Application of PTFE lining pipe  in minimally invasive medicine

The PTFE lining pipe is designed using polytetra fluoroethylene polymer due to its special functions. The reason why polytetrafluoroethylene is used as a catheter liner is because it has a smooth, low friction surface, which helps reduce the risk of infection and tissue damage. They also have biocompatibility, so most people will not experience allergic reactions or any adverse reactions. However, polytetrafluoroethylene cannot be melted, but professionals have developed a form that can be melted, known as FEP. FEP is fluorinated ethylene propylene, which has exactly the same characteristics as PTFE, but with low heat shrinkage temperature and UV resistance, making it very suitable for designing products that require high transparency, chemical resistance, and relatively low hardness. In addition, due to PTFE’s tendency to slip, it may require etching in certain situations. This etched PTFE is easy to bond with other polymers and can be used in various manufacturing processes. A mixture of sodium and ammonia can be used for PTFE etching. Therefore, these are the reasons why it has become a well-known commercial polymer.

The wide applications of PTFE inner lining tubes include: guide tubes, deflectable tubes, controllable tubes, equipment conveying systems, etc Waiting for various purposes!

PTFE lining pipe: amazing benefits!

In recent years, PTFE lining pipe has brought revolutionary changes to the medical field. These liners can be used for various medical surgeries, including joint replacement surgery and cardiovascular intervention surgery.

① The PTFE lining pipe is very durable and can withstand extreme temperatures, making it very suitable for minimally invasive medical surgeries.

② The PTFE lining pipe can be easily molded into any shape, making it suitable for complex medical surgeries.

③ These linings are made of Teflon, which is known for its strength and non adhesiveness, making it very suitable for use in sensitive medical environments.
④ PTFE lining pipe is also resistant to most chemicals, making it a safer choice for the production of medical equipment or components.
⑤ They are extremely lightweight, easy to install in narrow areas with limited channels, and can be used for many different types of medical equipment.
⑥ They provide excellent protection during frequent use, preventing severe wear and tear. This makes them suitable for medical equipment such as catheters, stents, and wires, as these tools require reliable protection to prevent wear and damage.

Common resistoflex   PTFE lining pipe product processing – CHINA Aokeray
The production methods of PTFE liner currently mainly include immersion coating process, free extrusion process, and core shaft extrusion process. PTFE liner products produced by different processes also have slightly different product characteristics; As a manufacturer, AOKERAY’s unique preparation process procedure focuses on:

① Production process: Dip coating production process – surface etching treatment!

Features of PTFE Liner with core shaft immersion coating (Aokeray common product features: minimum wall thickness of 0.0002 ”, ID: 0.3-3.0mm)

② Production process: Free extrusion process – surface etching treatment;

Aokeray Medical Free Extrusion PTFE Liner Product Features: Minimum wall thickness is 0.001 ”, ID: 0.026 “to 0.445” (0.66mm to 11.3mm); In practical applications, the inner diameter size can be customized according to the actual size in different situations!

③ Production process: extrusion with core shaft and free extrusion process – surface etching treatment or surface with ultra-thin thermoplastic bonding layer;

Common features and levels of Aokeray products: (1) extrusion with a core shaft – surface etching treatment;

1) The wall thickness is 0.001 “, ID: 0.012” to 0.092 “(0.305mm to 2.337mm), and the wall thickness tolerance is 0.00025” (0.00635mm);

2) The wall thickness is 0.00075 “, ID: 0.012” to 0.092 “(0.305mm to 2.337 mm), with a wall thickness tolerance of 0.00025” (0.00635mm);

3) The wall thickness is 0.0005 “, ID: 0.012” to 0.042 “(0.305mm to 1.067mm), with a wall thickness tolerance of 0.00025″ (0.00635mm);

(2) Production process: Dip coating production process – surface etching treatment or surface with ultra-thin thermoplastic bonding layer;

Common product features and levels of AOkeray:

The minimum single wall thickness is 0.0003 ”, ID: 0.002 ” -0.0910 ” (0.508mm -2.311mm); The wall thickness tolerance is 0.00019 ” (0.005mm)

Characteristics of thermoplastic bonding layer: The presence of the bonding layer can improve the bonding force between the inner lining pipe and the outer pipe of the conduit after the rheological process. At the same time, the inner lining pipe with the bonding layer can increase the fracture force by 40%. The thickness of the thermoplastic bonding layer is about 0.004mm.

Fluorinated polymer etching treatment
PTFE Liner will turn brown after etching, as detailed in the article on PTFE Liner etching treatment. The following image shows a comparison of photos of PTFE Liner before and after etching treatment. In fact, PTFE Liner after extrusion or immersion coating is milky white or slightly transparent color (as shown in Figure 1), which will turn brown after chemical etching

Q1: Why is it necessary to etch fluoropolymer pipe fittings?

Fluorinated polymers such as PTFE, FEP, and PFA (often referred to as Teflon) are very smooth. This lubricity and the composition of fluorinated polymers reduce their adhesion; Etching treatment can alter the surface properties of fluorinated polymers, allowing them to bond with conventional polymer adhesives;

Q2: How to perform etching treatment?

Etching is the stripping of fluorine molecules from the carbon chains of fluorinated polymers by sodium solutions and fluorinated pipe surfaces, resulting in insufficient electron numbers of carbon atoms. When the etched material comes into contact with air, oxygen molecules, water vapor, and hydrogen can reduce electrons. The result of this reduction process is the formation of a group of organic molecules responsible for adsorption tasks; Thus achieving the final etching effect;

Q3: Will etching treatment change the performance of pipe fittings?

The etching process only acts on the surface at a depth of a few nanometers, so it has almost no effect on the performance of the pipe fittings and has almost no effect on the size of the pipe fittings; However, the etching process can cause the material surface to turn black, usually with a slight brown or brownish color, and the etching process can also reduce the lubrication of the pipe surface;

Q4: How to store etched fluoropolymer pipe fittings?

Fluorinated polymers that have been etched will be “stripped” of molecules in the air to repair their electron deficiency, which can lead to a decrease in surface etching performance. Therefore, all etching materials should be stored in their original black sealed bags to avoid being exposed to ultraviolet radiation and reducing performance;

Q5: Does the darker surface color of the etched pipe fittings indicate better etching effect?

Not necessarily, color is not an absolute indicator of etching quality. For this reason, suppliers will provide etching certificates with each shipment of etched pipe fittings;

Q6: How to test the etching effect?

The etching material is tested using the contact angle method, and the measured contact angle of droplets on the collective surface is used to verify the wettability of the surface, as shown in the following figure: the contact angle is defined as the angle between the substrate support surface and the tangent line between the droplet and the substrate contact point. In the figure, “B” has a better etching effect than “A”;

Manufacturers generally conduct contact angle testing on etched pipe fittings and provide a certificate of conformity along with the material. If customers require it, they can also request the supplier to provide test results;

Q7: What is the shelf life of etched pipe fittings?

If stored properly, the shelf life of many etched products is almost unlimited, but purchased products should comply with good inventory regulations, be used in order of inventory, and be required to be used up as soon as possible.

The most commonly used etched pipe fittings for vascular intervention catheters are PTFE Liner, which can customize products with specific inner and outer diameters and wall thicknesses according to specific applications. Currently, high-quality products are mainly imported from abroad.