JPS6149823A - Extrusion molding method of thermosetting resin - Google Patents

Abstract

PURPOSE:To manufacture continuously a molded article whose appearance is favorable, by performing screw extrusion of a thermosetting resin composite material whose extrusion flow is within a range of 1-42g. CONSTITUTION:Extrusion molding is performed continuously by a screw type extruder by making use of a thermosetting resin composite material which has been controlled so that a rate of efflux in extrusion flow teat (JISK6911, mold charge 55g, temperature 140 deg.C, pressure 150g/cm<2>) is made into 1-42g. Control of an extrusion flow is performed by controlling either combination of kinds and quantities of resin, a curing agent, a filler and the other additive or, in case of the same composition, heating and mixing processes of a roll and kneader. An extrusion-molded article whose thermal rigidity and mechanical strength are high and surface smoothness is excellent can be manufactured continuously.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is applicable to the field of architecture, electricity, electronics, etc. [Prior Art] Methods for molding thermosetting resins include compression molding, transfer molding, Injection molding method and extrusion.

Shaping methods are known, and molding materials suitable for each molding method are used.

Among these methods for molding thermosetting resins, two extrusion methods have been developed: a plunger extrusion method and a screw extrusion method.

[Problem that the invention seeks to solve]

Plunger extrusion is used to produce long extruded products with simple shapes such as round bars and pipes. However, in the plunger extrusion molding apparatus, the extrusion pressure in the mold section is high and intermittent extrusion is used, so it is difficult to obtain uniform molded products and the productivity is low.

Under these circumstances, a molding method using a so-called screw type extrusion molding device has been developed. This is a molding device that guides thermosetting resin molding material kneaded and melted in an extruder into a mold through an adapter and shapes it into a final shape. However, with conventional thermosetting resin molding materials, the molding material gradually hardens inside the extruder and the extrusion pressure increases, eventually making extrusion impossible and making long-term operation extremely difficult.

[Means for solving problems]

As a result of repeated studies in the field of construction, electricity, electronic minutes, etc., the present inventors found that in extrusion molding of thermosetting resins, the amount of other additives to the thermosetting resin material is large. We found that controlling the overall fluidity is especially important for thermosetting resin composite materials that have flow rates in the range of 1 to 4,2'7 in the extrusion flow test (JTSK6911). We found a way to solve this problem and arrived at the present invention.

That is, in the present invention, the flow rate in the extrusion type flow test (J I SK, 6911) of thermosetting resin composite material is 1 to 4.
A thermosetting resin extrusion molding method characterized by continuous extrusion molding after adjusting the temperature to
50 kg and 7 cm).

In the present invention, the extrusion type flow of the thermosetting resin composite material is
〜42!7, consider combinations of types and amounts of resins, curing agents, fillers, lubricants, flame retardants, colorants, molding agents, plasticizers, and other additives. Of course, it is also possible to do this by adjusting the heating and mixing processes of rolls, kneaders, co-kneaders, etc. when manufacturing molding materials when the compositions are the same. By changing the temperature of the rolls and the kneading time, it is possible to easily produce a molding material having an extrusion type flow within the above range.

Thermosetting resins used in the present invention include thermosetting resins such as phenol resins, melamine resins, urea resins, epoxy resins, unsaturated polyester resins, allyl resins, silicone resins, xylene resins, aniline resins, and crosslinking agents. Total added polyethylene, polypropylene, polystyrene,
Examples include thermoplastic fats such as polyvinyl chloride. In particular, phenolic resin is suitable for extrusion molding using the extrusion molding machine incorporating the screw of the present invention.

The phenolic resin used in this case is a novolak resin obtained by reacting phenols such as phenol, cresol, xylenol, and resorcinol with formaldehydes such as aqueous formaldehyde, paraformaldehyde, and trioxane using an acidic catalyst, or an alkaline catalyst. Any of the resol resins obtained by reacting with can be used.

A curing agent such as hexamine or paraformaldehyde is added to the phenol resin as necessary, and further, 8 to 20 parts by weight is usually added to 100 parts by weight of the phenol resin. If the amount of the curing agent is less than 8 parts by weight, the resulting molded product will have poor thermal rigidity, while if it exceeds 20 parts by weight, a large amount of ammonia will be generated during molding, causing blisters on the surface of the molded product. There is a tendency not to.

