Thermoplastic resin composition and article produced therefrom

Abstract

A thermoplastic resin composition of the present invention comprises: about 100 parts by weight of a polycyclohexylenedimethylene terephthalate resin having a crystallization temperature (Tc) of about 140 to about 170 °C for 10-15 mg of a sample, as measured using a differential scanning calorimeter (DSC) at a heating rate of 10 °C / min and a cooling rate of -5 °C / min; and about 35 to about 110 parts by weight of a polycarbonate resin. The thermoplastic resin composition has low oxygen permeability and has excellent chemical resistance, excellent high-temperature stability, excellent transparency, and an excellent balance of these properties.

Description

Thermoplastic resin composition and molded article manufactured therefrom

[0001] The present invention relates to a thermoplastic resin composition and a molded article manufactured therefrom. More specifically, the present invention relates to a thermoplastic resin composition having low oxygen permeability and excellent chemical resistance, high-temperature stability, transparency, and a balance of these physical properties, and a molded article manufactured therefrom.

[0002]

[0003] Polycarbonate resin is an engineering plastic that offers excellent impact strength, heat resistance, dimensional stability, weather resistance, flame retardancy, and electrical properties. Due to its transparency, it is primarily used in materials requiring physical durability and transparency. However, polycarbonate resin is susceptible to attack by water molecules and salts, making it vulnerable to alkalis and hydrolysis. Consequently, it exhibits high oxygen permeability and poor chemical resistance, which limits its application in medical materials.

[0004] Accordingly, a method has been proposed to mix polycyclohexylene dimethylene terephthalate (PCT) resin, which has excellent low oxygen permeability and chemical resistance, with polycarbonate resin; however, there is a problem in that PCT resin is difficult to apply to medical materials requiring transparency because there is a concern that transparency may deteriorate at high temperatures.

[0005] Therefore, there is a need to develop thermoplastic resin compositions that have low oxygen permeability and excellent chemical resistance, high-temperature stability, transparency, and a balance of these physical properties.

[0006] The background technology of the present invention is disclosed in Korean registered patent No. 10-0709878, etc.

[0007]

[0008] The objective of the present invention is to provide a thermoplastic resin composition having low oxygen permeability and excellent chemical resistance, high-temperature stability, transparency, and a balance of these physical properties.

[0009] Another objective of the present invention is to provide a molded article formed from the thermoplastic resin composition.

[0010] The above and other objectives of the present invention can all be achieved by the present invention described below.

[0011]

[0012] 1. One aspect of the present invention relates to a thermoplastic resin composition. The thermoplastic resin composition comprises about 100 parts by weight of a polycyclohexylenedimethylene terephthalate resin, wherein the crystallization temperature (Tc) of a 10 to 15 mg sample, measured using a differential scanning calorimeter (DSC) under conditions of a heating rate of 10°C / min and a cooling rate of -5°C / min, is about 140 to about 170°C; and about 35 to about 110 parts by weight of a polycarbonate resin.

[0013] 2. In the above 1 embodiment, the polycyclohexylene dimethylene terephthalate resin may have a melting temperature (Tm) of about 230 to about 290°C when measured by differential scanning calorimetry (DSC) under a heating rate of 10°C / min.

[0014] 3. In the above 1 or 2 embodiments, the polycyclohexylene dimethylene terephthalate resin may have a glass transition temperature (Tg) of about 80 to about 100°C when measured by differential scanning calorimetry (DSC) under a heating rate of 10°C / min.

[0015] 4. In the above 1 to 3 embodiments, the polycarbonate resin may have a weight-average molecular weight (Mw) measured by gel permeation chromatography (GPC) of about 20,000 to about 50,000 g / mol.

[0016] 5. In the above embodiments 1 to 4, the thermoplastic resin composition has an oxygen permeability of about 5 to about 25 cm for a 10 mm × 10 mm × 1 mm specimen measured according to ASTM D3895. 3 / (m 2It can be 24hr atm.

[0017] 6. In the above 1 to 5 embodiments, when 1 ml of MCT oil is applied to a 3.2 mm thick Type I tensile specimen made according to ASTM D638 standards and left in a 1% strain curvature jig, the time for cracks to occur on the surface of the specimen may be about 60 minutes or more.

[0018] 7. In the above 1 to 6 embodiments, the thermoplastic resin composition may have a haze of about 10% or less when the specimen is placed in a 120°C oven for 24 hours after the specimen has a thickness of 2 mm.

