JPH0662696B2 - Halogenated ultra high molecular weight polyolefin powder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to the tensile strength of a molded article in a wide temperature range,
The present invention relates to a halogenated ultra high molecular weight polyolefin powder having excellent rubber properties such as elongation and flexibility, abrasion resistance, chemical resistance, oil resistance and flame retardancy. Further, the present invention relates to a halogenated ultrahigh molecular weight polyolefin powder having excellent rubber-like properties suitable for use in a molded product containing a filler such as an inorganic filler.

[Conventional technology]

Halogenated polyolefins such as chlorinated polyethylene and chlorinated ethylene / α-olefin copolymers have been conventionally used as rubber elastic bodies with excellent ozone resistance, chemical resistance and oil resistance, but from low temperature to high temperature In applications where rubber properties such as tensile strength, elongation and flexibility in a wide temperature range and abrasion resistance are highly required, these performances are not sufficient, and when an inorganic filler is compounded and used. However, there is a problem that the mixing ratio cannot be increased sufficiently.

[Problems to be solved by the invention]

The present inventors have searched for a halogenated polyolefin which can remedy such drawbacks of conventional halogenated polyolefin such as chlorinated polyethylene, and as a result, have found that halogenated ultra-high molecular weight polyolefin powder having specific properties can be widely used. Rubber properties such as tensile strength, elongation, flexibility of molded products in temperature range, wear resistance, ozone resistance,
The present invention has been accomplished by finding that the oil resistance and flame retardancy are excellent and the above-mentioned object is achieved.

[Means for Solving Problems] and [Action] The present invention has an intrinsic viscosity [η] of 3 dl / g or more measured in o-dichlorobenzene at 135 ° C. and a halogen content of 5 to 60% by weight. %, The average particle size is in the range of 0.1 to 120μ, and the powder with a particle size of 200μ or more is
It is a halogenated ultra high molecular weight polyolefin powder in which 10% by weight or less and 40% by weight or more of the powder in the range of 0.1 to less than 80μ.

The halogenated ultra high molecular weight polyolefin powder of the present invention is
The intrinsic viscosity [η] measured in o-dichlorobenzene at 135 ° C. must be 3 dl / g or more, preferably 10 to 30 dl / g, and more preferably 10 to 20 dl / g. . If the intrinsic viscosity is 3 dl / g or less, the tensile strength and wear resistance of the molded product will be reduced.

The halogen content of the halogenated ultra high molecular weight polyolefin powder according to the present invention must be in the range of 5 to 60% by weight, more preferably 10 to 50% by weight, particularly 20 to 50% by weight.
It is preferably in the range of 45% by weight. When the halogen content is less than 5% by weight, the elongation property, rubber properties such as flexibility, chemical resistance, oil resistance and flame retardancy of the molded article become poor, and the affinity with the inorganic filler becomes poor. As a result, the blending ratio of the inorganic filler is reduced.
If it exceeds 60% by weight, rubber properties such as elongation and flexibility, heat resistance stability, low temperature embrittlement, etc. will be deteriorated. Examples of the halogen contained in the halogenated ultrahigh molecular weight polyolefin powder include fluorine, chlorine, bromine, iodine and the like.

The halogenated ultra high molecular weight polyolefin powder of the present invention is
It has a specific powder property and its average particle size is 0.
It must be in the range of 1 to 120μ, plus 0.
It is preferably in the range of 1 to 80μ, particularly 0.1 to 50μ. When the average particle size is larger than 120μ, the packing property of the inorganic filler is lowered, and the difference in the halogen content distribution in the radial direction of the particles during the halogenation reaction is likely to be large, which results in rubber-like properties such as flexibility. , Heat resistance stability, low temperature embrittlement, etc. are also reduced, and if it is less than 0.1 μ, cohesive force becomes strong and the dispersibility of the filler decreases, causing the danger of powder explosion in air. In addition, the safety when handling becomes poor.

