JPH0365373B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for pulverizing a polymeric material.
More specifically, the present invention relates to a method in which a polymeric material having a reactive functional group is treated with a compound having two or more functional groups that react with the functional group, heated to cause a crosslinking reaction, and then pulverized. Fine powder of polymeric materials has conventionally been used in various ways. One of them is a filler (also an extender) for thermosetting resins. For example, when a molded article is manufactured using a phenolic resin or a urea resin, a large amount of filler made of a polymeric material, such as wood flour, coconut shell powder, or pulp powder, is blended. In recent years, large amounts of fillers made of polymeric materials have come to be blended not only with thermosetting resins but also with thermoplastic resins as needed. In order to produce a fine powder of a cellulosic polymer material as described above, the usual method is to dry and mechanically crush the material. However, this method has the drawback of low pulverization efficiency and high power consumption. The following methods have been proposed to overcome this drawback. In other words, a. A method of adding an appropriate amount of an inorganic acid, alkali, or salt to the material during pulverization, and washing the pulverized material after pulverization to remove the inorganic acid, etc. A method of using a nonionic surfactant as a grinding aid (Japanese Patent Publication No. 1141/1983), c. A method of using higher fatty acids, their alkali salts or their alkaline earth metal salts (Special Publication No. 50-1142)
No.) has been proposed. Also, d. Method of pulverizing an object after irradiating it with radiation (Special Publication No. 1972-23540)
There is also. However, the above-mentioned methods 1 to 3 still have insufficient pulverization effect, and the above-mentioned methods 2. The method requires separate irradiation equipment and also significantly reduces the degree of polymerization of the finely pulverized product. "Polymer materials with reactive groups" that require pulverization are not limited to cellulose-based materials; vegetable materials include rice, shells such as corn, potatoes such as potatoes and sweet potatoes, various starchy materials, and There are pectic materials such as citrus peel. In addition, animal materials include leather materials, casein, glue,
Includes gelatin, dried fish, dried pupae, or dried animal meat. Examples of other biological materials include useful substances such as dried seaweed, mushrooms, and chlorella, as well as surplus sludge generated when various types of wastewater are treated by activated septic methods. Furthermore, among synthetic polymer materials, there are various types of thermosetting and thermoplastic plastic molded products, and waste materials after use of defective products during the production of synthetic fibers, such as phenolic resins, urea resins, polyvinyl alcohols, and the like. The present inventor has conducted extensive research into methods for efficiently pulverizing animals, plants, other biological materials, or synthetic polymeric materials having reactive functional groups as described above. As a result, if these materials are treated with a certain cross-linking agent, heated to cause a cross-linking reaction, and then pulverized, the pulverization efficiency will be dramatically improved compared to untreated materials or those treated with known methods, and it will be possible to achieve various desired purposes. The present invention was completed knowing that it is possible to achieve pulverization of materials. As is clear from the above description, the objects of the present invention are a method for efficiently processing a polymeric material having a reactive functional group (hereinafter sometimes referred to as "reactive polymeric material"), and a method for efficiently processing a polymeric material having a reactive functional group, and a method for efficiently processing a polymeric material having a reactive functional group. The purpose of the present invention is to provide a fine powder of a polymeric material. Other purposes will become clear from the description below. (1) A polymeric material having a reactive functional group has a general formula that has two or more functional groups that react with the functional group.