Further, commonly known fillers, lubricants, excipients, flame retardants and colorants are added, kneaded and pulverized to obtain a phenolic resin molding material for extrusion molding. All kneading and pulverization can be carried out by known methods. That is, a hot roll or co-kneader can be used for kneading, and a speed mill, power mill, etc. can be used for grinding.

Fillers include, but are not limited to, carbon black, colloidal silica, glass powder, magnesia, basic magnesium silicate, magnesium carbonate, magnesium hydroxide, various silicates, alumina powder, calcium carbonate, diatomaceous earth. Inorganic substances such as powder, kaolin, celite, acid clay, ± non-m fibers such as lamic fiber, asbestos, rock wool, glass fiber, carbon fiber, etc.
,・Paper valve, cotton 1. It can be used in the form of fibers such as organic fibers such as linters, polyimide fibers, vinylon fibers, aromatic polyamide fibers, and aromatic polyester fibers, or in the form of woven or nonwoven fabrics. -As a lubricant,
Although not particularly limited, higher fatty acids such as stearic acid and palmitic acid, alkaline earth metal salts (calcium salts, magnesium salts) of higher fatty acids, montan acid wax, and amides of higher and higher fatty acids can be used.

The lubricant may be added by mixing it with a resin or the like, or it may be added after the molding material is produced depending on the situation.

As the coloring agent, carbon black, spirit black, molybdenum red, phthalocyanine blue, phthalocyanine green, and Hansa yellow can be used.

As plasticizers, furfural, alkylphenol,
tricresyl phosphate, polyethylene glycol,
Commonly used compounds such as dibutyl phthalate-1-1P-)luenesulfonamide are effective.

Flame retardants are not particularly limited, but include antimony oxide, chlorinated paraffin, perchloropentacyclodecane, tris (β-chloroethyl) phosphate, tris (dichloropropyl) phosphate, tris (2,
3-dibromopropyl) phosphate, tris(bromo, chloropropyl)bosphate, triphenyl phosphate, decabromodiphenyl ether, hexabromodiphenyl ether, red phosphorus, tin oxide, tin hydroxide,
Molybdenum oxide, ammonium molybdate, zirconium oxide, zirconium hydroxide, barium metaborate,
Examples include zinc borate.

The amount of filler used is novolak type phenolic resin material 10
The amount is usually 100 to 400 parts by weight, preferably 150 to 250 parts by weight. The lubricant is usually used in an amount of 0.5 to 2.0 parts by weight per 100 parts by weight of the novolac type phenolic resin. The amount of plasticizer used is usually 0.2 to 2 parts by weight per 100 parts by weight of novolac type phenolic resin.
．． It is 0 parts by weight. Furthermore, the amount of flame retardant used is usually in the range of 10 to 20 parts by weight per 100 parts by weight of the novolac type phenolic resin.

In the extrusion molding method using a built-in screw in the present invention, there are various limitations depending on the compression ratio of the screw, the gap between the screw and the barrel, in other words, the wall thickness of the molded product, and the extrusion speed, depending on the curing characteristics of the molding material used. receive. The larger or smaller the compression ratio of the screw, the larger or smaller the back pressure applying function. If the back pressure is too large, excessive kneading will occur, resulting in excessive heat generation and hardening of the material, which is undesirable. On the other hand, if the back pressure is too low, compression filling and kneading of the material will become insufficient, which is likewise undesirable, and appropriate back pressure and appropriate kneading are required. That is, in order to achieve stable extrusion and a good product, appropriate compression ratio of the screw and curing characteristics of the molding material are required.

The extrusion molding machine in which the thermosetting resin extrusion molding material of the present invention is suitably used usually has a screw compression ratio of 1.0 to 5.0.
Preferably 1.2-4.01, more preferably 1.5-3
It is in the range of 0.

[Effect]

The feature of the present invention is that the appearance of the molded product is good by using a thermosetting resin composite material with an extrusion flow rate of 1 to 42 when continuously extruded using a screw.
In addition, it is preferable to use a continuously stable product with a weight in the range of 1 to 42 g, preferably 1 to 38 g, particularly preferably 1 to 35 g.
! 7 is good. When the extrusion flow rate is less than 1, the surface of the molded product becomes severely rough and cavities occur. Also, 42g
In the above cases, the molded product swells and deforms, and stable continuous molding over a long period of time is not possible, and in some cases, it hardens in the extrusion barrel, making molding impossible, and the molded product has poor surface smoothness. Moreover, the molded product has high thermal rigidity and excellent mechanical strength, and can be continuously and stably molded into extruded tubes, extruded plates, extruded rods, etc.

