JPH0138407B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a chlorosulfonated polyolefin that has both good mechanical properties and low-temperature properties as a vulcanizate. Conventionally, vulcanized products of chlorosulfonated polyethylene have excellent mechanical strength properties, ozone resistance, chemical resistance, flame retardance, and coloring properties, so they have been used for hoses, canvas, electric wires, paints, and various industrial materials. has been done.
However, the properties of the vulcanizate differ depending on the polyethylene used as the raw material. For example, chlorosulfonated polyethylene made from branched low-density polyethylene produced by a high-pressure method has a low mechanical strength.
On the other hand, chlorosulfonated polyethylene, which is made from linear high-density polyethylene produced by a low-pressure process, has good mechanical properties as a vulcanizate, but has poor low-temperature properties, which is a problem especially when used in cold regions. It has been desired to develop a chlorosulfonated polyolefin that has high mechanical strength due to its sulfur content and excellent low-temperature properties. An object of the present invention is to obtain a chlorosulfonated polyolefin that provides a vulcanizate that has high mechanical strength and excellent low-temperature properties without impairing other excellent properties. The method for producing a chlorosulfonated polyolefin of the present invention is characterized by chlorosulfonating a linear copolymer of ethylene and α-olefin having a density of less than 0.93 g/cc. Generally, Linear Low Density Polyethylene
The present invention also includes the use of a polymer called LLDPE having a density of less than 0.93 g/cc as a raw material. These copolymers can be obtained, for example, by copolymerizing ethylene and α-olefin in the presence of a transition metal complex catalyst. -There is olefin. Examples include propylene,
1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 3-methyl-1-pentene, 4-methyl-1-pentene, 1-heptene,
1-octene, 1-decene, 1-dodecene, 1-
Examples include tetradecene and 1-octadecene, but normal α-olefin is preferable, and normal 1-butene is particularly preferable. Regarding linear copolymers of ethylene and α-olefin, there are currently no commercially available linear copolymers with a density of 0.90 g/cc or less. Propylene, 1 as the α-olefin in the copolymer with a density of 0.93 g/cc to 0.90 g/cc
In the case of -butene and 4-methyl-1-pentene, the copolymerization ratio was analyzed by ¹³ C-NMR,
If the number of methyl groups, ethyl groups, and isobutyl groups are calculated per 1000 carbon atoms, and the correlation with the density is calculated, the amounts will be as shown in the table below, but the present invention is not limited to the above density range. do not have.

