JP2003261739A - Resin modifier composed of styrene-butadiene copolymer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an easy and inexpensive means for improving various characteristics of a resin such as PET to facilitate the secondary and tertiary processing of the resin and improve the productivity and recyclability of the resin. <P>SOLUTION: The resin modifier is composed mainly of a styrene-butadiene copolymer. A modified resin is produced by blending a resin with the modifier. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a resin modifier containing a styrene-butadiene copolymer as a main component, and a method for producing a modified resin by blending (compounding) the modifier.

[0002]

2. Description of the Related Art Polyethylene terephthalate (PET)
Resin has excellent environmental safety (low calorific value of incineration combustion, easy combustion, no harmful gas is generated during permeable combustion, etc.), transparency, oxygen and moisture barrier property, strength and thermal stability. On the other hand, because of its poor mechanical properties and molding properties, it has hitherto been used only in limited applications such as fibers, films, sheets and beverage bottles.

Also, in recent years, with the rapid expansion of the utilization of PET bottles and the like, a recovery (recycling) system is being established. The recycled raw material of PET bottles recovered in this way has remarkably physical properties. It is in a situation where it cannot be reused because it is decreasing. As a specific problem, new factory equipment (auxiliary equipment) is required to improve such deteriorated physical properties. Using such a means, compared with manufacturing raw material (virgin raw material) That is, the cost of the recycled raw material becomes high, and the recycled PET raw material thus obtained is not suitable for injection molding and profile extrusion molding (damage occurs during molding).

[0004]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to improve various characteristics of a resin such as PET, thereby facilitating secondary and tertiary processing thereof, and further improving productivity and recyclability. It is to provide a simple and low-cost means that can be done.

[0005]

Means for Solving the Problems The present inventor has blended a styrene-butadiene copolymer with these resins to maintain various excellent mechanical properties, The inventors have found that the molding characteristics can be improved and completed the present invention. That is, the present invention relates to a resin modifier containing a styrene-butadiene copolymer as a main component. Furthermore, the present invention relates to a method for producing a modified resin, which comprises blending the resin with the modifier of the present invention.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The styrene-butadiene copolymer (SBC), which is the main component of the resin modifier of the present invention, is characterized by its structural characteristics such as random copolymer, alternating copolymer and block copolymer. It can be roughly classified into a coalesced product and a graft copolymer. The SBC used in the present invention is not particularly limited in terms of structure, but is preferably a styrene-butadiene block copolymer, and generally has a molecular weight of 110,000 to 200,000 (expressed as "weight average molecular weight", hereinafter the same), Preferably 130,000-19
In many cases. Also, there is no particular limitation on the mixing ratio of styrene to butadiene in the styrene-butadiene copolymer,
It is preferably 85:15 to 65:35 (weight ratio).
Various types of styrene-butadiene copolymers satisfying such conditions are commercially available, and those skilled in the art can easily select an appropriate resin according to the resin to be modified and its physical properties. You can get it.

The resin modifier of the present invention includes, in addition to the above-mentioned styrene-butadiene copolymer, other resins such as polyolefin resins such as polyethylene and polypropylene and thermoplastic saturated polyester resins such as PET, and Any substance known to those skilled in the art can be appropriately contained as the property-imparting material and the additive. The mixing ratio of such other components is not particularly limited, but other resins such as a polyolefin resin can be contained in the same ratio as the styrene-butadiene copolymer.

The method of using the resin modifier of the present invention is not particularly limited. For example, various properties of the resin can be improved by simply blending the resin modifier with the resin. The type of resin is not particularly limited, and examples thereof include thermoplastic saturated polyester resins represented by polyethylene terephthalate (PET) resins (those containing dicarboxylic acid and glycol as main raw materials) and olefin resins. PET resins also include recycled materials recovered from various forms of products. It is also possible to use a material obtained by appropriately adding such a recycling material to a virgin material. Further, the PET resin includes a resin containing ethylene glycol and a diol other than terephthalic acid and a dicarboxylic acid component, for example, a resin containing a cyclohexyne dimethanol and a polyester binding portion composed of isophthalic acid or terephthalic acid. An example of such a resin is PET-G series sold by Eastman Chemical Company. Representative examples of olefin resins include polyethylene (PET) resins (including PE of various densities such as LDPE, MDPE, and HDPE), and polypropylene (PP) resins (homo, block, and random, all compositions). (Including those).

By blending such a resin with an appropriate amount of the resin modifier of the present invention, various properties can be improved and a modified resin can be produced. The mixing ratio of the resin and the modifier when blending is not particularly limited, and can be appropriately selected by those skilled in the art according to the kind of the resin, the purpose of modification, the kind of the final product, and the application. Generally, 1 to 50%, preferably 5 to 30% by weight of the total blend of the modifier is blended with the resin. The blending method itself can be performed using any means and conditions known to those skilled in the art. For example, in the case of blending (compounding) a PET resin and a resin modifier, a range of 240 to 260 ° C. is usually suitable, and in particular, the recycle PET resin is well dried before blending, and the resin and Tumbling the resin modifier is preferred.

By blending the resin modifier of the present invention, for example, mechanical properties such as tensile strength, tensile elongation, elastic modulus, bending strength, and impact resistance, and dimensional stability and melting point reduction, etc. The characteristics such as moldability and workability are improved by. Other properties that are modified by blending the resin modifier of the present invention are, for example, anisotropy, heat sealability, heat packability, embossability, printability, and adhesiveness.

