CN107573660A - A kind of low temperature FDM types biological medical degradable 3D printing material, preparation and application - Google Patents

Abstract

A low-temperature FDM biomedical degradable 3D printing material, its preparation and application, belong to the field of 3D printing. The material uses PCL, starch (potato starch, corn starch or soluble starch, etc.), EBS, SiO ₂ , magnesium stearate as raw materials, and the preparation method is to combine PCL masterbatch with starch, EBS, SiO ₂ , hard Magnesium fatty acid and other fillers are melted and mixed according to a certain proportion, crushed and granulated, then extruded through a single screw, stretched into a wire with uniform size and suitable size, and then printed with an FDM 3D printer. The process of the invention is simple and easy, the preparation cost is low, the printing precision is high, and it has low requirements for 3D printing equipment and wide selectivity, and the general household FDM 3D printer can also be used, and the material is degradable, and it is a great tool for the development of biological Medical FDM 3D printing materials provide the basis and have important value and significance in the field of 3D printing.

Description

A low-temperature FDM biomedical degradable 3D printing material, preparation and application

technical field

The invention belongs to the field of 3D printing, and in particular relates to the preparation of a biomedical degradable low-temperature FDM 3D printing material and its application printing conditions.

Background technique

Fused deposition modeling (FDM, Fused Deposition Modeling), this process is to extrude filamentous materials such as thermoplastics, wax or metal fuses from heated nozzles, and follow the predetermined trajectory of each layer of the part to fix the speed for melt deposition. Every time a layer is completed, the workbench is lowered by a layer thickness to superimpose and deposit a new layer, so that the deposition and molding of the parts are finally realized through repetition. The key to the FDM process is to keep the temperature of the semi-flow molding material just above the melting point (about 1°C higher than the melting point). FDM technology has the advantages of high material utilization rate, low material cost, and many types of optional materials, which is suitable for conceptual modeling and shape and function testing of products. Fused deposition modeling plays a vital role in the field of 3D printing. This is due to its relatively simple molding method, high molding precision, good hardness of the printed model, strong promotion, does not rely on laser as the molding energy, and the cost of printing equipment is low, so it has become the most popular 3D printing technology at present.

However, the commonly used FDM 3D printing thermoplastic materials such as PLA, ABS and PC are all printed at a temperature above 200°C, and the molding temperature is relatively high, and high temperature means high energy consumption and low safety, especially when used in a home environment. It will cause harm to children and other people with poor self-protection ability. More importantly, the higher processing temperature also limits the addition of various functional active substances to 3D printing materials, which greatly limits the development of functional materials. At the same time, these materials have poor biocompatibility and degradability, which limits the application of 3D printing in the biomedical field, and non-degradable materials are also likely to cause environmental pollution. For example, the patent publication number CN106928671A "A high-strength shape memory 3D printing bioplastic and its preparation method" develops a 3D printing consumable whose processing temperature and service temperature are above 180°C, which greatly limits the further development of its biological functionality. develop.

PCL is a linear aliphatic polyester that is semi-crystalline at room temperature and has a relatively low melting point (59-64°C). These basic properties endow it with good biocompatibility, flexibility, processability, and good biodegradability. These are good foundations for PCL to be used as a biofunctional degradable low-temperature FDM 3D printing material. However, as a 3D printing material, pure PCL has problems such as slow solidification, low melt strength, and difficult molding. As a result, there is currently no PCL material that can be used for FDM 3D printing. For example, the PCL/Hap composite material developed in Patent Publication No. CN106474566A "A 3D Printing PCL/Hap Composite Material and Its Preparation Method, Application, and Printing Method" has realized low-temperature 3D printing, but its material is slurry, which requires Only special 3D printers can be used, and the operation is complicated and difficult to implement, which greatly limits the promotion of low-temperature 3D printing materials.

Contents of the invention

The purpose of the present invention is to solve the problems existing in PCL FDM 3D printing, and to provide a composite material and preparation method that can degrade FDM biomedical 3D at low temperature. This method uses a natural degradable material - starch as a nucleation accelerator to promote the formation of PCL by promoting the crystallization of PCL to improve the 3D printing performance of the material while retaining the good biocompatibility and degradability of the material . In this method, the PCL masterbatch and the filler are melted and mixed by a twin-screw, crushed and granulated, extruded by a single-screw, and stretched into a 3D printing wire.

