CN110975112B - Preparation method of balloon catheter - Google Patents

Abstract

The invention provides a preparation method of a balloon catheter, which comprises the following steps: performing a saccule, namely passing a saccule material pipe through a gauge with the inner diameter of 0.4mm-0.7mm, thinning two ends of the saccule material pipe, and reserving a bubble length with the bubble length ratio of 40% -60% in the middle to obtain a preformed saccule; and (3) balloon molding, namely placing the preformed balloon into a balloon mold for blow molding, and injecting nitrogen into the preformed balloon, wherein the temperature of the balloon mold is controlled at 110-400 psi and the pressure of the nitrogen in the preformed balloon is controlled at 350-400 ℃. The balloon catheter 1 obtained by adopting the technical scheme has the advantages that the balloon can reach the nominal diameter under the pressure of 4atm, the wall adhesion of the balloon can be realized under the specific lower pressure, and the double-layer wall thickness of the balloon is ultrathin and is only 0.0008-0.0009 inch. The diameter of the balloon is ultra-small after the three wings are folded, and the balloon can easily reach the position of a lesion through a tortuous intracranial blood vessel. 3. The balloon bursting pressure is about 12atm-14atm, which can greatly reduce the injury to intracranial vessels when the balloon is broken.

Description

Preparation method of balloon catheter

Technical Field

The invention relates to the technical field of medical instruments, in particular to a preparation method of a balloon catheter.

Background

In the process of intracranial neurovascular intervention, the catheter cannot smoothly pass through pathological changes and balloon rupture to have adverse effects on the cerebral vessels, which is a problem faced by most products. The reason is that the high-pressure compliance saccule is used for most intracranial nerve catheters on the market, and the saccule has the following defects clinically:

1. the double-layer wall thickness of the balloon is thicker, and the outer diameter is relatively larger after the balloon is folded. The pushing force is poor in the operation process, and the intracranial vascular lesion is not easy to pass through.

2. The balloon nominal diameter filling pressure is higher, the balloon can be filled to the nominal diameter only under the pressure of 6atm, and the pressure when the balloon is burst is higher. Intracranial vessels are fragile and can be damaged when they are ruptured by high pressure.

Disclosure of Invention

It is an object of the present invention to provide a low pressure compliant balloon catheter.

The technical scheme of the invention is as follows:

a method of making a balloon catheter comprising the steps of:

1. preparing balloon granules:

the preparation of the balloon granules comprises the following steps

S1: stirring and reacting polyester and polyether for 3 hours under the protection of nitrogen, and controlling the temperature at 80 ℃ to obtain a prepolymer;

s2: heating the prepolymer to 90 ℃, adding molten polyamide, and stirring for 30 min;

s3: and plasticizing for 4 hours at 75 ℃ after discharging to obtain the balloon granules.

The balloon material pipe is formed by extruding balloon granules through an extruder, and the weight ratio of polyurethane, polyester and polyether in the balloon granules is 4:2: 3.

In the preparation of the granules, the proportion of polyamide, polyester and polyether is different, and the hardness of the extruded balloon tube is different, so that the compliance of the formed balloon is influenced. The weight ratio of polyurethane, polyester and polyether in the balloon granules is 4:2:3, and the hardness of the obtained balloon material pipe is 70-75A, which is acceptable.

2. Extrusion of balloon material tubes

The preparation method of the balloon material tube comprises the following steps:

s1: vacuum drying the balloon granules of polyurethane, polyester and polyether in a weight ratio of 4:2:3 at 50 ℃ for 5 hours, adding the dried balloon granules into an extruder, and extruding a balloon tube with the inner diameter of 0.5mm and the outer diameter of 1.0 mm;

s2: after the sacculus tube is extruded, the sacculus tube is cooled and shaped by the water jacket to form the sacculus tube.

3. Balloon molding

The method comprises the following steps:

s1: performing a saccule, namely passing a saccule material pipe through a gauge with the inner diameter of 0.4mm-0.7mm, thinning two ends of the saccule material pipe, and reserving a bubble length with the bubble length ratio of 40% -60% in the middle to obtain a preformed saccule;

s2: and (3) balloon molding, namely placing the preformed balloon into a balloon mold for blow molding, and injecting nitrogen into the preformed balloon, wherein the temperature of the balloon mold is controlled at 110-400 psi and the pressure of the nitrogen in the preformed balloon is controlled at 350-400 ℃.

