A pet composition, its preparation and use

Abstract

The application discloses a PET composition, which comprises the following components in parts by weight: PET 51-61 parts; PETG 5-15 parts; carboxyl-terminated hyperbranched polyester 1-5 parts; glass fiber 25-35 parts; nucleating agent 0.2-0.8 parts. By adding specific amounts of PETG, hyperbranched polyester and nucleating agent, the screw column torque performance of the PET composition can be significantly improved, and the high screw column torque is obtained, so that the PET composition is suitable for preparing household appliances, electronic appliances and other products requiring screw installation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high molecular materials, in particular to a PET composition, a preparation method and application thereof. BACKGROUND

[0002] Polyethylene terephthalate (PET) is a semi-crystalline thermoplastic polyester. The modification of PET mainly includes reinforcement modification. Under conventional conditions, glass fibers are needed to modify PET to improve its practical applicability. The PET product modified by reinforcement is applied to the household appliance industry (such as drying channels and air fryers), and needs to have good temperature resistance and good mechanical properties (such as high impact strength) to meet the functional test of the product. At the same time, since this kind of product has more or less certain screw holes, it needs to be assembled by self-tapping screws, and requires no cracking during the self-tapping process. SUMMARY

[0003] The present application aims to provide a PET composition with good notched impact strength and high torque.

[0004] The present application is achieved by the following technical solutions:

[0005] A PET composition, by weight, comprises the following components:

[0006] PET 51-61 parts;

[0007] PETG 5-15 parts;

[0008] Carboxyl-terminated hyperbranched polyester 1-5 parts;

[0009] Glass fiber 25-35 parts;

[0010] Nucleating agent 0.2-0.8 parts.

[0011] The nucleating agent is selected from at least one of sodium humate and talc; preferably, the nucleating agent is selected from sodium humate and talc, and the weight ratio of sodium humate to talc is 1: (1.5-3.6).

[0012] The average particle size of the talc is 2-10 microns. The average particle size of the talc is tested by a laser particle size instrument.

[0013] The number of carboxyl end groups per mole of carboxyl-terminated hyperbranched polyester in the carboxyl-terminated hyperbranched polyester is 6-48 mol, and the number average molecular weight is 900-12500 g / mol; preferably, the number of carboxyl end groups per mole of carboxyl-terminated hyperbranched polyester in the carboxyl-terminated hyperbranched polyester is 12-24 mol, and the number average molecular weight is 2100-6400 g / mol.

[0014] The end carboxyl hyperbranched polyester can be at least one of an aromatic polyester polyether structure, an aromatic polyester structure. Preferably, the end carboxyl hyperbranched polyester is selected from an aromatic polyester polyether structure.

[0015] The intrinsic viscosity of the PET is in the range of 0.6-0.8 dL / g, and the intrinsic viscosity detection standard is method A in 5.1.1 of GB / T 14190-2017.

[0016] The intrinsic viscosity of the PETG is in the range of 0.6-0.8 dL / g, and the viscosity detection standard is ISO 1628-5-2015.

[0017] The average diameter of the glass fiber is in the range of 10-13 microns.

[0018] 0-2 parts of an auxiliary agent can be selected according to actual needs; the auxiliary agent is selected from at least one of a lubricant, an antioxidant, and a colorant.

[0019] The preparation method of the PET composition of the present application comprises the following steps: uniformly mixing the components according to the ratio, and extruding and granulating through a double-screw extruder, the barrel temperature is in the range of 220-270 DEG C, and the screw rotation speed is in the range of 250-400 revolutions / minute, to obtain the PET composition.

[0020] The application of the PET composition of the present application is used for preparing products such as drying channels, air fryers, etc. that need to be installed by self-tapping screws.