The technical scheme that the present invention adopts is as follows:

A low-temperature FDM type biomedical degradable 3D printing material, its raw material composition mass percentage includes as follows: polycaprolactone (PCL) masterbatch 80-90%, such as 80%, 82%, 84%, 86%, 88%, 90%, etc., starch 1-15%, such as 1%, 3%, 5%, 7%, 9%, 11%, 13%, 15%, etc., EBS 1-5%, such as 1%, 2% %, 3%, 4%, 5%, etc., SiO ₂ 1-5%, such as 1%, 2%, 3%, 4%, 5%, etc., magnesium stearate 1-5%, such as 1%, 2% %, 3%, 4%, 5%, etc., the sum of the mass percentages of the above five raw materials is ≤100%.

The starch is preferably one or more of potato starch, corn starch or soluble starch;

Further preferably, polycaprolactone (PCL) masterbatch 85-90%, potato starch 7-10% or corn starch 6-9% or soluble starch 9-11%, EBS 2-4%, SiO ₂ 2- 3%, magnesium stearate 2-5%. The sum of the mass percentages of the above five raw materials is ≤100%. Among them, if the filler concentration is too low, the material will be formed slowly, and the printing will not be easy to form. If the filler concentration is too high, the viscosity of the material will be too high, it will be difficult to pass through the tip of the nozzle, and the printing will not be smooth enough.

The method for preparing the above-mentioned low-temperature FDM type biomedical degradable 3D printing material is characterized in that it comprises the following steps:

(1) Weigh a certain amount of PCL masterbatch and starch (potato starch, corn starch and soluble starch, etc.), EBS (ethylene bisstearamide) and SiO ₂ , magnesium stearate, mix and stir it , to make it preliminarily mixed uniformly, and then use a twin-screw extruder to melt and blend under suitable conditions; after cooling, crush and granulate the prepared composite material;

(2) The pellets obtained in step (1) are melted and extruded in a single-screw extruder, and drawn by a tractor to form a wire rod with a suitable and uniform size.

Preferably, the processing temperature of the twin-screw extruder is 45-100° C., and the screw speed is 10-30 rpm.

Preferably, the processing temperature of the single-screw extruder is 65-90° C., and the screw speed is 20-50 rpm.

Preferably, the diameter of the wire is 1.65-1.75mm.

The application of low-temperature FDM 3D printing materials, as FDM 3D printer consumables, printing models and engineering components.

Composite material FDM type 3D printing condition range: nozzle temperature 80-90°C, base plate temperature 20-35°C, nozzle moving speed and wire feeding speed less than 40mm/s and 90mm/s respectively.

The low-temperature FDM 3D printing material of the present invention is used for 3D printing, and compared with previous literature reports, it has the following advantages:

(1) The present invention has successfully developed a composite material that can be 3D printed at low temperature (80-90°C). The material has low printing temperature, high precision and good printing performance.

(2) The preparation method of the present invention is simple and easy, the conditions are controllable, and the preparation cost is low.

(3) The low-temperature 3D printing consumables produced by the present invention have low requirements on 3D printing equipment and wide selectivity, and can also be used in general household FDM 3D printers.

(4) The main raw materials PCL and starch used in the present invention are all degradable materials, and the product is degradable without causing plastic pollution. And it has good biocompatibility and can be used for medical purposes.

Description of drawings

Fig. 1 is the low-temperature FDM type 3D printing wire material diagram prepared by the present invention;

Fig. 2 is a comparison chart of the printing effect of the low-temperature FDM type 3D printing wire prepared by the present invention compared with that of pure PCL.

detailed description

The present invention will be further described below in conjunction with the examples, but the present invention is not limited to the following examples.

Example 1

Weigh 80g of PCL masterbatch and place it in a 250mL beaker, then weigh and add 5g of corn starch, 5g of EBS, 5g of SiO ₂ and 5g of magnesium stearate. Use a mixer to mix it well.

Put the mixture in a twin-screw extruder, and fully blend the PCL and the filler by means of melt blending. Set the temperature of zone 1, zone 2, zone 3 and zone 4 of the twin-screw extruder to 50, 75, 100 and 75°C, respectively. Set the screw speed at 20 rpm. After the blending is completed, the prepared materials are pulverized and granulated.