Further, the particle size distribution of the halogenated ultra high molecular weight polyolefin powder is such that the powder having a particle size of 200 μ or more is 10% by weight or less of the whole and the powder having a particle size in the range of 0.1 to less than 80 μ is 6% of the whole.
It must be 0% by weight or more, and the particle size is 2
Less than 5% by weight of powder of 50μ or more and 0.5 to 60
The powder in the range of less than μ is preferably 80% by weight or more of the whole. 10% by weight of the total content of particles with a particle size of 200μ or more
When the content of the powder is larger and the content of the powder in the range of 0.1 to less than 80 μ is less than 40% by weight, the filling property of the inorganic filler is lowered, and the difference in the halogen content distribution in the particle radial direction during the halogenation reaction is large. Therefore, rubber properties such as flexibility, heat resistance, low temperature embrittlement, etc. are also deteriorated. Here, the average particle size and particle size distribution of the halogenated ultra high molecular weight polyolefin powder are measured by Coulter Counter TAII type.

The bulk density of the halogenated ultrahigh molecular weight polyolefin powder is usually required to be in the range of 0.1 to 0.3 g / cm ³ , and more preferably 0.15 to 0.25 g / cm ³ .

The halogenated ultra high molecular weight polyolefin powder of the present invention is
It can be prepared by halogenating the corresponding ultra high molecular weight polyolefin powder. Here, the ultrahigh molecular weight polyolefin used as a raw material is polyethylene, polypropylene, poly 1-butene, poly 4-methyl-
Besides α-olefin homopolymers such as pentene, ethylene, propylene, 1-butene, 1-hexene, 1-
It also includes a copolymer of two or more α-olefins such as octene and 1-decene, and the intrinsic viscosity [η] measured in decalin at 135 ° C. is usually 5 to 30 dl / g, preferably 10 to It is in the range of 30 dl / g. The average particle size of the ultra high molecular weight polyolefin powder is usually 0.1.
To 100μ, preferably 0.1 to 80μ, especially 0.1 to 50μ, and its particle size distribution is such that the powder having a particle size of 200μ or more is usually 10% by weight or less, preferably 5% by weight or less, and 0.1 The total powder content is usually 40% by weight or more, preferably 80% by weight or more, and the bulk density is usually 0.1 to 0.3 g / cm 3.
³ , preferably in the range of 0.15 to 0.25 g / cm ³ .

Examples of the method for halogenating the ultrahigh molecular weight polyolefin powder include a method in which a suspension of the ultrahigh molecular weight polyolefin powder dispersed in a medium is reacted with a halogenating agent in the presence of a catalyst, if necessary. can do.
Examples of the medium include water, methylene chloride, chloroform, dichloroethane, trichloroethane, perfluorodecane, hexafluorobenzene, halogenated hydrocarbons such as perfluorodecalin, and the like. As the halogenating agent, in addition to molecular halogen such as fluorine, chlorine, bromine or iodine, sulfuryl chloride or the like can be used. The use ratio is an appropriate amount within the range where the halogen content of the halogenated ultrahigh molecular weight polyolefin powder produced by the halogenation reaction reaches the above range. The temperature during the halogenation reaction is 50 to 160 ° C, preferably 8
It is in the range of 0 to 150 ° C. The halogenated ultra high molecular weight polyolefin powder can be obtained by filtering the halogenated ultra high molecular weight polyolefin powder from the suspension after the reaction, washing and drying.

The halogenated ultra-high molecular weight polyolefin powder of the present invention can be molded without blending an inorganic filler, but in the case of molding with an inorganic filler, even if a large amount is blended, the tensile strength is increased. It is preferable because a molded product having excellent surface smoothness can be obtained without lowering properties such as rubber properties such as elongation rate and flexibility, abrasion resistance, chemical resistance, oil resistance and the like. When the inorganic filler is compounded, the compounding ratio is usually 5 to 1500 parts by weight, preferably 10 to 1000 parts by weight, based on 100 parts by weight of the halogenated ultrahigh molecular weight polyolefin powder.