[Formula] (A or B is H, alkyl having 1 to 12 carbon atoms, or aralkyl having 7 to 12 carbon atoms, respectively) After treatment with a compound, heating to cause a crosslinking reaction and pulverizing the crosslinked reaction product A method for pulverizing a polymeric material, characterized by: (2) PH processing of polymeric materials with reactive functional groups
The pulverization method according to the above item 1, which is carried out at a temperature of 7 or less. (3) The pulverization method according to item 1 above, wherein the polymeric material having a reactive functional group is treated in the presence of a catalytic amount of a metal salt, ammonium salt or amine salt of a strong acid. (3) PH processing of polymeric materials with reactive functional groups
The pulverization method according to the above item 1, which is carried out at a temperature of 7 or less. (4) The pulverization method according to item (1) above, wherein the polymeric material having a reactive functional group is treated in the presence of a catalytic amount of a metal salt, ammonium salt, or amine salt of a strong acid. The structure and effects of the present invention will be explained in detail below. As mentioned above, the polymeric materials having reactive functional groups used in the present invention include animal, vegetable or other biological materials, and various synthetic polymeric materials.
In order to facilitate treatment with a compound having two or more functional groups as described below, these materials are pre-cut into appropriate shapes and dimensions, or pre-pulverized, or dried, humidified, or heat-treated as necessary. Suitable shapes for treatment with compounds having two or more functional groups according to the present invention include small particles, powder, flakes, fibrils, and the like. Therefore, for example, regarding cellulose-based materials, materials that can be crushed, such as coconut shells, are coarsely crushed to a particle size of about 5 mm to 10 mm, and materials that can be cut, such as pulp, are cut to a similar size. On the other hand, wood flour such as sawdust can be used as is for crosslinking treatment. Compounds having two or more functional groups that react with the reactive functional groups of the reactive polymeric material used in the present invention (hereinafter referred to as the crosslinking agent according to the present invention) include the treatment and heating described below for the material. The higher the crosslinking density of the crosslinked and cured product, the more effective it is when used in a small amount. Examples of such crosslinking agents according to the present invention include glyoxal and methylglyoxal. In the present invention, the treatment of the reactive polymer material with the crosslinking agent is preferably carried out by immersing the material in an aqueous solution of the crosslinking agent, or by sprinkling or spraying the aqueous solution onto the surface of the material. The agent is infiltrated into the reactive polymeric material. Therefore, adjusting the shape and dimensions of the material as described above is a desirable additional step to the crosslinking agent treatment step of the present invention. The concentration of the aqueous crosslinking agent solution is not limited, but is preferably 0.5 to 90% by weight, preferably 1 to 70% by weight.
%. Further, conditions such as immersion are not limited, but immersion is carried out at 0 to 40°C for 0.5 minutes to 100 hours, preferably for 5 minutes to 50 hours. During immersion, it is necessary that the immersion liquid sufficiently penetrate into the inside of the object to be treated. Therefore, when processing porous materials, a small amount of surfactant may be added to the immersion liquid, or immersion may be performed under reduced pressure or increased pressure. The temperature of the immersion treatment is not limited, but is preferably 0 to 100°C.
It can be carried out at ℃. In the above-mentioned immersion treatment according to the present invention, it is necessary to set the pH of the immersion liquid to 7 or less in order to promote crosslinking in the heat treatment (crosslinking reaction) described below. For pH adjustment, use various acids, especially inorganic acids such as sulfuric acid, phosphoric acid, hydrochloric acid, nitric acid, sulfamic acid, or formic acid, acetic acid,
This is done by adding an organic acid such as propionic acid. In place of these acids, ammonium salts of strong acids such as ammonium chloride, ammonium sulfate, ammonium phosphate, and alkanolamine hydrochlorides or hydrochlorides of organic amines can be used. Metal salts of strong acids such as zinc chloride, magnesium chloride, zinc sulfate, aluminum sulfate, and magnesium dihydrogen phosphate can also be used. It is sufficient to use these acids, ammonium salts of acids, amine hydrochlorides, or metal salts of strong acids in such amounts that the pH of the immersion liquid is kept at 7 or less, in other words, in so-called catalytic amounts. In the present invention, the heat treatment includes, after treatment with the above-mentioned crosslinking agent, causing the crosslinking agent to undergo a crosslinking reaction with a reactive polymer material;
This step is to facilitate the pulverization of the material after the crosslinking. By this heating, water as a solvent of the above-mentioned crosslinking agent can be evaporated and dried simultaneously with the crosslinking reaction or before the start of the crosslinking reaction. Heating conditions are not limited, but usually 70 to 200
The necessary heat treatment can be completed in 0.5 to 3 hours at 120°C for 5 minutes, for example. Reactive polymer material after heating following the above treatment (hereinafter referred to as crosslinked polymer material)
is then pulverized which is subjected to a grinding process. The pulverizer used and the pulverizing conditions are the same as in the case of known pulverization of inorganic powders. That is,
The granular crosslinked polymer material according to the present invention is processed using a ball mill, tube mill, rod mill, vibration mill, etc. at 0°C to 100°C, preferably room temperature to 50°C, for 1 minute to 3 hours, preferably 1 minute to 1 hour. is easily pulverized to a particle size of 0.01 to 1 mm. The following four main effects of the method of the present invention are listed below. That is, firstly, since the crushing efficiency is improved, the power (energy) for crushing can be greatly saved. Second, fine powder can be easily obtained (note: high pulverization efficiency). Therefore, it becomes possible to use it as a resource for pulverizing reactive polymer materials, which have been difficult to pulverize in the past. Specific examples of such materials include fast-growing plant materials such as poplar, various South Sea woods, and bamboo. Thirdly, the method of the present invention is useful as a method for processing so-called industrial or domestic waste, or a method for enabling post-processing utilization (recycling). According to the method of the present invention, it is possible to treat and recycle, for example, sawdust, rice husk, used paper, (organic) waste from pulp mills, or surplus sludge. In addition, the present invention also enables the immobilization and pulverization of hemicellulose or lignin, which is essentially unusable in the pulp industry. Fourthly, the fine powder obtained by the method of the present invention has good physical properties and is therefore useful as a filler or extender for various purposes such as plastics, building materials, civil engineering, etc. Such improved physical properties include improved water resistance and chemical resistance (compared to untreated powder). In addition, depending on the type of the reactive polymer material according to the present invention, the treatment of the present invention may generate nitrogen-containing low molecules such as ammonia and amines, or sulfur-containing low molecular compounds such as hydrogen sulfide or mercaptan. Since it captures and deodorizes waste, it is useful as a method for processing and recycling waste related to these odors. The structure and effects of the present invention are shown below in Examples and Comparative Examples. Example 1 100g of sawdust was left at room temperature for 10 days, dried, immersed in 300g of glyoxal 10% aqueous solution at room temperature for 24 hours, filtered under reduced pressure with a Buchner funnel, left at room temperature for 24 hours, and then heated at 100°C for 1 hour. Heat treated. 50 g of this treated product was ground 5 times for 1 minute each using a household mixer (National MX-120) and the particle size was measured. The results are shown in Table 1 (the same applies to the following Examples and Comparative Examples). Example 2 The same procedure as in Example 1 was carried out except that a 5% glyoxal aqueous solution was used. Comparative Example 1 The same procedure as in Example 1 was carried out except that water was used instead of the glyoxal aqueous solution. Example 3 100 g of shredded newspaper was dried at 35 to 40°C for 1 hour, immersed in a 10% glyoxal aqueous solution at room temperature, 12 hours later filtered under reduced pressure using a Buchner funnel, left to stand at room temperature for 24 hours, and then heat treated at 100°C for 1 hour. 50g of this processed material
1 with a household mixer (Nanational MX-120)
The powder was crushed 5 times for 5 minutes and the particle size was measured. Comparative Example 2 The same procedure as in Example 3 was carried out except that water was used instead of the glyoxal aqueous solution. Example 4 Paper mill waste (compositional analysis value: reducing sugars 54.3
%, pentozan 12.9%, sulfuric acid insoluble ash 17.8%,
Sulfuric acid soluble ash 6.5%, aluminum 1.8%) 100
g was dried at 35-40°C for 4 hours, immersed in 300g of 6.8% glyoxal aqueous solution at room temperature for 12 hours, separated and left at room temperature for 12 hours, then heat-treated at 100°C for 1 hour. 120)
The powder was ground 5 times for 1 minute each and the particle size was measured. Comparative Example 3 The same procedure as in Example 4 was carried out except that the same amount of water was used instead of the glyoxal aqueous solution.