[0019] 8. In the above 1 to 6 embodiments, the thermoplastic resin composition may have a light transmittance of about 80% or more as measured according to ASTM D1003 after leaving a 2 mm thick specimen in a 120°C oven for 24 hours.

[0020] 9. Another aspect of the present invention relates to a molded article. The molded article is characterized by being formed from a thermoplastic resin composition according to any one of 1 to 8.

[0021] 10. In the above 9 embodiments, the molded article may be a transparent medical material.

[0022]

[0023] The present invention has the effect of providing a thermoplastic resin composition having low oxygen permeability and excellent chemical resistance, high temperature stability, transparency, and a balance of physical properties, and a molded article formed therefrom.

[0024]

[0025] The present invention will be described in detail below.

[0026] The thermoplastic resin composition according to the present invention comprises (A) polycyclohexylene dimethylene terephthalate resin; and (B) polycarbonate resin.

[0027] In this specification, "a to b" indicating a numerical range is defined as "≥a and ≤b".

[0028]

[0029] (A) Polycyclohexylene dimethylene terephthalate resin

[0030] The polycyclohexylene dimethylene terephthalate resin of the present invention can be applied together with polycarbonate resins, etc., to improve the chemical resistance, high temperature stability, transparency, and balance of physical properties of the thermoplastic resin composition, and to lower oxygen permeability. In this case, a polycyclohexylene dimethylene terephthalate (PCT) resin having a crystallization temperature (Tc) of about 140 to about 170°C can be used.

[0031] In a specific example, the crystallization temperature (Tc) of a 10 to 15 mg sample of the polycyclohexylene dimethylene terephthalate resin, measured using a differential scanning calorimeter (DSC) under conditions of a heating rate of 10°C / min and a cooling rate of -5°C / min, may be about 140 to about 170°C, for example, about 150 to about 160°C. If the crystallization temperature (Tc) of the polycyclohexylene dimethylene terephthalate resin is less than about 140°C, there is a risk that the high-temperature stability, transparency, etc. of the thermoplastic resin composition will be reduced, and if it exceeds about 170°C, there is a risk that the oxygen permeability of the thermoplastic resin composition will increase and chemical resistance, etc. will be reduced.

[0032] In a specific example, the polycyclohexylene dimethylene terephthalate resin may have a melting temperature (Tm) of about 230 to about 290°C, for example, about 240 to about 280°C, measured by differential scanning calorimetry (DSC) under a heating rate of 20°C / min. Within this range, the moldability of the thermoplastic resin composition may be excellent.

[0033] In a specific example, the polycyclohexylene dimethylene terephthalate resin may have a glass transition temperature (Tg) of about 80 to about 100°C, for example, about 85 to about 95°C, measured by differential scanning calorimetry (DSC) under a heating rate of 10°C / min. Within this range, the oxygen permeability of the thermoplastic resin composition may be low, and the chemical resistance, high temperature stability, transparency, etc., may be excellent.

[0034] In a specific example, the polycyclohexylene dimethylene terephthalate resin of the present invention may have an intrinsic viscosity [η] measured according to ASTM D2857 of about 0.5 to about 1.5 dl / g, for example, about 0.7 to about 1.3 dl / g. Within the above range, the mechanical properties of the thermoplastic resin composition may be excellent.

[0035]

[0036] (B) Polycarbonate resin

[0037] A polycarbonate resin according to one embodiment of the present invention can be applied together with the polycyclohexylene dimethylene terephthalate resin, etc., to improve the chemical resistance, high temperature stability, transparency, and balance of physical properties of the thermoplastic resin composition, and to lower oxygen permeability. A polycarbonate resin used in a conventional thermoplastic resin composition can be used. For example, an aromatic polycarbonate resin prepared by reacting diphenols (aromatic diol compounds) with precursors such as phosgene, halogen formate, and carbonate diester can be used.

[0038] In a specific example, the above diphenols may be exemplified as 4,4'-biphenol, 2,2-bis(4-hydroxyphenyl)propane, 2,4-bis(4-hydroxyphenyl)-2-methylbutane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 2,2-bis(3-chloro-4-hydroxyphenyl)propane, 2,2-bis(3,5-dichloro-4-hydroxyphenyl)propane, 2,2-bis(3-methyl-4-hydroxyphenyl)propane, 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane, etc., but are not limited thereto. For example, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(3,5-dichloro-4-hydroxyphenyl)propane, 2,2-bis(3-methyl-4-hydroxyphenyl)propane, 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane, or 1,1-bis(4-hydroxyphenyl)cyclohexane may be used, and specifically, 2,2-bis(4-hydroxyphenyl)propane called bisphenol-A may be used.