Specific examples of the inorganic filler include calcium carbonate, talc, clay, silica, aluminum hydroxide, ferrite, carbon black, antimony trioxide, calcium silicate, barium sulfate and titania. Further, the halogenated ultrahigh molecular weight polyolefin powder of the present invention can be processed without adding a crosslinking agent at the time of molding, or can be processed by adding a crosslinking agent. As the cross-linking agent, it is possible to use a cross-linking agent which is conventionally blended with halogenated polyolefin. Specific examples of the cross-linking agent include dicumyl peroxide, 1,1-di (tert-butylperoxy) -3,3,5-tolumethylcyclohexane, 2,5-dimethyl-2,5-di (tert-butylperoxy). ) Organic peroxides such as hexane, 2,4,6-trimercapto-s-triazine, triazine compounds such as 2-phenylamino-4,6-dimercapto-s-triazine, trithiocyanuric acid, sulfur, sulfur chloride, Sulfur dichloride,
Examples thereof include sulfur compounds such as morpholine disulphide and alkylphenol disulphide.
The mixing ratio is appropriate.

〔Example〕

 Next, the present invention will be specifically described with reference to examples.

Example 1 In a polymerization vessel having an internal volume of 2750, n-decane 1500, triethylaluminum 1500 mmol and particulate titanium catalyst component 15
mmol was added and the temperature was raised to 70 ° C. After that, ethylene gas was introduced into the polymerization vessel at a rate of ³⁰ NM ³ / Hr. Polymerization pressure is 1
It was ~ 6 kg / cm ³ G.

When the cumulative amount of ethylene introduced reached 180 NM ³ , ethylene was fed cut, and after 10 minutes of post-polymerization, cooling depressurization was carried out to obtain a slurry of ultrahigh molecular weight polyethylene. The slurry was subjected to high-speed shearing treatment of the slurry for 1 hour using a commercially available homomic line mill. The obtained polymer and solvent were separated by a centrifuge,
Drying under reduced pressure was carried out under a N ₂ gas stream at ° C.

The yield of the obtained polymer was 255 kg, the molecular weight was 23.3 dl / g as the intrinsic viscosity measured in decalin at 135 ° C, and the average particle size was D.
_{At 50} 26 μm, the particle size distribution passed 100 mesh in all, and passed 350 mesh in 85%.

Fine particle ultra high molecular weight polyethylene obtained by the above method
200 g, distilled water 4, 60 mg of TW-80 surfactant (trade name of Dai-ichi Kogyo Seiyaku Co., Ltd.) in 5 reactors equipped with a reflux condenser, stirrer, thermometer, chlorine gas blowing pipe, etc. added.
While stirring, chlorine gas was blown at a rate of 20 / Hr at atmospheric pressure to carry out a 3.5Hr chlorination reaction at 90 ° C. After completion of the reaction, the temperature was lowered to room temperature and the aqueous phase was neutralized with aqueous NaOH. After neutralization, the chlorinated ultra high molecular weight polyethylene powder was filtered off with a glass filter, and this powder was washed with distilled water of 3 and filtered off a total of 3 times. Then, it was dried in a vacuum dryer under the conditions of 70 ° C. and 10 mmHg to obtain 266 g of white chlorinated ultra high molecular weight polyethylene powder. The chlorine content of this powder was 15.9 dl / g with an intrinsic viscosity measured in 25.1 wt% o-dichlorobenzene, with an average particle size of D ₅₀ 29 μm and a particle size of 200 μm or more.
The amount of powder was 0.9 wt% and the particle size was in the range of 0.1 to less than 80 μm, which was 91% by weight of the whole.

Example 2 In the same manner as in Example 1, ethylene was polymerized at a temperature of 80 ° C. to obtain a small spherical polyethylene of [η] 15.7 dl / g (intrinsic viscosity measured in decalin at 135 ° C.). Average particle size is D
_The size was ₅₀ 23 μm, and 100 mesh pass all the amount, and 350 mesh flow passed 86%.