The prepared pellets are melted and extruded by a single-screw extruder, and pulled by a tractor to form a wire with uniform size. Set the temperature of the first zone and the second zone of the single-screw extruder to 80°C and 85°C respectively, the screw speed to 30rpm, and the wire size to 1.70-1.75mm.

When printing with an FDM 3D printer, set the 3D printer parameters as follows: nozzle temperature 85°C, bottom plate temperature 35°C, nozzle moving speed and wire feeding speed 40mm/s and 90mm/s, respectively.

Example 2

Weigh 82g of PCL masterbatch and place it in a 250mL beaker, then weigh and add 8g of potato starch, 2g of EBS, 3g of SiO ₂ and 5g of magnesium stearate. Use a mixer to mix it well.

Put the mixture in a twin-screw extruder, and fully blend the PCL and the filler by means of melt blending. The temperatures of the first zone, the second zone, the third zone and the fourth zone of the twin-screw extruder were respectively set to 60, 75, 90 and 75°C. Set the screw speed at 20 rpm. After the blending is completed, the prepared materials are pulverized and granulated.

The prepared pellets are melted and extruded by a single-screw extruder, and pulled by a tractor to form a wire with uniform size. Set the temperature of the first zone and the second zone of the single-screw extruder to 80°C and 85°C respectively, the screw speed to 30rpm, and the wire size to 1.70-1.75mm.

When printing with an FDM 3D printer, set the 3D printer parameters as follows: nozzle temperature 85°C, bottom plate temperature 35°C, nozzle moving speed and wire feeding speed 40mm/s and 90mm/s, respectively.

Example 3

Weigh 84g of PCL masterbatch and place it in a 250mL beaker, then weigh and add 6g of soluble starch, 4g of EBS, 3g of SiO ₂ and 3g of magnesium stearate. Use a mixer to mix it well.

Put the mixture in a twin-screw extruder, and fully blend the PCL and the filler by means of melt blending. Set the temperature of zone 1, zone 2, zone 3 and zone 4 of the twin-screw extruder to 50, 70, 90 and 75°C, respectively. Set the screw speed at 15 rpm. After the blending is completed, the prepared materials are pulverized and granulated.

The prepared pellets are melted and extruded by a single-screw extruder, and pulled by a tractor to form a wire with uniform size. Set the temperature of the first zone and the second zone of the single-screw extruder to 80°C and 85°C respectively, the screw speed to 40rpm, and the diameter of the wire to be 1.70-1.75mm.

When printing with an FDM 3D printer, set the 3D printer parameters as follows: nozzle temperature 85°C, base plate temperature 20°C, nozzle moving speed and wire feeding speed 40mm/s and 90mm/s, respectively.

Example 4

Weigh 86g of PCL masterbatch and place it in a 250mL beaker, then weigh and add 4g of potato starch, 3g of EBS, 3g of SiO ₂ and 4g of magnesium stearate. Use a mixer to mix it well.

Put the mixture in a twin-screw extruder, and fully blend the PCL and the filler by means of melt blending. Set the temperature of zone 1, zone 2, zone 3 and zone 4 of the twin-screw extruder to 60, 70, 90 and 75°C, respectively. Set the screw speed at 20 rpm. After the blending is completed, the prepared materials are pulverized and granulated.

The prepared pellets are melted and extruded by a single-screw extruder, and pulled by a tractor to form a wire with uniform size. Set the temperature of the first zone and the second zone of the single-screw extruder to 70 and 75° C., the screw speed to 30 rpm, and the wire size to 1.70-1.75 mm.

When printing with an FDM 3D printer, set the 3D printer parameters as follows: nozzle temperature 85°C, bottom plate temperature 35°C, nozzle moving speed and wire feeding speed 40mm/s and 90mm/s, respectively.

Example 5

Weigh 88g of PCL masterbatch and place it in a 250mL beaker, then weigh and add 9g of soluble starch, 1g of EBS, 1g of SiO ₂ and 1g of magnesium stearate. Use a mixer to mix it well.

Put the mixture in a twin-screw extruder, and fully blend the PCL and the filler by means of melt blending. The temperatures of zone 1, zone 2, zone 3 and zone 4 of the twin-screw extruder were respectively set at 55, 75, 90 and 75°C. Set the screw speed at 25 rpm. After the blending is completed, the prepared materials are pulverized and granulated.