[Table] Also, the melt index of the copolymer (hereinafter
(abbreviated as MI) was measured according to JIS K7210,
Preferably it is in the range of MI1-50. When MI is 1 or less and 50 or more, the compounding processability of the obtained chlorosulfonated polyolefin deteriorates, but the present invention is not limited to the above range. A known method can be used for chlorsulfonation. First, a linear copolymer of ethylene and other α-olefins is uniformly dissolved in an organic solvent. The dissolved concentration is preferably 2 to 20 parts by weight, particularly preferably 5 to 10 parts by weight, per 100 parts by weight of the solvent.
The solvent is one that dissolves the polymer and is inert to the reaction initiator and reactant chlorine, sulfur dioxide gas, and sulfuryl chloride, such as carbon tetrachloride,
methylene chloride, chloroform, ethylene trichloride,
Chlorinated benzene, tetrachloroethane, dichlorofluoromethane, benzene, etc. can be used, but
Carbon tetrachloride is preferred. The reaction is carried out by introducing sulfuryl chloride, chlorine and sulfuryl chloride, or chlorine and sulfur dioxide gas into the reaction system in the presence of a radical reaction initiator. Preferably, these reactants are introduced continuously. Catalysts or radical reaction initiators used include α,α′-azobisisobutyronitrile, azodicyclohexenecarbonitrile, 2-(2′-
These include azobis(cyanoalkanes) such as hydroxyethylazo)-2,4-dimethylvaleronitrile and organic peroxides such as lauroyl peroxide or di-t-butyl peroxide. Also, as cocatalysts, certain tertiary amines such as pyridine, quinoline, quinaldine, nicotine, piperidine, dimethylaniline, and tributylamine; certain sulfhydryl compounds such as 2-mercaptothiazoline and allylthiourea; and dimethylformamide and dimethyl The use of amides such as acetamide accelerates the chlorosulfonation reaction. Moreover, light, especially ultraviolet light, can also be used as a radical reaction initiator. The reaction conditions include a temperature of 65-120°C, especially 90-120°C.
110℃, normal pressure ~5Kg/ ^cm2G , especially 1.5~3Kg/
cm ² G is preferable in order to maintain the polymer at a temperature higher than the melting temperature and cause the reaction to occur uniformly. The chlorsulfonation is carried out until 0.1 to 4% by weight of sulfur, preferably 0.7 to 1.8% by weight; and 15 to 50% by weight, preferably 25 to 45% by weight of chlorine are present in the resulting chlorosulfonated polyolefin, respectively. Carry out the reaction. The produced chlorosulfonated polyolefin is separated from the reaction solution and dried. Separation and drying methods include (1) charging the reaction solution in a poor solvent for chlorosulfonated polyethylene such as methanol and ethanol to insolubilize the polymer, separating and drying the precipitate; (2) reaction A method in which the polymer is dispersed in hot water by feeding the liquid into hot water, while the solvent is steam-distilled to separate and dry the polymer. (3) The reaction solution is fed onto the surface of a heated rotating drum. (4) Concentrate the reaction solution if necessary and feed it to a vented extruder to take out the dry polymer. There are several methods, all of which can be used. The obtained chlorosulfonated polyolefin is suitably blended and vulcanized to produce a vulcanizate.
A vulcanizing agent is an essential component of the compounding agents added to chlorosulfonated polyolefin, and in addition, vulcanizing accelerators, reinforcing agents, fillers, plasticizers, softeners, anti-aging agents, processing aids, and coloring agents are also included. There are other rubber chemicals. Vulcanizing agents include metal oxides such as magnesia, litharge, tribasic lead maleate, and dibasic lead phosphite, bisphenol epoxy resins, and polyhydric alcohols such as pentaerythritol; vulcanization accelerators include , TRA (dipentamethylenethiuram tetrasulfide), TET (tetraethylthiuram,
disulfide), thiuram series such as TT (tetramethylthiuram disulfide), thiazole series such as DM (dibenzothiazyl disulfide) and M (2-mercaptobenzothiazole), sulfur, ethylenethiourea, etc., and ordinary chlorosulfonated polyethylene. You can use what is used for. Further, the total amount of these used may be 1 to 30 parts by weight; if it is too small, vulcanization will not occur, and if it is too large, it will not be good. As reinforcing agents and fillers, carbon black,
Silica, clay, calcium carbonate, titanium oxide,
Organic reinforcing agents such as high styrene resin, talc, diatomaceous earth, mica powder, asbestos, aluminum sulfate, barium sulfate, calcium sulfate, glass fiber, wood flour, etc., and as plasticizers and softeners, phthalic acid derivatives, adipine, etc. Acid derivatives, sebacic acid derivatives, etc.
In addition, petroleum-based softeners, vegetable oil-based softeners, Factis, etc., and anti-aging agents such as naphthylamine-based, P-phenylenediamine-based, hindered phenol-based, NBC (nickel dibutyl dithiocarbamate), etc. In addition, processing aids include stearic acid, waxes, low molecular weight polyethylene, etc., and coloring agents include inorganic and organic sulfur, etc.
