JPH03272830A - Long fiber reinforced thermoplastic resin composition and its manufacture - Google Patents

Abstract

PURPOSE:To manufacture a long fiber reinforced resin composition of good fabrication properties with little hairiness by impregnating a fiber bundle for reinforcing with a first molten thermoplastic material by means of a crosshead, coating its surface with a second molten thermoplastic material and shaping the same through a shaping die. CONSTITUTION:A continuous fiber bundle 1 is provided, and high melting point fiber or the like, for example, glass fiber, carbon fiber, metallic fiber, aromatic polyamide fiber or the like, can be used as the kind of the fiber for reinforcing. As the shape of the fiber bundle, a roving-shaped fiber bundle is preferred from the viewpoint of easy handling. The fiber bundle 1 for reinforcing is guided to a crosshead 10, impregnated with a first molten thermoplastic resin material fed from a feeding section 8 and shaped by a shaping die 3, and then the surface of the impregnated fiber bundle is coated with a second molten thermoplastic material fed from a feeding section 9 and the bundle is shaped by a shaping die 5. It is preferable to use the second thermoplastic resin at the ratio of 1 - 50 pts. wt. to 99 - 50 pts. wt. of the first thermoplastic resin, and the genera tion of hairiness is controlled to a large extent by said ratio.

Description

DETAILED DESCRIPTION OF THE INVENTION [1. Field of Application] The present invention relates to a process for producing long fibers (reinforced thermoplastic resin compositions).

[Prior art and its problems = In recent years, pultrusion has attracted attention as a method for producing thermoplastic resin compositions reinforced with long fibers. Among these, a method in which a continuous reinforcing fiber bundle is impregnated with a melt of a raw thermoplastic resin in one batch and then shaped into a desired shape through a shaping die is easy to operate. Furthermore, the fiber content can be easily controlled.

However, this method of impregnating and shaping a melted thermoplastic resin in a respirator has a major problem in that fluffing occurs on the surface of the resulting molded product. This is done before impregnating with resin. 1. Fiber opening by John 1.3-le etc., molten resin Q) impregnation. Due to the viscous resistance of the molten resin, and the viscous resistance of the molten resin, some of the fibers in the continuous fiber bundle may break and become impregnated with resin. Pass the continuous fiber bundle through a shaping die [2 to squeeze out excess resin? It is thought that when shaping from scratch, the excess resin that has been squeezed out flows in the opposite direction, causing the fibers to separate from the breaking point, which appears as fuzz.

Such fluff not only impairs the appearance of the fiber-reinforced resin, but also results in poor moldability when the resin is subjected to secondary cutting such as injection molding. For example, when molding using a fluffy plate I/foot, the fluidity of the pellets is poor, causing bridging in the hopper and making molding impossible, or the necessary amount of resin being eaten by the scraper J knee. However, the problem arises that a molded product having the desired shape or characteristics cannot be obtained without this. There is also the problem that the fibers in the fuzzy portion break and scatter, impairing the working environment.

In this way, the continuous reinforcing fiber bundle is pulled with a force of 70
Place the thermoplastic resin melt on the head: 'X 4
Long fiber reinforced thermoplastic resin composition 0> Manufacture? Leaving,
・Although the strength of the drop is good and the resulting reinforced structure has excellent properties,
, ), and an improvement has been desired5. ``Means for solving the problem; Plastic resin J) Long fiber reinforced thermoplastic resin composition impregnated with melt.

In order to solve these problems in the manufacturing method of products and obtain a long fiber-reinforced resin material with less fuzz and good molding processability, Sung carried out intensive studies, elucidated the mechanism by which fuzz occurs, and made improvements to it. I found a solution and arrived at the I-1 tree invention.

