TW201420634A - Poly(1,4-cyclohexylenedimethylene terephthalate) having enhanced crystallization rate - Google Patents

Abstract

A polycyclohexylenedimethylene terephthalate resin composition according to the present invention includes a polycyclohexylenedimethylene terephthalate resin, a glass fiber, and a high heat resistant polycyclohexylenedimethylene terephthalate resin. The polycyclohexylenedimethylene terephthalate resin composition according to the present invention has an effect of improving crystallization rate.

Description

Polyethylene terephthalate resin composition with improved crystallization rate

The present invention relates to a poly(cyclohexanedimethylene terephthalate) resin composition. More specifically, the present invention is directed to a polycyclohexanedimethylene resin composition having an improved crystallization rate.

Polyethylene terephthalate resin (hereinafter referred to as PCT resin) has been used in the manufacture of fibers, films and molded articles, and has excellent physical properties such as high abrasion resistance, durability and thermal stability. . The high crystallinity of the PCT resin is indispensable for ensuring sufficient hardness, strength and heat resistance at elevated temperatures. In order to ensure sufficient crystallinity, the PCT composition typically requires a mold temperature of 150 ° C or higher. High mold temperatures are only possible with advanced molding equipment, such as special heating units, such as oil bath heating units.

Therefore, in order to lower the required mold temperature, it has been proposed to use crystallization assist as a method of promoting crystallization of poly(alkylene terephthalate) at a lower temperature. The use of ester compounds as crystallization aids is described in U.S. Patent Nos. 4,223,125 and 4,223,113. Other types of crystallization aids include ketones, guanamines, and sulfonamides. However, these additives are volatile at elevated temperatures, resulting in a loss of volatility of the additives during the drying process, making the PCT composition difficult to dry after compounding.

Therefore, the composition of PCT needs to be moldable at a low temperature, maintain sufficient physical properties, and have an increased crystallization rate.

The invention provides a poly(cyclohexanedimethylene terephthalate) tree with improved crystallization rate Fat composition.

A poly(cyclohexanedimethylene terephthalate) resin composition according to one aspect of the present invention comprises: a cyclodextonate resin and a highly heat resistant poly(cyclohexanedimethylene terephthalate resin) Resin and glass fiber.

In the above, the content of the poly(cyclohexanedimethylene terephthalate resin) may be 60 to 95% by weight based on the total resin.

The glass fiber may be included in an amount of 20 to 60 parts by weight based on 100 parts by weight of the total resin, and the glass fiber may be in the form selected from the group consisting of filaments, threads, fibers, whiskers ( Group of whiskers).

In the above, the content of the highly heat-resistant polyethylene terephthalate resin may be 5 to 40% by weight based on the total resin.

Further, the highly heat-resistant polycyclohexanedimethylene resin can be produced by using cyclohexanedimethanol having a trans configuration of 80% by mole or more.

Further, the composition may further comprise a titanium compound, an oxidation stabilizer, and a lubricant.

According to another aspect of the present invention, there is provided a molded article prepared from the composition.

The poly(cyclohexanedimethylene terephthalate) resin composition according to the present invention has an effect of increasing the crystallization rate.

The invention can be variously modified and can have various embodiments. Specific embodiments of the invention will be described in detail in the preferred embodiments. However, it can be understood that this issue The invention is not limited to the specific embodiments, and the invention is intended to be included within the spirit and scope of the invention. In the description of the present invention, if the detailed description disclosed in the related prior art is considered to be unclear, it is not presented.

The present invention provides a composition comprising a polycyclohexanedimethylene terephthalate resin, glass fibers, and a highly heat resistant poly(cyclohexanedimethylene terephthalate) resin.

As a method of increasing the crystallization rate of the polymer resin, an organic nucleating agent composed of a low molecular weight organic material, and an inorganic nucleating agent such as an inorganic filler may be added. Further, the melt crystallization rate of the resin can be improved by adding a predetermined amount of a polymer resin having a high melting point to the resin. In the present invention, a polybutylene terephthalate resin having high heat resistance is used.

Hereinafter, the polybutylene terephthalate resin composition according to an embodiment of the present invention will be described in more detail.

