Polyester fiber for airbag and preparation method thereof

[0106]Hereinafter, preferable examples and comparative examples are presented for understanding the present invention. However, the following examples are only for illustrating the present invention and the present invention is not limited to or by them.

[0107]According to the processing conditions shown in the following Table 1, esterification reactions of terephthalic acid and ethylene glycol were carried out at a temperature range of 250-280° C. for 4 hours with a mole ratio (ethylene glycol / terephthalic acid) of 1.3. After the esterification reactions, polycondensation reactions of the prepared oligomers were carried out in a temperature range of 280-290° C. for 3 hours 30 minutes so as to prepare polymers.

[0108]After the polycondensation reactions, additional ethylene glycol was introduced with a content of 1% and 3% with regard to the total content of the glycol initially introduced, respectively, in the condition of normal pressure. The additional reactions were carried out at a high vacuum of 0.5 Torr for 1 minute or more. Particularly, the additional reactions were carried out so that the intrinsic viscosity (IV) of the melt-polymerized polyester polymers (chips) prepared through the additional reactions became about 0.5-0.8

[0146]Raw fabrics for an airbag was woven from the polyester fibers prepared according to Examples 1-5 by using a Rapier Loom, and were prepared into fabrics for an airbag through the scouring and tentering processes. Then, a polyvinylchloride (PVC) resin was coated on the fabrics with a knife-over-roll coating method to obtain PVC coated fabrics.

[0147]At this time, the weaving density of warps and wefts, the weaving type, and the amount of coating resin of the fabrics were as disclosed in the following Table 5, and the other conditions for Preparation Examples 1-5 followed conventional conditions for preparing a polyester fabric for an airbag.

[0148]

TABLE 5PreparationPreparationPreparationPreparationPreparationExample 1Example 2Example 3Example 4Example 5Weaving densityWarp5353534949(warp × weft)Weft5353534949Weaving typePlainPlainPlainPlainPlainAmount of coating resin2525253030(g / m2)

[0149]The properties of the polyester fabrics for an airbag prepared by using the polyester fibers of