Those used in ordinary chlorosulfonated polyethylene can be optionally added and used, but these are not limited to the above. The rubber compound thus obtained is usually 120
The rubber vulcanizate obtained is vulcanized at ~200℃.
It has excellent low-temperature properties without sacrificing the properties of conventional chlorosulfonated polyethylene rubber vulcanizates. EXAMPLES In order to explain the present invention more specifically, Examples are shown below. Example 1 500 kg of carbon tetrachloride in a reaction vessel and a density of 0.925 g/
Linear copolymer of ethylene and normal 1-butene with cc and MI of 4 (manufactured by Mitsui Petrochemical Industries, Ltd., trade name)
Neozex2540R) 40Kg and nitrogen to 1Kg/
After pressurizing to cm ² (gauge), the linear copolymer was dissolved by stirring while increasing the internal temperature to 100°C. In this dissolved solution, 100 g of α,α′-azobisisobutyronitrile was dissolved and 1200 g of carbon tetrachloride was added.
After adding cc and 5g of pyridine, chlorine gas was added at 15% per minute.
g, sulfuryl chloride at a feed rate of 330 g/min 4
The mixture was introduced into the reactor for a time, and the reaction was allowed to proceed. During this reaction, the temperature starts at 100℃ and gradually decreases to 80℃, and the pressure also starts at 1.70Kg/cm ² (gauge), with a final pressure of 0.8Kg/cm ² (gauge). operated on. Hydrogen chloride and sulfur dioxide gases generated as the reaction progressed were neutralized and removed using a 10% caustic soda aqueous solution. The solid content of the reaction-completed liquid was 11.5% by weight. This reaction solution was heated to 150°C, fed into a container with a reduced pressure of 50 mmHg abs, and the solid content was 40% by weight.
This polymer solution was introduced into a vented extruder and extruded under reduced pressure at a cylinder temperature of 100 to 160°C to obtain a dry chlorosulfonated polyolefin (polymer A). The chlorine and sulfur content of this polymer was determined by elemental analysis. Using this chlorosulfonated polyolefin, it was compounded according to the following formulation, then vulcanized, and the physical properties of the vulcanized product were measured. Formula parts by weight Chlorsulfonated polyethylene 100 Stearic acid 3 Magnesia 20 Dipentamethylene lentithuram detrasulfide
2 Vulcanization conditions: 160°C x 20 minutes The results are shown in Table 1. Example 2 Chlorosulfonated polyolefin ( obtaining polymer B),
Then, they were mixed in the same manner, vulcanized, and the physical properties of the vulcanized product were measured. The results are shown in Table 1. Comparative Example 1 Using high-pressure branched low-density polyethylene (manufactured by Sumitomo Chemical Co., Ltd., trade name Sumikasen F702-3) with a density of 0.922 g/cc and an MI of 7, chlorsulfonation was performed in the same manner as in Example 1. Polyethylene (polymer C)
was obtained, and then blended in the same manner, vulcanized, and the physical properties of the vulcanized product were measured. The results are shown in Table 1. Comparative Example 2 Chlorosulfonated polyethylene was produced in the same manner as in Example 1 using low-pressure normal high-density polyethylene (manufactured by Mitsui Petrochemical Industries, Ltd., trade name Hi-Zex 2100J) with a density of 0.957 g/cc and an MI of 6. (Polymer D)
was obtained, then mixed in the same manner, vulcanized, and the physical properties of the vulcanized product were measured. The results are shown in Table 1. Comparative Example 3 Using low-pressure normal high-density polyethylene (manufactured by Mitsubishi Yuka Co., Ltd., trade name Yucalon Hard JX-20) with a density of 0.964 g/cc and an MI of 6, chlorsulfone was added in the same manner as in Example 1. Polyethylene (Polymer E) was obtained, and then compounded in the same manner, vulcanized, and the physical properties of the vulcanized product were measured. The results are shown in Table 1. Comparative Example 4 Furthermore, Hypalon #40 (Polymer F) and Hypalon #20 (Polymer G), which are commercially available chlorosulfonated polyethylenes, were blended and vulcanized in the same manner as in Example 1 to obtain a vulcanized product. Physical properties were measured.

[Table] Example 3 Using Polymer A obtained by the method described in Example 1, Polymer D according to Comparative Example 2, and Polymer F according to Comparative Example 4, they were blended according to the following formulation, and then added. Curing was carried out and the physical properties of the vulcanized product were measured. The measurement results are shown in Table 2. Formula parts by weight Chlorsulfonated polyethylene 100 Stearic acid 3 SRF Carbon Black 50 Aromatic oil 10 Resurge 25 Dipentamethylene thiuram tetrasulfide
2 Dibenzothiazyl disulfide 0.5 Vulcanization conditions 160℃ x 10 minutes

【table】

Claims (1)

[Claims] 1 Ethylene and α- with a density of less than 0.93 g/cc
A method for producing a chlorosulfonated polyolefin, which comprises chlorosulfonating a linear copolymer with an olefin.