According to an embodiment of the present invention, there is provided a composition comprising a resin composed of a polyethylene terephthalate resin and a high heat resistant poly(cyclohexanedimethylene terephthalate resin), and a glass fiber.

In the above, the poly(cyclohexanedimethylene terephthalate resin) is preferably a terephthalic acid-1,4 composed of monomer units of 1,4-cyclohexanedimethanol and terephthalic acid. - Cyclohexanedimethyl ester resin because this resin exhibits good crystallinity when molded at a low temperature. These resins can be prepared by using well-known general techniques.

Meanwhile, the content of the poly(cyclohexanedimethylene terephthalate resin) may be 60 to 95% by weight based on the total resin.

The poly(cyclohexanedimethylene terephthalate) composition according to the present invention may comprise 20 to 60 parts by weight of glass fibers, based on 100 parts by weight of the total resin. Further, the glass fibers may be in the form of glass filaments, threads, fibers, whiskers or the like, and may have a length of preferably 3 to 5 mm. In order to reduce the distortion of the linear portion, the polyethylene terephthalate resin may be reinforced by a mixture of a plate type filler such as mica and glass fibers.

Meanwhile, in the case of a poly(cyclohexanedimethylene terephthalate) resin, two isomeric forms, trans and cis, exist in cyclohexanedimethanol (CHDM) as a raw material. In general, CHDM contains about 70 mole % of the trans configuration, and the content of the trans isomer in the general CHDM can be changed via the isomerization reaction in the presence of a catalyst. Here, when the content of the trans is increased, the melting point and heat resistance of the polyethylene terephthalate resin prepared using CHDM are improved.

Therefore, in the present invention, in the polymerization of a poly(cyclohexanedimethylene terephthalate) resin having a high heat-resistant polycyclobutylene terephthalate resin having a high melting point and heat resistance, in the CHDM The trans ratio is increased, which can be applied to a general polycyclohexanedimethylene resin, thereby increasing the crystallization rate.

Adding 80 mol% or more of trans-CHDM, terephthalic acid and a catalyst to carry out an esterification reaction and a polycondensation reaction, thereby obtaining a high heat-resistant poly(cyclohexanedimethylene terephthalate) having a high molecular weight Resin. For example, the highly heat resistant polycyclohexanedimethylene resin thus obtained may have an intrinsic viscosity of 0.65 dl/g and a melting temperature of 305 °C.

That is, such a highly heat-resistant poly(cyclohexanedimethylene terephthalate resin) can be produced by using cyclohexanedimethanol containing 80% by mole or more of trans.

In the above, the content of the highly heat-resistant polyethylene terephthalate resin may be 5 to 40% by weight based on the total resin.

The highly heat-resistant polybutylene terephthalate resin thus obtained can be uniformly mixed with the substrate PCT (Base PCT) via a kneading process. Injecting a highly heat-resistant poly(cyclohexanedimethylene terephthalate) resin, a twin-screw extruder may be used, which may have a suitable length to diameter ratio (L/D) of about 30 to 50.

In addition, such compositions may in turn include additives such as titanium compounds, an oxidation stabilizer, and a lubricant to improve the processability of the resin.

According to another aspect of the present invention, there is provided a molding prepared from the composition Product.

detailed description

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail. However, the examples are for illustrative purposes only and the scope of the invention is not limited by these examples.

Example 1

60 parts by weight of glass fiber and 0.2 parts by weight of oxidative stabilizer (AO-60) and lubricant (high-lubrication (Hi-Lube)) in a twin-screw extruder (Φ: 40 mm, L/D = 44) ), based on 100 parts by weight of the resin consisting of 60% by weight of PCT resin (melting point: 285 ° C, melt crystallization temperature: 245 ° C) and 40% by weight of high heat resistance PCT resin (Tm: 305 ° C, Tmc: 270 ° C) The resin is uniformly kneading and extruded to obtain pellets. The pellets thus prepared were injected with an average of an injection temperature of 295 ° C and an injection pressure of 1500 kg force / cm 2 using an injector. The injection was carried out in a tensile test die of 150 ° CASTM, and the time (ejection cooling time) of the injected product which was stably separated from the mold after solidification by solidification was measured.