[Table] It is clear that according to the method of the present invention shown in Table 1, a good fine powder can be obtained regardless of the type of reactive polymer material. Examples 5 to 9 20 g of paper is immersed in 300 g of either an aqueous glyoxal solution or an aqueous solution containing glyoxal and a curing accelerator, left at room temperature for 24 hours, then shredded and heat-treated, and then chopped in a household mixer for 30 seconds each. It was crushed 5 times and the particle size was measured. The conditions and results are shown in Table 2 (the same applies to the following Examples and Comparative Examples). Comparative Example 4 The same procedure as in Example 5 was carried out except that the paper was immersed in water instead of the glyoxal aqueous solution. Comparative Example 5 Sulfamic acid instead of glyoxal aqueous solution
Example 5 except that the paper was immersed in a 0.2% aqueous solution.
The test was conducted in the same manner. In this case, coloring was observed in the crushed material.

[Table] According to Table 2, it is clear that even in the case of the method of the present invention, the crushing effect is greater when a curing accelerator is used in combination than when glyoxal is used alone.

Claims (1)

[Claims] 1. A polymeric material having a reactive functional group having two or more functional groups that react with the functional group General formula [Formula] (wherein A or B is H, carbon number 1 to 1, respectively) 12 alkyl or aralkyl having 7 to 12 carbon atoms), heat to cause a crosslinking reaction, and pulverize the crosslinked reaction product. 2 PH processing of polymeric materials with reactive functional groups
7 or less, the pulverization method according to claim 1. 3. The pulverization method according to claim 1, wherein the polymeric material having a reactive functional group is treated in the presence of a catalytic amount of a metal salt, ammonium salt or amine salt of a strong acid.