[0039] In a specific example, the polycarbonate resin may be used having branched chains, and for example, a branched polycarbonate resin may be used by adding about 0.05 to about 2 mol% of a trivalent or higher polyfunctional compound, specifically a compound having a trivalent or higher phenolic group, to the total amount of diphenols used in polymerization.

[0040] In a specific example, the polycarbonate resin may be used in the form of a homopolycarbonate resin, a copolycarbonate resin, or a blend thereof. Additionally, the polycarbonate resin may be partially or entirely replaced with an aromatic polyester-carbonate resin obtained by polymerizing in the presence of an ester precursor, such as a difunctional carboxylic acid.

[0041] In a specific example, the polycarbonate resin may have a weight-average molecular weight (Mw) measured by gel permeation chromatography (GPC) of about 20,000 to about 50,000 g / mol, for example, about 25,000 to about 40,000 g / mol. Within this range, the impact resistance, fluidity (processability), etc. of the thermoplastic resin composition may be excellent.

[0042] In a specific example, the polycarbonate resin may be included in an amount of about 35 to about 110 parts by weight, for example, about 40 to about 100 parts by weight, with respect to about 100 parts by weight of the polycyclohexylenedimethylene terephthalate resin. If the content of the polycarbonate resin is less than about 35 parts by weight with respect to about 100 parts by weight of the polycyclohexylenedimethylene terephthalate resin, there is a risk that the high-temperature stability, transparency, etc. of the thermoplastic resin composition will be reduced, and if it exceeds about 110 parts by weight, there is a risk that the oxygen permeability of the thermoplastic resin composition will increase and the chemical resistance, etc. will be reduced.

[0043]

[0044] A thermoplastic resin composition according to one embodiment of the present invention may further include additives included in conventional thermoplastic resin compositions. Examples of such additives include, but are not limited to, impact modifiers, flame retardants, antioxidants, anti-dropping agents, lubricants, release agents, nucleating agents, antistatic agents, stabilizers, pigments, dyes, and mixtures thereof. When using such additives, the content thereof may be about 0.001 to about 40 parts by weight, for example, about 0.1 to about 10 parts by weight, per about 100 parts by weight of the polycyclohexylenedimethylene terephthalate resin.

[0045]

[0046] A thermoplastic resin composition according to one embodiment of the present invention may be in the form of pellets produced by mixing the above components and melt-extruding them using a conventional twin-screw extruder at about 240 to about 300°C, for example, about 260 to about 290°C.

[0047] In a specific example, the thermoplastic resin composition has an oxygen permeability of about 5 to about 25 cm for a 10 mm × 10 mm × 1 mm specimen measured according to ASTM D3895. 3 / (m 2 ·24hr·atm), for example, about 10 to about 20 cm 3 / (m 2 It can be 24hr atm.

[0048] In a specific example, when 1 ml of MCT (medium chain triglycerides) oil is applied to a 3.2 mm thick Type I tensile specimen made according to ASTM D638 standards and left in a 1% strain curvature jig, the time for cracks to occur on the surface of the specimen may be about 60 minutes or more, for example, about 5 days or more.

[0049] In a specific example, the thermoplastic resin composition may have a haze of about 10% or less, for example, about 1 to about 5%, measured according to ASTM D1003 after leaving a 2 mm thick specimen in a 120°C oven for 24 hours.

[0050] In a specific example, the thermoplastic resin composition may have a light transmittance of about 80% or more, for example, about 85 to about 95%, measured according to ASTM D1003 after leaving a 2 mm thick specimen in a 120°C oven for 24 hours.

[0051]

[0052] The molded article according to the present invention is formed from the thermoplastic resin composition. The thermoplastic resin composition may be manufactured in the form of pellets, and the manufactured pellets may be produced into various molded articles (products) through various molding methods such as injection molding, extrusion molding, vacuum molding, and casting molding. Such molding methods are well known to those skilled in the art to which the present invention belongs. Since the molded article has low oxygen permeability and excellent chemical resistance, high-temperature stability, transparency, and a balance of these physical properties, it is useful as a transparent medical material, etc.

[0053]

[0054] The present invention is to be explained more specifically through the following examples, but these examples are for illustrative purposes only and should not be interpreted as limiting the invention.