That is, the present invention continuously draws reinforcing fiber bundles,
In a method for producing a long fiber-reinforced thermoplastic resin composition in which a melt of a thermoplastic resin is impregnated in a cross-rad, a reinforcing fiber bundle is impregnated with a melt of a first thermoplastic resin in a cross-rad. After that, the surface (first
Thermoplastic +! A long fiber-reinforced thermoplastic resin composition that is coated with a melt of a second thermoplastic resin that is the same as or different from the I1 fat, and then shaped by a molding die. Manufacture H > 2, and '- (This method provides the desired long fiber reinforced thermoplastic resin composition.

In order to carry out the present invention, for example, it is advisable to use the method shown in FIG.
The present invention will now be explained in more detail with reference to FIG. Of course, the invention is not limited to only the illustrative apparatus and method herein.

In producing the long fiber-reinforced thermoplastic resin composition in the present invention, a continuous reinforcing fiber bundle 1 is supplied. There are no restrictions on the type of reinforcing fibers used; For example, glass fiber, carbon fiber, fully flexed fiber,
Any type of fiber (high melting point, high softening point) such as aromatic polyamide fiber can be used, and any form of continuous fiber such as pin, yarn, etc. can be used. In particular, it is preferable to use a low-pin shape at the C point because it is easy to handle. In the present invention, it is also possible to use two or more of the above-mentioned fibers in combination. In addition, these fibers have good adhesion with resin,
It may be treated with a known surface treatment agent. This reinforcing fiber bundle is then impregnated with a molten thermoplastic resin in a crosshead, and is preferably heated in advance so that the high-temperature reinforcing fiber bundle is brought into contact with the molten resin. It is also preferable to spread the fibers using a tension r1-ru or the like.

Next, the reinforcing fiber bundle is guided to the reinforcing fiber bundle D head, and first
3, the ratio of the first thermoplastic resin used for impregnation to the reinforcing wA Konto is determined by the desired final composition (!lli fiber content ratio) and Depending on the amount of second thermoplastic resin used in the next coating step -
7 will change, but - for boat fishing, reinforcing fiber bundles 10 to 85
The first thermoplastic resin cotton 110 is impregnated with 15% by weight based on the total amount.

Preferably about 21 to 80% by weight of reinforcing fibers, about 80 to 20% by weight, more preferably about 60 to about 40 to 75% by weight of reinforcing fibers. 25Φ9%.

If the ratio of the first thermoplastic resin to be impregnated into the reinforcing fiber bundle is in the middle, the content of the fiber bundle will not only increase in d content and ferri content, but also cause a secondary addition to this 4 history. ] 2 (For example, body /] Form 1) The physical properties of the finished product are also inferior 1: Preferably, <F; W) 0% trowel, the first for impregnating the fiber bundle. Examples of thermoplastic resins include polyesters such as polyethylene, polypropylene, polyethylene ester, polybutylene terephthalate, nylon 6, nylon 66, nylon 11, nylon 12, nylon Polyy'mide such as 612, polyacetanoyl, polycarbonate, polyurethane, polyphenylene oxide,
Any of the known S/Σ thermoplastic resins such as polyphenylene oxide, polysulfone, polyether ether, Horikome-tenol, 'fmide, and polyamide can be used.These resins can be used in two or more types. The first thermoplastic resin of the present invention may be used in combination with a mixture of When impregnated into fibers, it alone exhibits a sufficient reinforcing effect.
ti1'' Used for impregnation with resin) Ruri L] Shape of the throat, cross-\continuous fibers to the throat, S 1st
There are no particular restrictions on the method of introducing the thermoplastic resin, and any known method can be applied.

A particularly preferred crosshead, as shown in the example in FIG. By passing the fiber bundle through a crosshead 2 and impregnating it with the first thermoplastic resin while pulling the fiber bundle under tension, the fiber bundle that has arrived at f = 1 of the thermoplastic resin becomes f
The resin is squeezed by the f'+-shaped barrier, and the resin is promoted to the fiber bundle.