In addition, based on the fact that increasing the melting crystallization temperature causes the crystallization rate to become faster, The melt crystallization temperature of the pellets was measured, and the crystallization rate was examined in the following manner. That is, to measure the melting crystallization temperature, the PCT was completely melted at 320 ° C using a differential scanning calorimeter (DSC), and the sample was cooled at a cooling rate of 20 ° C / min, and the maximum crystallization peak was crystallized through the sample ( Crystallization Max. Peak) to measure the melting crystallization temperature.

Example 2

Twin-screw extruder (Φ: 40 mm, L/D = 44) 40 parts by weight of glass fiber and 0.2 parts by weight of oxidative stabilizer (AO-60) and lubricant (high-lubrication (Hi-Lube)) 100 parts by weight of the resin consisting of 80% by weight of PCT resin (melting point: 285 ° C, melt crystallization temperature: 245 ° C) and 20% by weight of high heat resistance PCT resin (Tm: 305 ° C, Tmc: 270 ° C) Resin.

Thereafter, pellets were prepared in the same manner as in Example 1, and the injection cooling time and the melt crystallization temperature were measured.

Example 3

Twin-screw extruder (Φ: 40 mm, L/D = 44) 40 parts by weight of glass fiber and 0.2 parts by weight of oxidative stabilizer (AO-60) and lubricant (high-lubrication (Hi-Lube)) , based on 100 parts by weight of the resin consisting of 90% by weight of PCT resin (melting point: 285 ° C, melt crystallization temperature: 245 ° C) and 10% by weight of high heat resistance PCT resin (Tm: 305 ° C, Tmc: 270 ° C) Resin.

Thereafter, pellets were prepared in the same manner as in Example 1, and the injection cooling time and the melt crystallization temperature were measured.

Example 4

A twin-screw extruder (Φ: 40 mm, L/D = 44) added 20 parts by weight of glass fibers and 0.2 parts by weight of an oxidation stabilizer (AO-60) and a lubricant (high-lubrication (Hi-Lube)) 100 parts by weight of the resin consisting of 95% by weight of PCT resin (melting point: 285 ° C, melt crystallization temperature: 245 ° C) and 5% by weight of high heat resistance PCT resin (Tm: 305 ° C, Tmc: 270 ° C) Resin.

Thereafter, pellets were prepared in the same manner as in Example 1, and the injection cooling time and the melt crystallization temperature were measured.

Comparative example 1

A twin-screw extruder (Φ: 40 mm, L/D = 44) added 60 parts by weight of glass fibers and 0.2 parts by weight of an oxidation stabilizer (AO-60) and a lubricant (high-lubrication (Hi-Lube)) Based on 100 parts by weight of PCT resin (melting point: 285 ° C, melt crystallization temperature: 245 ° C).

Thereafter, the pellets were prepared in the same manner as in Example 1 and cooled when the injection was cooled. The temperature between the melt and the crystallization temperature was measured.

The experimental results of the examples and comparative examples are summarized in Table 1 below.

As shown in Table 1, it can be seen that the poly(cyclohexanedimethylene terephthalate) resin composition according to the present invention exhibits a short ejection cooling time and a high melting crystallization temperature, thereby having an improved crystallization rate.

The above are only the preferred embodiments of the present invention, and all changes and modifications made to the scope of the present invention should be within the scope of the present invention.

Claims (8)

A composition comprising a resin composed of a polyethylene terephthalate resin and a high heat resistant poly(cyclohexanedimethylene terephthalate) resin, and glass fibers. The composition of claim 1, wherein the poly(cyclohexanedimethylene terephthalate resin) is present in an amount of from 60 to 95% by weight based on the total of the resin. The composition of claim 1, wherein the glass fiber is present in an amount of from 20 to 60 parts by weight based on 100 parts by total of the total resin. The composition of claim 1 wherein the glass fibers are selected from the group consisting of filaments, threads, fibers, and whiskers. The composition of claim 1, wherein the high heat resistant poly(cyclohexanedimethylene terephthalate) resin is present in an amount of from 5 to 40% by weight based on the total of the resin. The composition of claim 1, wherein the highly heat-resistant polycycloethylene terephthalate resin is prepared by using cyclohexanedimethanol having 80% by mole or more of trans. The composition of claim 1 further comprising a titanium compound, an oxidation stabilizer, and a lubricant. A molded article obtained by the composition of any one of claims 1 to 7.