This particulate ultra high molecular weight polyethylene was subjected to a 2Hr chlorination reaction at 105 ° C. under pressure in the same apparatus as in Example 1,
Neutralized, washed and dried to give a chlorine content of 29.9 wt%, an intrinsic viscosity measured in o-dichlorobenzene of 10.5 dl / g, an average particle size D _{50 of} 27 μm and a particle size of 200 μm or more is 2.5 wt% of the total.
Thus, 87% by weight of the powder having a particle size in the range of 0.1 to less than 80 μm was obtained to obtain a chlorinated ultra high molecular weight polyethylene powder.

Example 3 [η] 12.1 dl / g, D ₅₀ 40μ using the fine particle catalyst obtained by high-speed shearing using a homomixer in the state of hexane slurry as a catalyst in the same manner as in Example 1.
m, 100% mesh sieve 61% passed, 350 mesh sieve 56% passed to obtain a particulate ultra high molecular weight polyethylene.

This was chlorinated in the same manner as in Example 2 to give a chlorine content of 3
7.4d with intrinsic viscosity measured in 5.2wt, o-dichlorobenzene
l / g, average particle size D ₅₀ 46 μm, powder with a particle size of 200 μm or more is 3.7 wt% of the whole, and powder with a particle size in the range of 0.1 to less than 80 μm is 84 wt% of the total chlorinated ultra high molecular weight polyethylene powder Got

Example 4 In the same manner as in Example 2, 23 mmol of titanium catalyst component was added.
Polymerization of ethylene at a temperature of ℃, [η] 22.3dl / g
(In decalin, 135 ° C.), average particle size D _50: 31 μm, 100 mesh sieve was passed through the entire amount, and 350 mesh sieve was passed through 68% to obtain a particulate ultra high molecular weight polyethylene.

This was chlorinated in the same manner as in Example 2 to give a chlorine content of 3
3.4 wt%, 1 at the intrinsic viscosity measured in o-dichlorobenzene
Chlorinated ultra-high molecular weight polyethylene with a powder of 4.3 dl / g, an average particle size D _{50 of} 35 μm and a particle size of 200 μm or more is 1.4 wt% of the whole, and a powder with a particle size of 0.1 to less than 80 μm is 88 wt% of the whole. A powder was obtained.

Comparative Example 1 A low-pressure high-density polyethylene powder having an intrinsic viscosity of 2.3 dl / g (in decalin at 135 ° C.) and an average particle diameter D _{50 of} 400 μm was chlorinated in the same manner as in Example 2. The chlorine content of this powder is 30.3wt
%, The intrinsic viscosity measured in o-dichlorobenzene is 1.6 dl
/ G, the average particle size was D ₅₀ 450 μm, and the particle size was 200 μm or more was 83 wt% of the whole powder, and the particle size range of 0.1 to less than 80 μm was 12 wt% of the whole powder.

Comparative Example 2 Example 1 except that chlorine gas was blown at a rate of 20 / Hr and the chlorination reaction was carried out at 90 ° C. and 0.5 Hr.
A chlorinated ultra high molecular weight polyethylene powder was obtained in the same manner as in (1). The chlorine content of this powder was 4 wt%, the intrinsic viscosity measured in o-dichlorobenzene was 22.1 dl / g, the average particle size was D ₅₀ 26.
0.7 wt% of the powder with a particle size of 200 μ or more in μm,
93wt% of powder with particle size ranging from 0.1 to less than 80μm
It was in%.

Comparative Example 3 Example 1 except that the chlorinated gas was blown at a rate of 20 / Hr to carry out the chlorination reaction at 90 ° C. and 8 Hr.
A test was carried out in the same manner as in 1. to obtain a chlorinated ultra high molecular weight polyethylene powder. The chlorine content of this powder is 62 wt%, the intrinsic viscosity measured in o-dichlorobenzene is 7.5 dl / g, the average particle size is 31 μm, and the powder with a particle size of 200 μm or more is 1.7 wt% of the whole.
And 81% by weight of the total amount of powder having a particle size in the range of 0.1 to less than 80 μm.