[0021] The present application has the following beneficial effects:

[0022] In the PET, the PETG required is added to inhibit the crystallization of the PET resin, so that the front end of the melt does not cool too fast when the product is injection molded, and the two melts can be well fused when they converge, so as to improve the bonding force of the screw column bonding part, and further improve the torque of the screw column; at the same time, a specific end carboxyl hyperbranched polyester (limited carboxyl number and molecular weight) is introduced into the system, and its addition amount is controlled, the end carboxyl hyperbranched polyester can react with the end hydroxyl group of the PET resin to form a partial micro-crosslinking structure, which provides high toughness to the system, can well absorb the energy when the self-tapping screw is tapped, and due to the presence of the end carboxyl hyperbranched polyester, the flowability of the system can be greatly improved, the impregnation and wrapping of the glass fiber are increased, the combination of the resins is more favorable when the melts converge, and thus the bonding force of the screw column bonding part is improved, thereby improving the torque of the screw column. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 : Schematic diagram of the screw column sample before and after testing in the failure torque test. Detailed Implementation

[0024] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention. These all fall within the scope of protection of the present invention.

[0025] The sources of the raw materials used in the embodiments and comparative examples of this invention are as follows:

[0026] PET: Intrinsic viscosity 0.64 dL / g, PET WK631, Wankai New Materials Co., Ltd.;

[0027] PETG-1: Intrinsic viscosity 0.65 dL / g, FLOW™ 65, Selenis Portugal, SA;

[0028] PETG-2: Intrinsic viscosity 0.7 dL / g, PETG GN821, Sinopec Yizheng Chemical Fiber Co., Ltd.;

[0029] PETG-3: Intrinsic viscosity 1.15 dL / g, GEO™ LF 451, Selenis Portugal, SA;

[0030] HyPer C101: An aromatic polyester polyether structure with terminal carboxyl hyperbranched polyester, with 6 mol of carboxyl groups per mole of terminal carboxyl hyperbranched polyester and a number-average molecular weight of 1000 g / mol.

[0031] HyPer C102: An aromatic polyester polyether structure with terminal carboxyl hyperbranched polyester, with 12 mol of carboxyl groups per mole of terminal carboxyl hyperbranched polyester and a number-average molecular weight of 2600 g / mol.

[0032] HyPer C103: An aromatic polyester polyether structure with terminal carboxyl hyperbranched polyester, with 24 mol of carboxyl groups per mole of terminal carboxyl hyperbranched polyester and a number-average molecular weight of 6400 g / mol.

[0033] HyPer C104: An aromatic polyester polyether structure with terminal carboxyl hyperbranched polyester, with 48 mol of carboxyl groups per mole of terminal carboxyl hyperbranched polyester and a number-average molecular weight of 12000 g / mol.

[0034] HyPer C201: An aromatic polyester with terminal carboxyl hyperbranched polyester structure, with 6 mol of carboxyl groups per mole of terminal carboxyl hyperbranched polyester and a number-average molecular weight of 950 g / mol.

[0035] HyPer C202: aromatic polyester structure end carboxyl hyperbranched polyester, the number of carboxyl groups per mole of end carboxyl hyperbranched polyester is 12 mol, the number average molecular weight is 2100 g / mol;

[0036] HyPer C203: aromatic polyester structure end carboxyl hyperbranched polyester, the number of carboxyl groups per mole of end carboxyl hyperbranched polyester is 24 mol, the number average molecular weight is 5200 g / mol;

[0037] HyPer C204: aromatic polyester structure end carboxyl hyperbranched polyester, the number of carboxyl groups per mole of end carboxyl hyperbranched polyester is 12 mol, the number average molecular weight is 11000 g / mol;

[0038] HyPer H302: aromatic polyester structure end hydroxyl hyperbranched polyester, the number of hydroxyl groups per mole of end hydroxyl hyperbranched polyester is 12 mol, the number average molecular weight is 2500 g / mol;

[0039] HyPer H303: aromatic polyester structure end hydroxyl hyperbranched polyester, the number of hydroxyl groups per mole of end hydroxyl hyperbranched polyester is 24 mol, the number average molecular weight is 2500 g / mol;

[0040] Glass fiber: diameter 11 um, fiberglass ECS11-4.5-534A, China Jushi Co., Ltd.;

[0041] Sodium lignate: LICOMONT NAV101 PWD, Guangzhou Fentian Chemical Co., Ltd.;

[0042] Talc powder: SDC-9489, average particle size about 5 microns, Liaoning Xida Talc Group Co., Ltd.;

[0043] Lubricant: pentaerythritol tetrastearate, PETS-AP, Fajia Asia Pacific Private Limited.

