-cell propylene resin foam, comprising parts by weight. (2) Above b) Ethylene resin with gel content of 10% or more -
The organopolysiloxane-diene-containing hydrocarbon kneaded product contains 10 to 9 parts of organopolysiloxane represented by formula (A) based on 100 parts by weight of ethylene resin.
00 parts by weight R^1_aR^2_bSiO(_4_-_a_-_b_
/_2) (A) (wherein R^1 is an aliphatic unsaturated group, R^
2 is an unsubstituted or substituted monovalent hydrocarbon group containing no aliphatic unsaturated group, 0≦a<1, 0.5<b<3, 1<a+b<3
), (B) 0.01 to 30 parts of a hydrocarbon compound represented by formula CH_2=CH(CH_2)_cCH=CH_2(B)
(wherein c is an integer of 1 to 30) and 0 to 1 part by weight of an organic peroxide, and is obtained by heating and kneading the non-contaminating product according to claim (1). Composition for open cell propylene resin foam.