BIODEGRADABLE RESIN COMPOSITION AND FISHING NET PRODUCED FROM SAME

Abstract

The present invention relates to a biodegradable resin having outstanding colouring properties, and provides a resin composition which does not give rise to problems such as reduced strength due to colouration. The composition of the present invention, suggests that a PBSAT resin is used as a biodegradable resin, and colouration is performed with same. Also, at this time, the colourant can be mixed in the form of masterbatch. In the present invention, the resin composition is used in the production of various products, in particular monofilament yarn produced via spinning and a fishing net manufactured from same is provided. Fishing nets such as the above are advantageous in that such fishing nets can be realized in various colours in accordance with customer requirements and satisfy the required strength and, after use, degrade naturally in seawater and so do not give rise to problems like environmental pollution.

Claims

1. A biodegradable resin composition comprising a colorant that is included at 0.005 to 0.015 parts by weight with respect to 100 parts by weight of a polybutylene succinate-co-adipate-co-terephthalate) (PBSAT) resin.

2. The biodegradable resin composition according to claim 1, wherein the colorant is one or more selected from the group consisting of phthalocyanine green, carbon black, phthalocyanine blue, an iron oxide, and triphenylmethane.

3. The biodegradable resin composition according to claim 1, the colorant is provided in the form of a masterbatch having a structure that includes a colorant and a biodegradable resin which covers the colorant.

4. The biodegradable resin composition according to claim 1, the PBSAT resin has a molecular weight (Mw) in a range of 100,000 to 200,000.

5. The biodegradable resin composition according to claim 1, the PBSAT resin includes a residue of succinic acid:adipic acid:phthalic acid in a range of 70 to 90:5 to 15:5 to 15 mol %.

6. Monofilament yarn manufactured from the resin composition of claim 1.

7. A fishing net manufactured using a part or all of the monofilament yarn of claim 6.

Description

EXAMPLE 1

(1) Preparation of PBSAT Resin

[0034] 63.1 kg of dimethyl terephthalate (DMT) (325.0 mol) and 702 kg of 1,4-butanediol (7800.0 mol) were added as base materials in a reactor (5 t) equipped with a condenser, a nitrogen inlet pipe, and a stirrer, and 325.0 g of trimethyl phosphate and 130 g of triphenyl phosphate as a thermal stabilizer and 4550.0 g of titanium(IV) butoxide as a catalyst were further added in the reactor, and then a transesterification reaction was performed under conditions of temperature of 200 C. for 1 hour to release methanol (CH.sub.3OH) in an amount corresponding to a theoretical yield. When methanol was released in an amount of 22.1 L corresponding to a theoretical yield, the temperature was raised to 220 C., 47.5 kg of adipic acid (325.0 mol) and 690 kg of succinic acid (5850.0 mol) were further added, and then an esterification reaction was performed for 1 hour to form oligomers. In this case, water was released in an amount corresponding to a theoretical yield. When water was released in an amount corresponding to approximately 95% of a theoretical yield (2220 L), 325 g of titanium(IV) butoxide as a subsequent catalyst and 2600 g of cobalt acetate as a coloring agent were added and the temperature was raised to 240 C. Then, a polycondensation reaction was performed under conditions of a high-degree vacuum of 1 Torr or less for 2 hours to remove an unreacted base material (unreacted monomer), an oligomer having a low molecular weight, and byproduct water. As a result, a PBSAT resin having a molecular weight (Mw) of 100,000 was obtained.

(2) Preparation of Masterbatch

[0035] 1.5 g of phthalocyanine green as a colorant was added to 100 g of the PBSAT resin having a molecular weight (Mw) of 100,000, and the two materials were mixed in a melt extruder (TEM 35B twin-screw extruder) set at 180 C. Strands thus obtained were cooled in water and then cut to obtain a masterbatch.

(3) Preparation of Monofilament Yarn

[0036] 25 kg of the PBSAT resin prepared in the method (1) and the masterbatch for coloration in an amount prepared in the method (2) were mixed and then spun at a temperature of 230 C. In this case, a total drawing ratio was adjusted by adjusting a primary drawing ratio and a secondary drawing ratio to obtain monofilament yarn having a diameter of 0.285 mm (No. 3).

EXAMPLE 2

[0037] Monofilament yarn having a diameter of 0.165 mm (No. 1) was obtained in the same manner as in Example 1, except that 3.0 g of carbon black was used as a colorant instead of phthalocyanine green upon preparation of a masterbatch.

EXAMPLE 3

[0038] Monofilament yarn having a diameter of 0.405 mm (No. 6) was obtained in the same manner as in Example 1, except that 2.5 g of phthalocyanine blue was used as a colorant instead of phthalocyanine green upon preparation of a masterbatch.

EXAMPLE 4

[0039] Monofilament yarn having a diameter of 0.37 mm (No. 5) was obtained in the same manner as in Example 1, except that 1.5 g of an iron oxide was used as a colorant instead of phthalocyanine green upon preparation of a masterbatch.

EXAMPLE 5

[0040] Monofilament yarn having a diameter of 0.47 mm (No. 8) was obtained in the same manner as in Example 1, except that 2.0 g of triphenylmethane was used as a colorant instead of phthalocyanine green upon preparation of a masterbatch.

COMPARATIVE EXAMPLE 1

[0041] Monofilament yarn having a diameter of 0.285 mm (No. 3) was obtained in the same manner as in Example 1, except that a PBS resin (4560C commercially available from S-Enpol Co. Ltd) was used instead of a PBSAT resin upon preparation of monofilament yarn.

COMPARATIVE EXAMPLE 2

[0042] Monofilament yarn having a diameter of 0.165 mm (No. 1) was obtained in the same manner as in Example 2, except that a PBS resin (4560C commercially available from S-Enpol Co. Ltd) was used instead of a PBSAT resin upon preparation of monofilament yarn.

Evaluation

[0043] For the monofilament yarn according to Examples 1 to 5 and Comparative Examples 1 and 2, strengths were measured up to 1/1,000 g every 0.1 seconds using a constant speed extension-type tensiometer (Instron 3365, USA) by a KS K 0412 (2005) method. The results and drawing ratios upon spinning are shown in the following Table 1.

TABLE-US-00001 TABLE 1 Reference Measured Diameter Drawing strength strength No. ratio (kgf) (kgf) Example 1 3 7.5 3.0 3.1 Example 2 1 8.0 0.7 1.2 Example 3 6 7.0 5.8 6.1 Example 4 5 7.2 4.85 5.2 Example 5 8 6.8 7.85 7.9 Comparative 3 7.0 3.0 2.3 Example 1 Comparative 1 7.2 0.7 0.4 Example 2

[0044] Values exceeding reference strength are obtained in Examples 1 to 5, whereas monofilament yarn of the comparative examples exhibits a value lower than reference strength. That is, the resin composition according to the present invention has improved strength even after coloration, compared to an existing biodegradable resin, and may be used to manufacture a fishing net because values exceeding strength required for monofilament yarn of each diameter number are obtained.