As described above, since the modified resin produced by blending with the resin modifier of the present invention has excellent properties, for example, gardening such as flower pots, planters, and buckets. Cleaning items such as household items, dust boxes, mini buckets, and storage cases, organizing cases, stationery items such as fancy boxes, various food wrapping films such as fresh food, various food trays, automobiles, steel plates, protective films for painting It can be used for a wide range of applications such as laminate films of aluminum and steel cans, calendar films, various vacuum forming materials, wallpaper films, building materials films and building materials (stair handrails, anti-slip, etc.).

Such a final product can be manufactured using various conditions and means known to those skilled in the art.
For example, when forming a film or sheet, the drying temperature is usually 180 ° C or lower, the hopper set temperature is 170 to 180 ° C,
The cylinder set temperature is 240 to 260 ° C, the T die set temperature is 240 to 260 ° C, and the cooling temperature can be set lower. At the time of injection molding, usually, the hopper set temperature is around 180 ° C, the cylinder set temperature is 240 to 260 ° C,
Nozzle setting temperature 240-260 ° C, mold temperature 20-40
It can be ℃.

[0013]

The present invention will be described in detail below with reference to examples, but the technical scope of the present invention is not limited to these examples. In addition, "%" shows "weight%" in the following implementation.

Example 1PET resin with styrene-butadiene block copolymer
Modification of fat Virgin PET resin with styrene-butadiene block
Resin modifier consisting of polymer SBC (molecular weight: 150,000)
Blend each amount and then simultaneously biaxially stretch (3.5 x 3.5)
To prepare a film sample. For them, the following characteristics
Got the value. The film sample was prepared at a drying temperature of 180.
℃, hopper set temperature 180 ℃, cylinder set temperature 1
80 ℃, T-die set temperature 260 ℃, Cooling temperature 30 ℃ / R
And

[0015]

[Table 1]

From the results shown in Table 1, it is understood that the tensile property is improved by blending the styrene-butadiene block copolymer with the virgin PET resin.

Example 2Recycle with styrene-butadiene block copolymer
Modification of PET resin Recycle PET resin with styrene-butadiene block
Copolymer SBC ((Molecular weight: 150,000) 5 wt% and Polio
Made from 5% by weight of refin ("NF1702" manufactured by Chisso Corporation)
The resin modifier is blended, and then the test piece is prepared.
It was They were tested according to JIS standards and the following characteristic values
Got In addition, the sample is made by injection type (screw type),
Hopper set temperature 180 ℃, cylinder set temperature 240
℃, nozzle set temperature 240 ℃, mold cooling temperature 35 ℃
It was

[0018]

[Table 2]

From the results in Table 2, it can be seen that the recycled PET resin was blended with the resin modifier of the present invention to improve the tensile strength and impact resistance.

Example 3 The resin modifier of the present invention was prepared by blending the styrene-butadiene block copolymer SBC and each resin in various proportions. It was injection molded and various properties of the obtained resin modification of the present invention were measured. For injection molding, a screw type device (Kawaguchi Tekko Co., Ltd.) was used, and the hopper temperature setting was 180 ° C.
(Table 3 and Table 4) or 170 ° C (Table 5), cylinder set temperature: 260 ° C (Table 3), 230 ° C (Table 4) or 22
0 ° C (Table 5), nozzle set temperature: 260 ° C (Table 3), 2
20 ° C (Table 4) or 190 to 200 ° C (Table 5), mold temperature: 45 ° C (Table 3), 40 ° C (Table 4) or 35 to 40 ° C
(Table 5). Further, each physical property value in each table was measured by a standard method defined in ASTM standard. For example, flexural strength and flexural modulus (D790), tensile strength (D636), tensile elongation (D638), notched Izod impact strength (D256).

[0021]

[Table 3]

[0022]

[Table 4]

[0023]

[Table 5]

From Table 3, a kind of PET resin (G-
It can be seen that various characteristics of PET), in particular, tensile strength and impact resistance (notched Izod impact strength) are improved. From Table 4, it can be seen that various properties of PP, which is a type of polyolefin resin, in particular, special impact resistance (notched Izod impact strength) and tensile elongation (at break) were significantly improved. From Table 5, HD which is a kind of polyolefin resin
It can be seen that various characteristics of PE, in particular, bending strength and bending elastic modulus were improved.

[0025]

EFFECTS OF THE INVENTION By using a styrene-butadiene copolymer as a resin modifier, various mechanical properties and molding properties can be easily and inexpensively maintained while retaining various properties originally possessed by the resin. It has been found that the modified resin can be improved and can be used for various purposes. In particular,
By modifying a recycle PET resin or the like with the resin modifier of the present invention, a high quality recycle raw material can be provided at a low cost, and thus the recyclability thereof is improved.

Claims (10)

[Claims] 1. A resin modifier containing a styrene-butadiene copolymer as a main component. 2. The resin modifier according to claim 1, wherein the styrene-butadiene copolymer is a styrene-butadiene block copolymer. 3. The resin modifier according to claim 1 or 2, wherein the styrene-butadiene block copolymer has a molecular weight of 130,000 to 190,000. 4. The compounding ratio of styrene to butadiene is 85:
The resin modifier according to any one of claims 1 to 3, wherein the resin modifier is 15 to 65:35. 5. The resin modifier according to any one of claims 1 to 4, further comprising an olefin resin. 6. The resin modifier according to any one of claims 1 to 5, wherein the resin is a thermoplastic saturated polyester resin. 7. The resin modifier according to claim 6, wherein the resin is a polyethylene terephthalate resin. 8. The resin modifier according to claim 7, wherein the resin is a recovered polyethylene terephthalate resin. 9. A method for producing a modified resin, which comprises blending a resin with the resin modifier according to any one of claims 1 to 5. 10. The method for producing a modified resin according to claim 9, wherein the resin modifier is blended in an amount of 5 to 30% by weight of the total blend.