Now, in the production of a long fiber reinforced thermal 11J plastic resin composite using a conventionally known crosshead; A to impregnate thermoplastic resin, as described above, The processed continuous fiber bundle is directly passed through a shaping die, where the excess resin is squeezed out, and the bundle is shaped into a strand, tape, sheet, or special shape, etc. At 6, 20) when the die cap was pulled out, the shape-forming die was squeezed and the Puni resin was squeezed: Well, the drawing direction 5J- of the continuous fiber bundle was relatively opposite.
The shear stress generated by &1 in the J direction (this flow 17, this: this) causes a continuous fiber bundle (this action j1, fiber east and outside!) to break some of the fibers in the bud. One side of the die (J-Y-0), but some of the fibers are damaged.

7, 2, 1", sea urchin 17"7. +-: The delicate cutting point and this, - the fiber 0) opening, the magnetic or impregnating process, the soft fiber ζ) cutting; the analysis point is 2, the size is 5. ; [j, such as, the continuous fiber bundle is drawn, 9. tensioned by the flow of excess resin in the opposite direction j, 2 flow 4'' relative to lJ4, !jJ1 Y from Weito, lJ The surface of the reinforced resin composition taken off from the shaping die appears as fluff. Such fluff is a problem that cannot be avoided with conventional methods.However, in the present invention, in order to solve the problem of such fluff, the first thermoplastic resin is impregnated. surface of continuous fiber bundle (
1, the second thermoplastic resin is coated with the melted thermoplastic resin of the brush 2 and shaped with a shaping die]' The plastic resin is the first thermoplastic resin. 9)]~50
It is preferably used in a ratio of 21 to 50 parts by weight, and particularly in a ratio of 9 to 50 parts by weight.
7~70@Illusion in the weight part 3・-30 double hollow part" 3,
10th thermoplastic resin 2nd weight (if the ratio of 1st plastic resin is too low, 1 hair x 12 Q-) problem revised Tomoe 4
On the contrary, if the proportion of mo is too high (if it becomes too high, the composition of the citrus fruit after the secondary pressurization will be too low), and the fiber a degree will be locally reduced. The second thermoplastic phase (preferably, not because it occurs) is deferred to the melt and coated with the first thermoplastic resin, and the first thermoplastic resin 11ii is added to the continuous layer 1. It is not particularly necessary to shape the brim, but in order to make the coating with the second thermoplastic resin more effective, it is best to shape and keep it for boat fishing. In that case, too much resin must be squeezed out from the shaping die.
), it is best to narrow down the most bonding resin by using the shaping die after coating the second thermoplastic resin (6), and the cross-sectional area of each nozzle of the former shaping die is the same as that of the latter Each nozzle tI of the die
I-mj product 1.2~: 3 times the value is 1,
stomach. This 1. Therefore, the cause of the fiber breakage and the growing fuzz in this step C is eliminated. In addition, the coating process with the second thermoplastic resin melt is carried out separately from the first thermal impregnation process; However, as shown in Fig. 1G), the first thermoplastic resin is
... T111 soot, which is directly connected to the forming die provided for shaping the brim or one piece as desired.
Coating using brim ■] Functions as a reinforcing fiber bundle: Cool and solidify the first heat-impregnated 6J plastic resin.
Then, the fiber bundle is sent to the covering layer, and a second heated molten plastic resin is pressed into the upper part of the coating using an extruder or gear pump to cover the reinforcing fiber bundle. It is particularly preferred that the second thermoplastic resin used for the coating be any known thermoplastic resin such as those exemplified as the first thermoplastic resin used for the impregnation. Furthermore, the second thermoplastic resin may be the same as or different from the first thermoplastic resin.

Next: Reinforcing weave coated with second thermoplastic resin
The molten resin is drawn out using a 7-shaping die while squeezing the excess molten resin, and is shaped into a desired shape. At this time, the reinforcement i1i which passes through the shaping die is impregnated with the first thermoplastic resin, and the surface of the i1i is coated with the second thermoplastic resin. ), compensation, overload 6 t; 1 The direct effect on reinforcing fiber bundles due to the incorporation of fat is relaxed, and even when strong squeezing is performed, conventionally,
After impregnating with resin, immediately shape it with a shaping die! , :'at lt
It was. The occurrence of fluff (fuzz) is greatly suppressed.