The present invention will be explained below with reference to Examples and Test Examples.

〔Example〕

Example 1 Novolac resin (manufactured by Mitsui Toatsu Chemical Co., Ltd. +9000, softening point 95°C), hexamine, glass fiber (chopped strand), clay, asbestos, spirit black,
Stearic acid, magnesium stearate, silane coupling agent (Nippon Unicar (decoy, product name A=1100,
(hereinafter abbreviated as A, -1100) were mixed at the blending ratios shown in Table 1.

The resulting mixture was roll-kneaded for 8 minutes under the temperature conditions of a front roll temperature of 95 to 100°C and a rear roll temperature of 55 to 60°C.

The kneaded material was pulverized and sized using a power mill (screen 4 m/m). The extrusion flow rate of the resulting granular molding material was 2.0 g.

Example 2 A molding material was produced under the same conditions as in Example 1, except that the kneading time was changed to 4 minutes.

The extrusion flow of this was 30.02.

Example 3 Novolac resin (manufactured by Ohdon Toatsu Kagaku Co., Ltd. +2000, softening point 96°C), hexamine, glass fiber (chopped strand), spirit black, stearic acid, magnesium stearate in the blending ratio shown in Table 1 mixed with.

The resulting mixture was roll-kneaded for 10 minutes at a temperature of 100 to 110°C with the front roll and 55 to 60°C with the back roll, and then
Grind with a power mill (using a 4m/m screen),
The grains were sorted. The extrusion flow rate of the molding material obtained was 41.5
! ;l! Met.

Comparative Example 1 A molding material was produced under the same conditions as in Example 1 except that the kneading time was changed to 9 minutes. The extrusion flow of this is 0
．． It was 5g.

Comparative Example 2 A molding material was produced in the same manner as in Example 3, except that the kneading time was 8 minutes. The extrusion type flow of this is 4
It was 3.5g.

Example 4 Bisphenol A type epoxy resin (manufactured by Tobu Kasei Co., Ltd.) YD
-011, epoxy equivalent 475), ortho-cresol novola, ri-type epoxy resin (manufactured by Tobu Kasei Co., Ltd.) YDON-
220L, epoxy equivalent: 225), 4,4'-diaminodiphenylmethane, silica powder, montan wax, and carbon black were sufficiently mixed in a kneader at the blending ratios shown in Table 1.

The obtained mixture was pulverized and sized using a power mill to obtain a molding material. The extrusion flow of this was 34.09.

Example 5 Melamine formaldehyde resin liquid (formaldehyde/
Melamine ratio 2:1, solid content 90%) and cut dissolving pulp (α-cellulose) were placed in a mixer, and
Mixed for 30 minutes at 0°C. After drying this, zinc stearate and hexamine were added, and the mixture was ground using a ball mill to obtain a molding material. The extrusion flow of this is 30,0
It was ri.

The blending ratios and extrusion flows of Examples 1 to 5 and Comparative Examples 1 to 2 are summarized in Table 1 below.

Extrusion molding test example A land length of 300 at the tip of an ordinary screw extruder having a diameter of 40 m/m, L/D = 18, and a compression ratio of 1.6.
Is it possible to install a m/m die with an outer diameter of 40m1? ? Z-1 inner diameter 36
A cylindrical pipe of m/m was molded.

The extruder conditions are from below the hopper: 0~4D-11 room temperature 5~12D-
1-60°C 13~18D-1-100°C Head section-----1--110°C Adapter part----- 110℃ land part 0~100m/m--120℃100
-200m/m--150°0 200-300m1m--160°C, and extrusion was carried out under the conditions of screw rotation speed 18 rpm.

The test results are shown in Table 2.

Procedure Amendment (December 1982)
21st of the month

Claims (1)

[Claims] (1) Extrusion flow test for thermosetting resin composite materials (JIS
A thermosetting resin extrusion molding method characterized by continuous extrusion molding after adjusting the flow rate in K6911) to 1 to 42 g (however, the measurement conditions for the extrusion flow test are a charging amount of 55 g, a temperature of 140°C, The pressure shall be 150Kg/cm^2).