[0044] Preparation method of PET composition of examples and comparative examples: according to the ratio, mix each component uniformly, extrude and granulate through a double screw extruder, the temperature of each barrel of the double screw extruder from the feeding port to the die head is respectively: 220-240℃, 230-250℃, 230-250℃, 230-250℃, 240-260℃, 240-260℃, 240-260℃, 250-270℃, 250-270℃, 250-270℃, the screw rotation speed range is 250-400 revolutions per minute, to obtain the PET composition.

[0045] Test methods:

[0046] (1) Notched impact strength: test standard ISO 180-2019, pendulum energy: 2.75 J.

[0047] (2) Failure torque: dry the material at 120℃ / 4h, and inject the screw column sample at 270℃ (screw column mold inner diameter 3.2mm, outer diameter 10.0mm), use standard M4 screw, use screw column torque screw machine to screw, test the failure torque (unit N*m) of the screw column sample.

[0048] Table 1: weight parts of each component of PET composition of examples 1-6 and test results

[0049] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 PET 51 55 61 55 55 55 PETG-1 5 10 10 10 10 PETG-2 15 HyPer C101 1 3 5 HyPer C102 3 HyPer C103 3 HyPer C104 3 Glass fiber 25 30 35 30 30 30 Sodium montanate 0.05 0.125 0.2 0.125 0.125 0.125 Talc 0.15 0.375 0.6 0.375 0.375 0.375 Lubricant 0.5 0.5 Notched Charpy impact strength, kJ / m 2 ]] 10.2 11.8 12.3 13.2 14.1 12.1 Failure torque N*m 2.85 3.12 3.22 3.82 3.91 3.23

[0050] Table 2: weight parts of each component of PET composition of examples 7-10 and test results

[0051] Example 7 Example 8 Example 9 Example 10 PET 55 55 55 55 PETG-1 10 10 10 10 HyPer C201 3 HyPer C202 3 HyPer C203 3 HyPer C204 3 Glass fiber 30 30 30 30 Sodium montanate 0.125 0.125 0.125 0.125 Talc 0.375 0.375 0.375 0.375 Notched Charpy impact strength, kJ / m 2 ]] 11.1 12.7 13.7 11.4 Failure torque N*m 3.02 3.64 3.71 3.05

[0052] From examples 2 / 4-10, it is known that the number of terminal carboxyl groups of the terminal carboxyl hyperbranched polyester is preferably 12-24 mol, and the molecular weight is 2100-6400g / mol; and, the aromatic polyester polyether structure is preferred.

[0053] Table 3: weight parts of each component of PET composition of examples 11-14 and test results

[0054] Example 11 Example 12 Example 13 Example 14 PET 55 55 55 55 PETG-1 10 10 10 10 HyPer C201 3 3 3 3 Glass fiber 30 30 30 30 Sodium montanate 0.2 0.11 0.5 Talc 0.3 0.39 0.5 Notched Charpy impact strength, kJ / m 2 ]] 10.4 10.8 10.0 9.1 Failure torque N*m 2.91 2.97 2.77 2.62

[0055] From examples 7 / 11-14, it is known that the weight ratio of nucleating agent sodium montanate: talc is preferably 1: (1.5-3.5).