The long fiber-reinforced resin composition obtained by this 6 cm, 18 cm, and 18 cm, was collected by using a 13I filter, etc. 3, and the collected resin tribe f! Although it is possible to transfer the material as it is to the molding process, etc., for boat fishing, it is better to cut it into a pellet shape and cut it into an appropriate length for injection molding, etc. preferable.

As described above, the present invention is characterized by a method for producing a long fiber-reinforced thermoplastic resin, and its composition,
For example, if the content of reinforcing fibers is 9,
Although there is no restriction, the effect of the present invention on lees is remarkable when the content of reinforcing fibers is large, e.g., 40-80 wt/h1%. Considering the various physical properties of reinforcement, the blending amount of #-1 Orishii and 1. Ic1-80 modification% (thread f1.7i in sight) is preferable. (2 Inoha 20 to 170'
h-Water% (in the composition). Also, Ki-nii jll! m
Accordingly, the resin composition obtained may contain, depending on the purpose and use, - General; each persimmon substance added to the thermoplastic resin;
For example, antioxidant, heat resistance, stabilizer, purple +1. Stabilizers such as line absorbers, antistatic agents, lubricants, EiJ plastic agents, # formulations, N flame agents, flame retardant aids, crystallization accelerators, colorants such as dyes and pigments, etc. are blended. It is also possible. These additives may be used in a pre-blended form: (i) the above-mentioned heat (i) which serves as a matrix;

〔Example〕

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited thereto.

Example 1 and Comparative Example 1-2 Using an apparatus having a configuration roughly as shown in FIG. Another '] (first heat i
'J Plastic resin supply section> 8 to 10) Melt of thermoplastic resin (5, polypropylene (Ml 15)
30°C), impregnated with -Te', and shaped with a shaping die 3 with a nozzle diameter of 5 mm, melted polypropylene (M+==1.4) using a second heated 6J plastic resin. l thing (230
t:) is supplied from another supply section 9 (second heat supply section for plastic resin) to coat the surface of the impregnated fiber bundle, and then shaped using a shaping die 5 with a nozzle diameter of 3 mm. It was taken as a strand and cut, and the glass fiber content was 140% by weight (
A pellet-like composition with a length of 12 mm was obtained.

The first thermoplastic resin used for impregnation (+, ++ 15 polyp L" pyrene) and the second thermoplastic resin used for coating cMI ・-1 □ 4 = f IJ pyrene ) is 90:10 (ffi!la).

On the other hand, for comparison, the forming die 3 and the second
heat of 111K] Plastic resin' 11g-1i y King culm 4
was removed, and using a device with a nozzle diameter of 3mrn connected to the 7th part of the device, the first heat = iJ! '!
! melt (
A pellet-like composition impregnated with only 230 °C in Comparative Example 1 and 2'lOt in Comparative Example 2 was prepared, and the preparation of Composition 1 of Example 1 and Comparative Examples 1 to 2 was carried out. Strand size, ′, 1, γ1. ) Observing the conditions and shape of the pellets obtained, injection molding test pieces using these pellet compositions, and evaluating them using the measurement method described in Section 1. ,y j,″.

The results are shown in Table 1.15.゛Show 4゛.

Tensile strength: Compliant with AST Shi+ 0638 Impact strength: A
In accordance with STM D-256, the impact strength of 2, notch and 1 T is measured (thickness of the test piece is 6.3 mm). Using a melt obtained by mixing pyrene (+, ++, 1.4) in the same proportion as in Example 1, pellets 7) were prepared and evaluated under the conditions of Comparative Examples 1 and 2. Comparative examples 1 and 2
There's not much of a difference.-1.