Preferably, in the S1 balloon preforming step, the bubble length ratio is 45%.

One end of the sacculus material pipe is thinned by a pliers, the oversize is inserted, the exposed part is pulled out by the pliers, and the thinning of one end of the sacculus material pipe is realized. In the same manner, the other end was thinned. In the middle part, bubbles are formed, and the bubble length ratio is the bubble length: the length of the balloon.

The pre-formed balloon has different bubble lengths and different wall thicknesses after balloon blow molding, and accordingly the balloon explosion pressure is affected. Comparing the bubble length by 40% and the bubble length by 60%, after the balloon is blow-molded, the ratio of the wall thickness of the former double layer to the wall thickness of the latter double layer is 3:5, and the ratio of the bursting pressure is 14: 17. The present invention tends to have a lower bubble length in the normal range and a thinner wall thickness for the blown balloon. Bubble length is 45%, the double-layer wall thickness of the balloon fluctuates within the range of 0.0008-0.0009 inches, the nominal pressure can reach 4atm, and the bursting pressure is 11atm-12atm, which is considered as an ideal conclusion

The extrusion conditions of the extruder in S1 in the preparation method of the balloon material tube are as follows: the temperature of the feeding section of the extruder cylinder is controlled to be 215 ℃ plus or minus 5 ℃, the temperature of the compression section is controlled to be 220 ℃ plus or minus 5 ℃, the temperature of the metering section is controlled to be 220 ℃ plus or minus 5 ℃, the temperature of the head part is controlled to be 215 ℃ plus or minus 5 ℃, and the screw rotation speed is 10 r/min.

In the preparation method of the balloon material tube, the cooling parameters of water jacket cooling in S2 are as follows: the cooling water temperature is 20 ℃, and the traction speed is 600cm/min under the condition that the screw rotation speed is 10.6 r/min.

The invention has the advantages and positive effects that: by adopting the technical scheme, the obtained balloon catheter

1. The balloon can reach the nominal diameter only under the pressure of 4atm, and the adherence of the balloon can be realized at lower pressure

2. The double-layer wall thickness of the balloon is ultrathin and is only 0.0008-0.0009 inches. The diameter of the balloon is ultra-small after the three wings are folded, and the balloon can easily reach the position of a lesion through a tortuous intracranial blood vessel.

3. The balloon bursting pressure is about 12atm-14atm, which can greatly reduce the injury to intracranial vessels when the balloon is broken.

Detailed Description

Example 1

A method of making a balloon catheter comprising the steps of:

1. preparing balloon granules:

the preparation of the balloon granules comprises the following steps

S1: stirring polyester and polyether in a weight ratio of 2:3 for reaction for 3 hours under the protection of nitrogen, and controlling the temperature to be 80 ℃ to obtain a prepolymer;

s2: heating the prepolymer to 90 ℃, adding molten polyamide with the mass 2 times that of the polyester in S1, and stirring for 30 min;

s3: and plasticizing for 4 hours at 75 ℃ after discharging to obtain the balloon granules.

2. Extrusion of balloon material tubes

The preparation method of the balloon material tube comprises the following steps:

s1: vacuum drying the balloon granules at 50 ℃ for 5h, adding the dried balloon granules into an extruder, and extruding a balloon tube with the inner diameter of 0.5mm and the outer diameter of 1.0 mm;

s2: after the sacculus tube is extruded, the sacculus tube is cooled and shaped by the water jacket to form the sacculus tube.

The extrusion conditions of the extruder in S1 in the preparation method of the balloon material tube are as follows: the temperature of the feeding section of the extruder cylinder is controlled to be 215 ℃ plus or minus 5 ℃, the temperature of the compression section is controlled to be 220 ℃ plus or minus 5 ℃, the temperature of the metering section is controlled to be 220 ℃ plus or minus 5 ℃, the temperature of the head part is controlled to be 215 ℃ plus or minus 5 ℃, and the screw rotation speed is 10 r/min.

