KR20040092074A - Polyester resin production having excellent reheating property - Google Patents

Abstract

PURPOSE: Provided is a polyester resin composition which facilitates reheating of polyester while maintaining the clearness of resin. CONSTITUTION: The polyester resin composition is prepared by admixing 4 to 40 ppm of a mixture(2:1) of Black iron oxide and Carbon black as an additive to a polyester resin obtained by mixing 65 wt% of terephthalic acid(TPA) and 31 wt% of ethylene glycol(EG) based on 100 wt% of the polyester resin in the mole ratio of 1:1.2, and adding to the mixture 400-700 ppm of antimonic triacetate(Sb(CH2COO)3·4H2O) as a polymerization catalyst, 100-200 ppm of triethyl phosphate as a heat stabilizer, 2.0-4.0 mol%/PTA of high purity isophthalic acid(IPA) as a block copolymerization modifier and 80-170 ppm of cobalt acetate(Co(CH2COO)2·4H2O) as a color improver. Particularly, the black iron oxide and carbon black have a spherical particle of about 10 to 2000 nm.

Description

Polyester resin composition having excellent reheating property

The present invention relates to a polyester resin composition having excellent reheating performance. More specifically, the present invention relates to a composite particle made by mixing black iron oxide and carbon black in a 2: 1 ratio, and mixing the composite particles in a content of 4 to 40 ppm. The present invention relates to a polyester resin composition which improves reheating performance by polymerizing a polyester resin.

Conventionally, 60-68 wt% of terephthalic acid and 28-32 wt% of ethylene glycol are mixed as a raw material of a polyester resin, 250-350 ppm of Sb2O3, 150-250 ppm of H3PO4, and 50-100 ppm of Cobalt Acetate are added as additives, and high purity is used as a raw material. It was prepared by adding 1.0-2.5 mole% / PTA of isophthalic acid, but it showed color L (resin of brightness by dividing the color of the resin by contrast) when a large amount of inorganic particles were added to improve reheating performance of polyester. The brighter the color, the higher the value of Color L.) and the worse the transparency of the resin.

In order to solve this problem, in the present invention, composite particles of black iron oxide and carbon black were used as additives to speed up the reheating of the polyester among various inorganic particles, and the size of the particles was also used to maintain transparency of the resin. 10 to 2000 nm spherical powder particles were used.

Heat lamps used in preform reheating for commercial production of beverage bottles are generally quartz lamps having a light emission spectrum of 500-1500 nm.

In order to speed up the reheating by increasing the endothermic performance of polyester with poor heat absorption in the range of 500 to 1400 nm, an additive that helps heat absorption in the range of 700 to 1200 nm can be added during the polymerization of polyester resins. Since color reheat additives have a negative effect on the color L of the resin, very small amounts should be used, and additives should be selected to increase the rate of reheating in small amounts.

Fe 3 O 4 + Carbon black composite was selected as the additive, and the additive was selected as a spherical powder with particle size in the range of 10-2000 nm and added during polyester polymerization.

As a result of the polymerization, the reheating rate was increased even with a small amount of less than 50ppm. When using 4 to 40ppm of composite powder particles, the color L of the resin decreased slightly, but the reheat time was reduced by at least 10% (see Table 2).

1 is a schematic diagram of a Richt performance evaluation equipment process of a polyester resin

<Brief description of symbols for the main parts of the drawings>

1: halogen lamp 2: pyrometer

3: preform 4: pyrometer sensor

5: Preform holder 6: Lamp stand

7: support box 8: diffuse reflection insulation table

The polyester resin used in the present invention is 65 wt% terephthalic acid (TPA) and ethylene glycol (EG) 32wt%, that is, TPA: EG in a mole ratio of 1: 1.2, and black iron oxide and carbon black as an additive 4 to 40 ppm by mixing 2: 1, 400 to 700 ppm of antimontriacetate (Sb (CH2COO) 3.4H2O) as a polymerization catalyst, 100 to 200 ppm of triethyl phosphate as a heat stabilizer, high purity as a block copolymer modifier Isophthalic acid (IPA) is prepared by adding 80 to 170 ppm of cobalt acetate (Co (CH2COO) 2.4H2O, Cobalt acetate) as 2.0 to 4.0 mole% / PTA, color improving agent.

In addition, in order to maintain the transparency of the resin, the additives of black iron oxide and carbon black particles were adjusted to about 10 to 2000 nm as spherical particles.

Referring to Figure 1 describes the performance evaluation equipment used in the experiment of the present invention.