[0055]

[0056] Examples

[0057] The specifications of each component used in the examples and comparative examples below are as follows.

[0058] (A) Polycyclohexylene dimethylene terephthalate resin

[0059] (A1) Polycyclohexylene dimethylene terephthalate (PCT) resin with a crystallization temperature (Tc) of about 155°C (melting temperature (Tm): about 260°C, glass transition temperature (Tg): about 85°C, intrinsic viscosity [η]: about 1.3 dl / g) was used.

[0060] (A2) Polycyclohexylene dimethylene terephthalate (PCT) resin with a crystallization temperature (Tc) of about 150°C (melting temperature (Tm): about 270°C, glass transition temperature (Tg): about 85°C, intrinsic viscosity [η]: about 1.3 dl / g) was used.

[0061] (A3) Polycyclohexylene dimethylene terephthalate (PCT) resin with a crystallization temperature (Tc) of about 160°C (melting temperature (Tm): about 260°C, glass transition temperature (Tg): about 90°C, intrinsic viscosity [η]: about 1.3 dl / g) was used.

[0062] (A4) Polycyclohexylene dimethylene terephthalate (PCT) resin with a crystallization temperature (Tc) of about 130°C (melting temperature (Tm): about 290°C, glass transition temperature (Tg): about 80°C, intrinsic viscosity [η]: about 1.3 dl / g) was used.

[0063] (A5) Polycyclohexylene dimethylene terephthalate (PCT) resin with a crystallization temperature (Tc) of about 173°C (melting temperature (Tm): about 270°C, glass transition temperature (Tg): about 90°C, intrinsic viscosity [η]: about 1.3 dl / g) was used.

[0064] (B) Polycarbonate resin

[0065] Bisphenol-A-based polycarbonate resin (PC, manufacturer: Lotte Chemical, weight-average molecular weight: approximately 28,000 g / mol) was used.

[0066]

[0067] Examples 1 to 5 and Comparative Examples 1 to 7

[0068] After adding each of the above components in the amounts listed in Tables 1 and 2 below, pellets were prepared by extrusion at approximately 270°C. A twin-screw extruder with L / D=44 and a diameter of 45 mm was used for extrusion. The prepared pellets were dried at approximately 80°C for at least 4 hours, and then injection molded in a 6 oz injection molding machine (molding temperature: approximately 270°C, mold temperature: approximately 120°C) to produce specimens. The physical properties of the prepared specimens were evaluated by the following method, and the results are shown in Tables 1 and 2 below.

[0069]

[0070] Methods for measuring physical properties

[0071] (1) Oxygen permeability (unit: cm 3 / (m 2 Oxygen permeability was measured for a specimen of 10 mm × 10 mm × 1 mm size according to ASTM D3895.

[0072] (2) Chemical resistance evaluation: 1 ml of MCT oil (medium chain triglycerides oil (coconut 100%)), product name: Pure C8 MCT oil) was applied to a 3.2 mm thick Type I tensile specimen made according to ASTM D638 standards, and then left in a 1% strain curvature jig. After that, the surface of the tensile specimen was observed for 5 days to see if any cracks occurred, and when cracks occurred, the time to crack occurrence was measured.

[0073] (3) Haze and light transmittance (unit: %): After leaving a 2 mm thick specimen in a 120°C oven for 24 hours, the haze and light transmittance (total light transmittance) of the specimen were measured using a Nippon Denshoku Haze meter NDH 2000 in accordance with ASTM D1003.

[0074]

[0075] Example 1 2345 (A1) (parts by weight) 100 100 100 -- (A2) (parts by weight) --- 100 -- (A3) (parts by weight) ---- 100 (A4) (parts by weight) ----- (A5) (parts by weight) ----- (B) (parts by weight) 42.9 66.7 100 66.7 66.7 Oxygen Permeability 12 15 17 13 19 Crack Occurrence None None None None None None Haze 3.8 92.9 1.9 3.0 1.5 Light Transmittance 86.5 87.5 87.7 87.0 87.8

[0076]

[0077] Comparative Example 1 234567 (A1) (parts by weight) 100 100 100 1000 -- (A2) (parts by weight) ------- (A3) (parts by weight) ------- (A4) (parts by weight) ----- 100 - (A5) (parts by weight) ------ 100 (B) (parts by weight) 0 17.6 33.3 150 100 66.7 66.7 Oxygen Permeability 8 10 10 40 80 11 40 Crack Occurrence No Crack No Crack No Crack Occurrence (32 min) Occurrence (20 min) No Crack Occurrence (45 min) Haze 9 0.6 60.2 20.4 1.5 1.2 25.3 1.2 Light Transmittance 49.0 76 3.9 79.7 38 8.0 88.5 76.5 88.5

[0078]

[0079] From the above results, it can be seen that the thermoplastic resin composition of the present invention has low oxygen permeability and excellent chemical resistance (prevention of cracking), high temperature stability, transparency (haze and light transmittance), and a balance of these physical properties.