Example 2 and Comparative Examples 3 to 4 Using a melt (250°C) of Polybutylene L. Leftare
A pellet-shaped composition of Example 2 was prepared and evaluated in the same manner as in Example 1 except that a melt (250°C) of thermoplastic resin (MI=10) was used. The ratio of the second thermoplastic resin is 90:1.0 (weight ratio).

On the other hand, for comparison, polybutylene ethylene terephthalate) (+
, ++. are shown in Table 2.

〔Effect of the invention〕

As is clear from the above explanation and examples, in the method for producing a long fiber reinforced thermoplastic resin composition in which a reinforcing fiber bundle is continuously drawn and impregnated with a melt of thermoplastic resin in a crosshead, According to the method of the present invention, the fiber bundle is impregnated with a melt of the first thermoplastic resin, and then the surface thereof is coated with the melt of the second thermoplastic resin, and the fiber bundle is shaped through a shaping die. The fuzz problem that could not be avoided in conventional melt pultrusion molding using a crosshead has been significantly improved, and the surface is smooth and the shape is sharp.

Since a long fiber reinforced resin composition is obtained6, it is preferable when making this into a final product, and also when molding is performed using this, it has a major feature of good workability in the molding part. Furthermore, the long fiber reinforced resin composition produced by the method of the present invention also has the secondary effect of improving the problem of fiber loosening and scattering due to poor impregnation.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram, but does not show an example, of a method (and manufacturing apparatus) for producing a long fiber-reinforced thermoplastic resin composition using spuds, which is preferably applied to the present invention. 1... Reinforcing fiber bundle 2... First heat, plastic resin: Stagnation step 3...
・Shaping die 4...Second heat-resistant resin: Second coating step 5
. . . Shaping die 6 . . Take-up roll 7 . . . Paraqueizer 8 . . . First thermoplastic resin supply section 9 . . . Second thermo-71iJ plastic resin supply section 10 .
・Cross head

Claims (1)

[Scope of Claims] 1. A method for producing a long fiber-reinforced thermoplastic resin composition in which a continuous reinforcing fiber bundle is impregnated with a melt of thermoplastic resin in a crosshead while being drawn. After impregnating the melted material of the first thermoplastic resin, the surface thereof is further coated with a melted material of a second thermoplastic resin that is the same as or different from the first thermoplastic resin, and is shaped through a shaping die. A method for producing a long fiber-reinforced thermoplastic resin composition. 2. The crosshead impregnates the reinforcing fiber bundle with the melt of the first thermoplastic resin, and impregnates the surface of the reinforcing fiber bundle impregnated with the melt of the first thermoplastic resin with the second thermoplastic resin. It has a coating process for coating the melt and a shaping die for shaping it, and while drawing a continuous reinforcing fiber bundle through the crosshead, the first
The long fiber-reinforced thermoplastic resin composition according to claim 1, wherein the long fiber-reinforced thermoplastic resin composition is impregnated with a melt of a second thermoplastic resin, then coated with a melt of a second thermoplastic resin, and shaped through a shaping die. Production method. 3. The first thermoplastic resin and the second thermoplastic resin were heated to 99% or more.
It is used at a ratio of 50:1 to 50 (weight ratio) to impregnate and coat reinforcing fiber bundles, and 10 to 80% by weight in the composition.
The method for producing a long fiber reinforced thermoplastic resin composition according to claim 1 or 2, comprising reinforcing fibers. 4. A composition obtained by the method for producing a long fiber-reinforced thermoplastic resin composition according to any one of claims 1 to 3, wherein the composition comprises reinforcing fibers and a first fiber impregnated therein.
An inner layer made of a thermoplastic resin and an outer layer made of a second thermoplastic resin coated on the surface and containing no reinforcing fibers, and the reinforcing fibers are substantially continuous over the entire longitudinal length of the resin composition. A long fiber-reinforced thermoplastic resin composition characterized in that the long fibers are arranged in a substantially parallel state.