The halogen lamp 1 supported by the lamp stand 6 is installed on one side of the diffuse reflection insulation table 8, and the support box 7 is installed on the other upper portion of the diffuse reflection insulation table 8.

The preform holder 5 is installed on the support box 7, and the preform holder 5 is provided with a pyrometer sensor 4 so that the pyrometer 2 and the pyrometer sensor 4 are electrically connected. Is connected.

First, all of the preforms 3 prepared in the preform processing step are kept at room temperature for 24 hours, and then set in the preform holder 5. Secondly, the pyrometer (2) and the pyrometer sensor (4) are connected, and the pyrometer sensor (4) is installed in the preform (3). Third, the halogen lamp 1 for heating the preform 3 is fixed at a position 40 cm away from the preform holder 5 and irradiated to the preform 3. Fourth, after heating, the temperature of the preform 3 is measured with a pyrometer (see Examples 1 to 7, Comparative Example 1).

Resin was prepared by varying the content of black iron oxide (Fe3O4) and carbon black composite particles during the polymerization of polyester, and preforms were prepared for each additive content using a bottle molding machine.

Black iron oxide (Fe3O4) and carbon black were added to the sample (Sample) and seven samples added by content were prepared to measure the RIV (Reheat Index Value).

The preform was placed in a holder for each sample, and heating was allowed to transmit for 15 seconds by emitting light at a temperature of 2000 ° C. (Max. 1100 nm wavelength) using a halogen lamp heater. The endothermic performance was recorded by measuring the temperature of the preform after permeation.

The temperature of the preform at room temperature was the initial temperature Ti and the temperature of the heating (Heating) was recorded as Tf. The temperature rise was recorded as ΔT (Tf-Ti) (shown in Table 2), and the average value (ΔTavg) was obtained after calculating ΔT for each of the four preforms in order to control the temperature change due to the micro-difference of the preform thickness. Calculated.

Here, RIV (Reheat Index Value) = (ΔTavg sample / ΔTavg Reference) was defined, and the reheat performance improvement (RI%) was calculated as RI (%) = ((RIVsample -RIVcontrol) / RIVcontrol) * 100. The measurement results for each sample and reference sample are shown in Table 1. (Reference refers to a polyester copolymer without using the Fe 3 O 4 + carbon black additive, and RIVcontrol means ΔTavg of Reference.)

Comparative Example 1 Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 additive Reference FC Addition amount (ppm) 0 4 8 12 16 20 30 40 RIV - 1.51% 3.77% 6.60% 10.18% 14.53% 23.90% 31.69% L * 84.71 84.34 83.62 82.50 81.12 79.20 75.10 71.80 △ L * 0.00 -0.37 -1.09 -2.21 -3.59 -5.51 -9.61 -12.91 RIV / △ L * - 4.08 3.45 2.98 2.83 2.63 2.49 2.45

* FC: Fe3O4 + Carbon black

Concentration (ppm) Ti (℃) Tf (℃) ΔT (℃) RIV (%) 0 25 78 53 4 25 78.8 53.8 1.51 8 25 80.0 55 3.77 12 25 81.5 56.5 6.60 16 25 83.4 58.4 10.18 20 25 85.7 60.7 14.53 30 25 90.7 65.7 23.90 40 25 94.8 69.8 31.69

As described above, the present invention adds Fe 3 O 4 + carbon black as an additive to the polyester resin to improve the endothermic performance of the polyester resin, thereby minimizing the heating time of the resin, and thus increasing the preform heating process speed. It has the effect of increasing the productivity and maintaining the transparency of the polyester resin.

Claims (2)

65 wt% of terephthalic acid (TPA) and 31 wt% of ethylene glycol (EG), that is, TPA: EG were mixed at a mole ratio of 1: 1.2 with respect to 100 wt% of polyester resin, and antimontriacetate (Sb (CH2COO) was used as a polymerization catalyst. 3 ~ 4H2O) 400 ~ 700ppm, triethyl phosphate as thermal stabilizer 100 ~ 200ppm, high purity isophthalic acid (IPA) 2.0 ~ 4.0 mole% / PTA as block copolymer modifier, cobalt acetate as color improver Polyester comprising the addition of 4 to 40 ppm by mixing black iron oxide and carbon black 2: 1 as an additive to a polyester resin prepared by adding 80 to 170 ppm of Co (CH2COO) 2 · 4H2O, Cobalt acetate) Resin composition. The polyester resin composition of claim 1, wherein the additives of black iron oxide and carbon black are spherical particles having a size of about 10 to 2000 nm.