The prepared pellets are melted and extruded by a single-screw extruder, and pulled by a tractor to form a wire with uniform size. Set the temperature of the first zone and the second zone of the single-screw extruder to 80°C and 85°C respectively, the screw speed to 30rpm, and the wire size to 1.70-1.75mm.

When printing with an FDM 3D printer, set the 3D printer parameters as follows: nozzle temperature 85°C, base plate temperature 25°C, nozzle moving speed and wire feeding speed 30mm/s and 60mm/s, respectively.

Example 6

Weigh 90g of PCL masterbatch and place it in a 250mL beaker, then weigh and add 5g of corn starch, 3g of EBS, 1g of SiO ₂ and 1g of magnesium stearate. Use a mixer to mix it well.

Put the mixture in a twin-screw extruder, and fully blend the PCL and the filler by means of melt blending. The temperatures of zone 1, zone 2, zone 3 and zone 4 of the twin-screw extruder were respectively set at 55, 75, 85 and 75°C. Set the screw speed at 20 rpm. After the blending is completed, the prepared materials are pulverized and granulated.

The prepared pellets are melted and extruded by a single-screw extruder, and pulled by a tractor to form a wire with uniform size. Set the temperature of the first zone and the second zone of the single-screw extruder to 70 and 75° C., the screw speed to 40 rpm, and the wire size to 1.70-1.75 mm.

When printing with an FDM 3D printer, set the 3D printer parameters as follows: nozzle temperature 90°C, base plate temperature 20°C, nozzle moving speed and wire feeding speed 20mm/s and 40mm/s, respectively.

The low-temperature FDM 3D printing wire prepared by the above implementation can be seen in Figure 1; the printing effect of the low-temperature FDM 3D printing wire prepared in the embodiment of the present invention and the printing effect of pure PCL are shown in Figure 2.

Claims (9)

1. a kind of low temperature FDM types biological medical degradable 3D printing material, it is characterised in that its raw material forms weight/mass percentage composition Including as follows：Polycaprolactone (PCL) master batch 80-90%, starch 1-15%, EBS 1-5%, SiO₂1-5%, magnesium stearate 1- 5%, mass percent sum≤100% of above-mentioned five kinds of raw materials.

2. according to a kind of low temperature FDM types biological medical degradable 3D printing material described in claim 1, it is characterised in that poly- Caprolactone (PCL) master batch 85-90%, farina 7-10% or cornstarch 6-9% or soluble starch 9-11%, EBS 2-4%, SiO₂2-3%, magnesium stearate 2-5%.

3. according to a kind of low temperature FDM types biological medical degradable 3D printing material described in claim 1 or 2, it is characterised in that Starch is the one or more in farina, cornstarch or soluble starch.

4. according to a kind of low temperature FDM types biological medical degradable 3D printing material described in claim 1 or 2, it is characterised in that Gauge or diameter of wire size is 1.65-1.75mm.

5. the preparation method of the low temperature FDM type biological medical degradable 3D printing materials described in claim any one of 1-4, it is special Sign is, comprises the following steps：

(1) a certain amount of PCL master batches and starch and SiO are weighed₂, magnesium stearate, after mixing, it is stirred, it is tentatively mixed Uniformly, double screw extruder melt blending under suitable conditions is reused；After cooling, obtained composite is crushed and is granulated；

(2) by pellet melting extrusion in single screw extrusion machine obtained by step (1), by the traction of hauling machine, form size and close Suitable homogeneous wire rod.

6. according to the method for claim 5, it is characterised in that double screw extruder processing temperature is 45-100 DEG C, screw speed For 10-30rpm.

7. according to the method for claim 5, it is characterised in that single screw extrusion machine processing temperature is 65-90 DEG C, and screw speed is 20-50rpm。

8. the application of the low temperature FDM type biological medical degradable 3D printing materials described in claim any one of 1-4, its feature exist In, as FDM type 3D printer consumptive materials, printer model and engineering element.

9. the application of the low temperature FDM type biological medical degradable 3D printing materials described in claim any one of 1-4, its feature exist In print conditions scope：80-90 DEG C of nozzle temperature, 20-35 DEG C of baseplate temp, spout translational speed and to enter thread speed difference small In 40mm/s, 90mm/s.