In the preparation method of the balloon material tube, the cooling parameters of water jacket cooling in S2 are as follows: the cooling water temperature is 20 ℃, and the traction speed is 600cm/min under the condition that the screw rotation speed is 10.6 r/min.

3. Balloon molding

The method comprises the following steps:

s1: performing a saccule, namely passing a saccule material pipe through a gauge with the inner diameter of 0.4mm-0.7mm, thinning two ends of the saccule material pipe, and reserving a bubble length with the bubble length ratio of 40% -60% in the middle to obtain a preformed saccule; one end of the sacculus material pipe is thinned by a pliers, the oversize is inserted, the exposed part is pulled out by the pliers, and the thinning of one end of the sacculus material pipe is realized. In the same manner, the other end was thinned.

S2: and (3) balloon molding, namely placing the preformed balloon into a balloon mold for blow molding, and injecting nitrogen into the preformed balloon, wherein the temperature of the balloon mold is controlled at 110-400 psi and the pressure of the nitrogen in the preformed balloon is controlled at 350-400 ℃.

The performance parameters of the obtained balloon catheter are as follows

3.0 × 20 gauge balloon size and performance

Performance parameters of balloon catheters of different bubble length ratios

Performance parameters of balloon catheter at nitrogen pressure and mold temperature of example 1

While one embodiment of the present invention has been described in detail, the description is only a preferred embodiment of the present invention and should not be taken as limiting the scope of the invention. All equivalent changes and modifications made within the scope of the present invention shall fall within the scope of the present invention.

Claims (4)

1. A method of making a balloon catheter, comprising the steps of:

s1: performing a saccule, namely passing a saccule material pipe through a gauge with a specific inner diameter of 0.4mm-0.7mm, thinning two ends of the saccule material pipe, and reserving a bubble length with a bubble length ratio of 40% -60% in the middle to obtain a preformed saccule;

s2: balloon molding, namely placing the preformed balloon into a balloon mold for blow molding, and injecting nitrogen into the preformed balloon, wherein the temperature of the balloon mold is controlled to be 110-400 psi and the pressure of the nitrogen in the preformed balloon is controlled to be 350-400 ℃ respectively,

the balloon material pipe is formed by extruding balloon granules through an extruder, the weight ratio of polyurethane to polyester to polyether in the balloon granules is 4:2:3,

the preparation of the balloon granules comprises the following steps:

s1: stirring and reacting polyester and polyether for 3 hours under the protection of nitrogen, and controlling the temperature at 80 ℃ to obtain a prepolymer;

s2: heating the prepolymer to 90 ℃, adding molten polyamide, and stirring for 30 min;

s3: plasticizing for 4h at 75 ℃ after discharging to obtain balloon granules,

the preparation method of the balloon material tube comprises the following steps:

s1: vacuum drying the balloon granules of polyurethane, polyester and polyether in a weight ratio of 4:2:3 at 50 ℃ for 5 hours, adding the dried balloon granules into an extruder, and extruding a balloon tube with the inner diameter of 0.5mm and the outer diameter of 1.0 mm;

s2: after the sacculus tube is extruded, the sacculus tube is cooled and shaped by the water jacket to form the sacculus tube.

2. The method for producing a balloon catheter according to claim 1, characterized in that: the bubble length ratio in S1 was 45%.

3. The method for producing a balloon catheter according to claim 1, characterized in that: the extrusion conditions of the extruder in S1 in the preparation method of the balloon material tube are as follows: the temperature of the feeding section of the extruder cylinder is controlled to be 215 ℃ plus or minus 5 ℃, the temperature of the compression section is controlled to be 220 ℃ plus or minus 5 ℃, the temperature of the metering section is controlled to be 220 ℃ plus or minus 5 ℃, the temperature of the head part is controlled to be 215 ℃ plus or minus 5 ℃, and the screw rotation speed is 10 r/min.

4. The method for producing a balloon catheter according to claim 1, characterized in that: in the preparation method of the balloon material tube, the cooling parameters of water jacket cooling in S2 are as follows: the cooling water temperature is 20 ℃, and the traction speed is 600cm/min under the condition that the screw rotation speed is 10.6 r/min.