[0056] From the above examples, it is known that the notched impact strength of the PET composition of the present application is >9 kJ / m 2 , and the failure torque is >2.5N*m

[0057] Table 4: weight parts of each component of PET composition of comparative examples and test results

[0058] Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 PET 55 55 55 55 55 55 55 PETG-1 10 10 3 22 10 10 PETG-3 10 HyPer C101 3 3 3 0.5 7 HyPer H302 3 HyPer H303 3 Glass fiber 30 30 30 30 30 30 30 Sodium montanate 0.125 0.125 0.125 0.125 0.125 0.125 0.125 Talc 0.375 0.375 0.375 0.375 0.375 0.375 0.375 Notched Charpy impact strength, kJ / m 2 ]] 5.5 4.9 4.5 6.2 5.8 5.2 5.6 Failure torque N*m Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 PET PETG-1 PETG-3 HyPer C101 HyPer H302 HyPer H303 Glass fiber Sodium montanate Talc Failure torque N*m Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 PET PETG-1 PETG-3 HyPer C101 HyPer H302 HyPer H303 Glass fiber Sodium montanate Talc Failure torque N*m 1.31 1.13 0.82 1.55 1.43 1.25 1.56

[0059] From comparative example 1, it is known that when the intrinsic viscosity of PETG is too high, the notched impact strength and failure torque of the PET composition are both very low.

[0060] From comparative examples 2 / 3, it is known that the terminal hydroxyl hyperbranched polyester cannot achieve the purpose of the present application.

[0061] From comparative examples 4 / 5, it is known that when the content of PETG is too low or too high, the notched impact strength and failure torque of the PET composition are both very low.

[0062] From comparative examples 6 / 7, it is known that when the content of hyperbranched polyester is too low or too high, the failure torque will be significantly reduced.

Claims

1. A PET composition, characterized in that, By weight, it includes the following components: PET 51-61 portions; PETG 5-15 servings; 1-5 parts of carboxyl-terminated hyperbranched polyester; 25-35 parts glass fiber; Nucleating agent 0.2-0.8 parts; The number of terminal carboxyl groups per mole of the terminal carboxyl hyperbranched polyester is 6-48 mol, and the number average molecular weight is 900-12500 g / mol. The intrinsic viscosity range of the PETG is 0.6-0.8 dL / g.

2. The PET composition according to claim 1, characterized in that, The nucleating agent is selected from at least one of sodium lignite and talc.

3. The PET composition according to claim 2, characterized in that, The nucleating agent is selected from sodium lignite and talc, with a weight ratio of sodium lignite:talc = 1:(1.5-3.6).

4. The PET composition according to claim 2, characterized in that, The average particle size of the talc powder is 2-10 micrometers.

5. The PET composition according to claim 1, characterized in that, The carboxyl-terminated hyperbranched polyester is selected from at least one of aromatic polyester polyether structure and aromatic polyester structure.

6. The PET composition according to claim 5, characterized in that, The carboxyl-terminated hyperbranched polyester has an aromatic polyester polyether structure.

7. The PET composition according to claim 1, characterized in that, The terminal carboxyl hyperbranched polyester has 12-24 mol of terminal carboxyl groups per mole and a number-average molecular weight of 2100-6400 g / mol.

8. The PET composition according to claim 1, characterized in that, The intrinsic viscosity range of the PET is 0.6-0.8 dL / g.

9. The PET composition according to claim 1, characterized in that, The average diameter of the glass fiber is in the range of 10-13 micrometers.

10. The PET composition according to claim 1, characterized in that, The product also includes 0-2 parts by weight of additives; the additives are selected from at least one of lubricants, antioxidants, and colorants.

11. A method for preparing the PET composition according to any one of claims 1-10, characterized in that, The process includes the following steps: mixing the components evenly according to the formula, granulating the mixture by extrusion through a twin-screw extruder, with a barrel temperature range of 220-270℃ and a screw speed range of 250-400 rpm, to obtain a PET composition.

12. The use of the PET composition according to any one of claims 1-10, characterized in that, Used for manufacturing products for home appliances and electronic devices that have screw posts and require self-tapping screws for installation.

Images