阅读说明：本技术 一种聚醚醚酮毛细管在线结晶一步生产方法 (One-step online crystallization production method of polyether-ether-ketone capillary ) 是由 谭宗尚 叶云峰 吴宏勇 李军 从飞 朱冠南 冯习 于 2019-11-22 设计创作，主要内容包括：本发明涉及一种聚醚醚酮毛细管在线结晶一步生产方法,在真空定径过程中控制真空定径套中冷却腔的冷却速率,使PEEK材料缓慢冷却,PEEK分子开始重新向正规模型排列,形成结晶,同时控制挤出和牵引速度使PEEK毛细管达到35％～45％的结晶度,保证PEEK毛细管性能的同时又保证了管材的尺寸的稳定性。(The invention relates to an online crystallization one-step production method of a polyether-ether-ketone capillary tube, which is characterized in that the cooling rate of a cooling cavity in a vacuum sizing sleeve is controlled in the vacuum sizing process, so that a PEEK material is slowly cooled, PEEK molecules begin to be arranged in a normal scale again to form crystals, and the extrusion and traction speeds are controlled to enable the PEEK capillary tube to reach the crystallinity of 35-45%, so that the performance of the PEEK capillary tube is ensured, and the dimensional stability of the tube is also ensured.)

1. The online crystallization one-step production method of the polyether-ether-ketone capillary is characterized by comprising the following steps of:

adding a PEEK raw material into an extruder for melt extrusion, wherein the heating temperature of the extruder is 370-390 ℃, and PEEK melt is extruded from an outlet of a head die of the extruder, then the PEEK melt is subjected to a vacuum sizing process, and is subjected to air cooling, traction, cutting and curling to prepare a PEEK capillary tube with the crystallinity of 35-45% in one step;

the vacuum sizing process uses three vacuum sizing sleeves, the number of cooling cavities of the vacuum sizing sleeves is three, and heat-conducting media are filled in the cooling cavities to cool the PEEK;

the PEEK passing through the die outlet in the air cooling direction has the temperature of 190-210 ℃, 160-190 ℃ and 130-170 ℃ after passing through the three cooling cavities in sequence.

2. The one-step online crystallization production method of the polyetheretherketone capillary tube according to claim 1, wherein the extrusion speed and the traction speed of the extruder are both 2-4 cm/s; the air cooling is natural cooling or air cooling.

3. The one-step online crystallization production method of polyetheretherketone capillary tubes according to claim 2, wherein the extrusion speed and the pulling speed of the extruder are both 3 cm/s.

4. The one-step online crystallization production method for the PEEK capillary according to any one of claims 1 to 3, wherein the cooling rates of the PEEK in the three cooling cavities are 13-40 ℃/s, 5-16 ℃/s and 2-12 ℃/s in sequence.

5. The one-step online crystallization production method of the PEEK capillary tube according to claim 4, wherein the cooling rates of the PEEK in the three cooling cavities are 20-32 ℃/s, 6-12 ℃/s and 3-6 ℃/s in sequence.

6. The one-step online crystallization production method for the PEEK capillary tube according to claim 5, wherein the cooling rates are 20 ℃, 8 ℃/s and 6 ℃/s in sequence, and the PEEK temperature after passing through the three cooling cavities is 200 ℃, 160 ℃ and 130 ℃ in sequence.

7. The one-step online crystallization production method for the PEEK capillary tube according to claim 5, wherein the cooling rate is 20 ℃/s, 6 ℃/s and 3 ℃/s in sequence, and the temperature of the PEEK after passing through the three cooling cavities is 200 ℃, 170 ℃ and 165 ℃ in sequence.

8. The one-step online crystallization production method for the PEEK capillary tube according to any one of claims 1-3, further comprising a steam spraying operation after the vacuum sizing process, so that the cooling rate of the PEEK is 0.6-1.2 ℃/s.

9. The one-step online crystallization production method of polyetheretherketone capillary tubes according to claim 8, wherein the temperature of the steam spray is 130 ℃.

Technical Field

The invention relates to the technical field of high molecular polymers, in particular to an online crystallization one-step production method of a polyether-ether-ketone capillary tube.

Background

Polyether-ether-ketone (PEEK) is a special engineering plastic with excellent performance, has excellent heat resistance, mechanical property, chemical resistance, electrical insulation property, flame retardant property and the like, and has wide application prospect in the fields of sports, aerospace composite materials, energy industry and the like.

