阅读说明：本技术 一种3d打印用pla/tpu双组份线材及其制备方法 (PLA/TPU (polylactic acid/thermoplastic polyurethane) double-component wire for 3D printing and preparation method thereof ) 是由 刘志鹏 陈作珍 于 2019-05-05 设计创作，主要内容包括：本发明提供一种3D打印用PLA/TPU双组份线材及其制备方法。采用自主开发3D线材挤出生产线制备“皮－芯”结构3D线材,皮层为PLA材料,芯层为适量的羟基磷灰石与聚酯型TPU的共混物,PLA/TPU双组份按一定配比分别置于A挤出螺杆和B挤出螺杆中,A挤出螺杆加工温度Ⅰ～Ⅵ区(℃)：195～200,185～190,190～195,190～195,190～195,185～190,B挤出螺杆加工温度Ⅰ～Ⅵ区(℃)：190～195,200～205,200～205,205～210,205～210,200～205,通过适量的羟基磷灰石和聚酯型TPU,改善PLA与TPU两相间的粘结力,经特制模头共挤制备PLA/TPU双组份线材。本发明有益效果是：本发明不仅克服了PLA线材脆性高和抗冲击性能差的缺陷,而且克服了TPU材料收卷易粘连和难打印的缺陷,适用于3D打印,富有弹性,易打印,可用于关节连接处打印。(The invention provides a PLA/TPU double-component wire for 3D printing and a preparation method thereof. The method is characterized in that a 3D wire with a skin-core structure is prepared by adopting an independently developed 3D wire extrusion production line, the skin layer is made of PLA material, the core layer is made of a blend of hydroxyapatite and polyester TPU, the PLA/TPU double components are respectively arranged in an extrusion screw A and an extrusion screw B according to a certain proportion, and the processing temperature of the extrusion screw A is in a range from I to VI (DEG C): 195 ~ 200, 185 ~ 190, 190 ~ 195, 190 ~ 195, 190 ~ 195, 185 ~ 190, B extrude screw rod processing temperature I ~ VI district (deg.C): 190-195, 200-205, 205-210, 200-205, improving the bonding force between two phases of PLA and TPU through a proper amount of hydroxyapatite and polyester TPU, and co-extruding the two phases of PLA/TPU through a special die head to prepare the PLA/TPU double-component wire. The invention has the beneficial effects that: the invention not only overcomes the defects of high brittleness and poor impact resistance of PLA wires, but also overcomes the defects of easy adhesion and difficult printing when the TPU material is rolled, is suitable for 3D printing, has high elasticity, is easy to print, and can be used for printing at joint joints.)

1. A PLA/TPU double-component wire for 3D printing and a preparation method thereof are characterized by comprising the following specific steps: the 3D wire extrusion production line is used for preparing a 3D wire with a skin-core structure, the skin layer is made of PLA material, the core layer is a blend of hydroxyapatite and polyester TPU, the PLA/TPU double components are respectively arranged in an extrusion screw A and an extrusion screw B according to a certain proportion, and the processing temperature of the extrusion screw A is in a range from I to VI (DEG C): 195 ~ 200, 185 ~ 190, 190 ~ 195, 190 ~ 195, 190 ~ 195, 185 ~ 190, B extrude screw rod processing temperature I ~ VI district (deg.C): 190-195, 200-205, 205-210, 200-205, co-extruding PLA/TPU double-component wire rods through a special die head.

2. The PLA/TPU bi-component wire for 3D printing and the preparation method thereof according to claim 1 are characterized in that: the wire structure is a skin-core concentric circle.

3. The PLA/TPU bi-component wire for 3D printing and the preparation method thereof according to claim 1 are characterized in that; the proportion of the components of the skin layer/the core layer is 0-50%: 50 to 100 percent.

4. The PLA/TPU bi-component wire for 3D printing and the preparation method thereof according to claim 1 are characterized in that: the content of the hydroxyapatite is 0.5 to 2 percent.

5. The PLA/TPU bi-component wire for 3D printing and the preparation method thereof according to claim 1 are characterized in that: the PLA material has a melt flow rate (190 ℃ and 2.16kg) of 6.0g/10 min-25 g/10min and a processing temperature of 180-200 ℃.

6. The PLA/TPU bi-component wire for 3D printing and the preparation method thereof according to claim 1 are characterized in that: the TPU material is polyester TPU, and the processing temperature is 190-210 ℃.

7. The PLA/TPU bi-component wire for 3D printing and the preparation method thereof according to claim 1 are characterized in that: the method comprises the steps of cooling PLA/TPU wires extruded from a die orifice of an extruder by cooling water at 7-15 ℃, and drying by an air-cooled conveyor belt to obtain extruded wires suitable for 3D printing size requirements.