[0080] On the other hand, in Comparative Example 1, which did not use polycarbonate resin, it was found that high temperature stability and transparency were reduced; in Comparative Examples 2 and 3, which used a small amount of polycarbonate resin, it was found that high temperature stability and transparency were reduced; in Comparative Example 4, which used an excessive amount of polycarbonate resin, it was found that oxygen permeability was high and chemical resistance was reduced; and in Comparative Example 5, which did not use polycyclohexylene dimethylene terephthalate resin, it was found that oxygen permeability was high and chemical resistance was reduced.

[0081] In addition, in Comparative Example 6, which uses a polycyclohexylenedimethylene terephthalate resin (A4) with a crystallization temperature (Tc) below the range of the present invention instead of the polycyclohexylenedimethylene terephthalate resin of the present invention, it can be seen that high temperature stability, transparency, etc. are reduced, and in Comparative Example 7, which uses a polycyclohexylenedimethylene terephthalate resin (A5) with a crystallization temperature (Tc) exceeding the range of the present invention, it can be seen that oxygen permeability is high and chemical resistance, etc. are reduced.

[0082]

[0083] The present invention has been described above with reference to embodiments. Those skilled in the art will understand that the present invention may be embodied in modified forms without departing from the essential characteristics of the invention. Therefore, the disclosed embodiments should be considered in an illustrative rather than a restrictive sense. The scope of the invention is defined by the claims, not by the foregoing description, and all variations within the scope of equivalents should be interpreted as being included in the invention.

Claims

1. About 100 parts by weight of a polycyclohexylenedimethylene terephthalate resin having a crystallization temperature (Tc) of about 140 to about 170°C of a 10 to 15 mg sample measured using a differential scanning calorimeter (DSC) under conditions of a heating rate of 10°C / min and a cooling rate of -5°C / min; and A thermoplastic resin composition characterized by comprising about 35 to about 110 parts by weight of polycarbonate resin.

2. A thermoplastic resin composition according to claim 1, characterized in that the polycyclohexylene dimethylene terephthalate resin has a melting temperature (Tm) of about 230 to about 290°C as measured by differential scanning calorimetry (DSC) under a heating rate of 20°C / min.

3. A thermoplastic resin composition according to claim 1 or 2, wherein the polycyclohexylene dimethylene terephthalate resin has a glass transition temperature (Tg) of about 80 to about 100°C as measured by differential scanning calorimetry (DSC) under a heating rate of 10°C / min.

4. A thermoplastic resin composition according to any one of claims 1 to 3, wherein the polycarbonate resin has a weight-average molecular weight (Mw) of about 20,000 to about 50,000 g / mol as measured by gel permeation chromatography (GPC).

5. In any one of claims 1 to 4, the thermoplastic resin composition has an oxygen permeability of about 5 to about 25 cm for a 10 mm × 10 mm × 1 mm specimen measured according to ASTM D3895. 3 / (m 2 A thermoplastic resin composition characterized by being 24hr atm.

6. A thermoplastic resin composition according to any one of claims 1 to 5, characterized in that, when 1 ml of MCT oil is applied to a 3.2 mm thick Type I tensile specimen manufactured according to ASTM D638 standards and left in a 1% strain curvature jig, the time at which cracks occur on the specimen surface is approximately 60 minutes or more.

7. A thermoplastic resin composition according to any one of claims 1 to 6, wherein the thermoplastic resin composition is characterized in that the haze of a 2 mm thick specimen, measured according to ASTM D1003 after being left in a 120°C oven for 24 hours, is about 10% or less.

8. A thermoplastic resin composition according to any one of claims 1 to 7, wherein the thermoplastic resin composition is characterized in that the light transmittance of a 2 mm thick specimen, measured according to ASTM D1003 after being placed in a 120°C oven for 24 hours, is about 80% or more.

9. A molded article characterized by being formed from a thermoplastic resin composition according to any one of claims 1 to 8.

10. A molded article according to claim 9, characterized in that the molded article is a transparent medical material.