PEEK is a high-performance semi-crystalline polymer, the melting temperature is 370 ℃ -390 ℃, PEEK extrusion capillary has the advantages of high strength, high purity, high temperature resistance, corrosion resistance, no toxicity, self-extinguishing property and the like, and is mainly applied to analytical instruments and medical catheters at present, but the PEEK capillary on the market is amorphous PEEK at present, because the PEEK is rapidly cooled through the action of cooling water of a vacuum diameter part after being extruded by the PEEK capillary, the PEEK is rapidly cooled and shaped and cannot be crystallized, and the size of the PEEK which cannot be crystallized cannot be stable.

Disclosure of Invention

The invention provides a one-step online crystallization production method of a PEEK capillary tube, which aims to solve the technical problem that the PEEK capillary tube cannot be crystallized before being shaped.

In order to achieve the purpose, the invention is realized by the following technical scheme:

an online crystallization one-step production method of a polyether-ether-ketone capillary tube comprises the following steps:

adding a PEEK raw material into an extruder for melt extrusion, wherein the heating temperature of the extruder is 370-390 ℃, and PEEK melt is extruded from an outlet of a head die of the extruder, then the PEEK melt is subjected to a vacuum sizing process, and is subjected to air cooling, traction, cutting and curling to prepare a PEEK capillary tube with the crystallinity of 35-45% in one step;

the vacuum sizing process uses three vacuum sizing sleeves, the number of cooling cavities of the vacuum sizing sleeves is three, and heat-conducting media are filled in the cooling cavities to cool the PEEK;

the PEEK passing through the die outlet in the air cooling direction has the temperature of 190-210 ℃, 160-200 ℃ and 130-170 ℃ after passing through the three cooling cavities in sequence.

Further, the extrusion speed and the traction speed of the extruder are both 2-4 cm/s; the air cooling is natural cooling or air cooling.

Further, the extrusion speed and the traction speed of the extruder are both 3 cm/s.

Furthermore, the cooling rates of the PEEK in the three cooling cavities are 13-40 ℃/s, 5-16 ℃/s and 2-12 ℃/s in sequence.

Preferably, the cooling rates of the PEEK in the three cooling cavities are 20-32 ℃/s, 6-12 ℃/s and 3-6 ℃/s in sequence.

Preferably, the cooling rate is 20 ℃, 8 ℃/s and 6 ℃/s in sequence, and the temperature of PEEK after passing through the three cooling cavities is 200 ℃, 160 ℃ and 130 ℃ in sequence.

Preferably, the cooling rate is 20 ℃/s, 6 ℃/s and 3 ℃/s in sequence, and the temperature of PEEK after passing through the three cooling cavities is 200 ℃, 170 ℃ and 165 ℃ in sequence.

Further, the vacuum sizing process is followed by a steam spraying operation so that the cooling rate of the PEEK is 0.6-1.2 ℃/s.

Further, the temperature of the steam shower is 130 ℃.

The beneficial technical effects are as follows: when the PEEK melt is extruded from the outlet of the neck mold and enters the vacuum sizing process, the PEEK melt becomes a PEEK capillary tube, and in the prior art, the vacuum sizing sleeve uses cooling water to carry out extremely-fast cooling on the capillary tube, so that PEEK molecules have no tendency of normal-scale arrangement, and the PEEK capillary tube is still in an amorphous state although being cooled and sized. The invention controls the cooling rate of the cooling cavity in the vacuum sizing sleeve in the vacuum sizing process of the PEEK material, so that the PEEK is slowly cooled, PEEK molecules are arranged in a positive scale to form crystals, and the extrusion and traction speeds are controlled to ensure that the PEEK capillary tube reaches 35-45% of crystallinity, thereby ensuring the performance of the PEEK capillary tube and the dimensional stability of the tube.

Drawings

FIG. 1 is a process flow diagram of the one-step online crystallization method for producing PEEK capillary according to example 1.

FIG. 2 is a process flow diagram of the one-step online crystallization method for producing PEEK capillary according to example 2.

FIG. 3 is a process flow diagram of the one-step online crystallization method for producing PEEK capillary according to example 3.

Detailed Description

The invention is further described below with reference to the figures and specific examples, without limiting the scope of the invention.