Comparative Example 4 Polyethylene powder having an intrinsic viscosity (in decalin, 135 ° C.), 16.5 dl / g, and an average particle diameter D _{50 of} 200 μm (trade name: Hi-Zex Million 240M, manufactured by Mitsui Petrochemical Co., Ltd.) was used as in Example 2. Chlorinated. The chlorine content was 31.7 wt%, the intrinsic viscosity measured in o-dichlorobenzene was 10.7 dl / g, the average particle size was D ₅₀ 230 μm, and the powder with a particle size of 200 μm or more was the whole.
A powder having a particle size of 61 wt% and a particle size in the range of 0.1 to less than 80 μm was obtained in a total amount of 1.5 wt%.

Evaluation Examples 1 to 8 The chlorinated polyethylene powder obtained in each of the examples and comparative examples and barium ferrite were blended at a weight ratio of 100: 900 and press-molded to obtain a 10 mm-thick press sheet. The result of cutting this and measuring the physical properties is summarized in Table 1. However, the shear and the wear amount are the measurement results when the graphite carbon was not blended.

Tensile test method Test piece; ASTM No. 4 dumbbell x 2mm thickness Tensile speed; 50mm / min Tensile tester; Instron TTM type shear hardness JIS K-6301 spring type hardness test (A type).

Abrasion amount Taber abrasion test According to JIS-K-6902.

H-22 was used as the wear wheel, and the wear amount (mg) of 1000 rotating bodies was obtained.

Evaluation Example 9 The chlorinated ultra high molecular weight polyethylene powder obtained in Example 2 was mixed with a 10 Hensiel mixer (manufactured by Mitsui Miike Seisakusho Co., Ltd.) according to the formulation shown in Table 2 below.

The Hensiel mixer was heated to 70 ° C., and carbon black and oil were added little by little to the chlorinated ultra high molecular weight polyethylene powder over 10 minutes while repeating stirring. Then, other compounding agents were added and stirred for 1 minute. The mixture is powdery, despite the addition of large amounts of oil,
It was easy to handle.

This compound was kneaded with an 8-inch mill roll (manufactured by Terakawa Seisakusho, roll surface temperature front / back = 60/70 ° C.) for 5 minutes. The kneaded product was taken out in a sheet form and subjected to vulcanization. Vulcanization was carried out at 150 ° C. for 30 minutes with a 150 t steam press to obtain a vulcanized sheet having a thickness of 2 mm.

Using this vulcanized sheet, according to JIS K6301, tensile strength,
The elongation and spring hardness were measured. The results are shown in Table 3.

Evaluation Example 10 Evaluation was made in the same manner as in Evaluation Example 9 except that the chlorinated polyethylene obtained in Comparative Example 1 was used in place of the chlorinated ultra high molecular weight polyethylene powder.

The formulation mixed with the Hensiel mixer was sticky, did not form a powder, and was inconvenient to handle. Table 3 shows the measurement results.
Shown in.

Evaluation Example 11 Evaluation was carried out in the same procedure as in Evaluation Example 9 except that the chlorinated polyethylene obtained in Comparative Example 2 was used in place of the chlorinated ultrahigh molecular weight polyethylene powder in Evaluation Example 9. Processing with rolls was impossible.

Evaluation Example 12 Evaluation was carried out in the same procedure as in Evaluation Example 9 except that the chlorinated polyethylene obtained in Comparative Example 3 was used in place of the chlorinated ultrahigh molecular weight polyethylene powder in Evaluation Example 9. Processing with rolls was impossible.

Evaluation Example 13 Evaluation was carried out in the same procedure as in Formulation Example 9 except that the chlorinated ultra high molecular weight polyethylene powder obtained in Comparative Example 4 was used in place of the chlorinated ultra high molecular weight polyethylene powder in Evaluation Example 9. The formulation mixed with the Hensiel mixer was sticky, did not form a powder, and was inconvenient to handle.

Claims (1)

[Claims] 1. An intrinsic viscosity [η] measured in o-dichlorobenzene at 135 ° C. is 3 dl / g or more, a halogen content is in the range of 5 to 60% by weight, and an average particle size is 0.1 to 120 μm. And the powder with a particle size of 200μ or more
A halogenated ultra high molecular weight polyolefin powder, which is 10% by weight or less and 40% by weight or more of the total powder in the range of 0.1 to less than 80 μ.