8. The PLA/TPU bi-component wire for 3D printing and the preparation method thereof according to claim 1 are characterized in that: the method comprises the steps of collecting the water-cooled and dried extruded wires by using a wire coiling machine through a wire coil, wherein the coiling frequency is controlled to be 5-20 HZ.

Technical Field

The invention relates to the technical field of 3D printing manufacturing, in particular to a PLA/TPU double-component wire for 3D printing and a preparation method thereof.

Background

The 3D printing technology, i.e. additive manufacturing technology, is an emerging rapid prototyping technology. The method is a technology for constructing an object by using a bondable material such as powder metal or plastic and the like in a layer-by-layer printing mode on the basis of a digital model file, does not need to manufacture a die, and saves the time and the cost for manufacturing the die. The basic principle is laminate manufacturing, a technique of adding material layer by layer to create a three-dimensional entity. As a core technology for promoting the third industrial revolution, 3D printing has the characteristics of networking, digitalization, individualization, and the like, and is gradually applied to the fields of medicine, bioengineering, construction, clothing, aviation, and the like.

The Fused Deposition Modeling (FDM) technique is generally used for printing on a desktop, and because of its simple operation, the material is generally available, and becomes a common technique in the 3D printing technique. The principle is that a thermoplastic polymer material is extruded from a nozzle in a molten state, is solidified to form a thin layer with a profile shape, and is stacked layer by layer to finally form a product. The used materials are mainly environment-friendly high polymer materials, such as: PLA, ABS, PCL, PHA, PBS, etc. In order to avoid the safety problem caused by the contact of the odor generated by the melted polymer material or harmful substances generated by decomposition with people, polylactic acid (PLA) in the materials is the most widely applied polymer material in FDM technology because of the sufficient and renewable raw material sources, biodegradability and biocompatibility. However, since the glass transition temperature of PLA is high, PLA has a hard and brittle nature at room temperature, and is difficult to be applied to joint printing, thereby severely limiting its application in the field of 3D printing.

Thermoplastic polyurethane elastomer (TPU) has good flexibility, and 3D consumable developers continuously try to extrude the consumables from TPU materials, but the problems that TPU wires are easy to adhere during winding, the feeding is difficult during 3D printing, the printing efficiency is low and the like are solved, so that the problem becomes the main reason for limiting the application of the TPU to the field of 3D printing.

The soft segment of the TPU is predominantly polyester or polyether, and PLA has been found to be compatible with some polyesters or polyethers, so TPU has good compatibility with PLA; more urethane linkages in the hard segment portion of the TPU may form hydrogen bonding interactions with the PLA, thereby enhancing the bond between the two phases. The appropriate amount of hydroxyapatite is added into a system to be used as a PLA/TPU interface modifier, the hydroxyapatite and the PLA have good bonding strength through interaction, and hydrogen bonds are formed between the hydroxyapatite and the TPU, so that the interfacial adhesion between two phases of the PLA and the TPU are improved through the hydroxyapatite, the PLA is coated on the surface layer of the TPU, the defects that a TPU wire rod is easy to adhere when being rolled and is difficult to print are overcome, the PLA/TPU wire rod is endowed with high flexibility, and the PLA/TPU wire rod can be used for printing at a joint and expanding the application range of the PLA/TPU wire rod.

Disclosure of Invention

Based on the background and problems, the invention aims to provide a PLA/TPU wire which has good flexibility and is easy to print and a preparation method thereof.

In order to achieve the above purpose, the solution of the invention is:

a PLA/TPU double-component wire for 3D printing and a preparation method thereof are disclosed, which comprises the following steps: the 3D wire extrusion production line is used for preparing a 3D wire with a skin-core structure, the skin layer is made of PLA material, the core layer is a blend of hydroxyapatite and polyester TPU, the PLA/TPU double components are respectively arranged in an extrusion screw A and an extrusion screw B according to a certain proportion, and the processing temperature of the extrusion screw A is in a range from I to VI (DEG C): 195 ~ 200, 185 ~ 190, 190 ~ 195, 190 ~ 195, 190 ~ 195, 185 ~ 190, B extrude screw rod processing temperature I ~ VI district (deg.C): 190-195, 200-205, 205-210, 200-205, co-extruding PLA/TPU double-component wire rods through a special die head.

The PLA/TPU wire structure: "skin-core" concentric circles;

the proportion of the components of the skin layer/the core layer is as follows: 0-50%: 50-100%;

the content of the hydroxyapatite is as follows: 0.5 to 2 percent.

Melt flow rate of the PLA material (210 ℃, 2.16 kg): 6.0g/10 min-25 g/10min, and the processing temperature is 180-200 ℃.

The TPU material is polyester TPU, and the processing temperature is 190-210 ℃.

The preparation method comprises the following steps: and cooling the PLA/TPU wire rods extruded from the die orifice of the extruder by cooling water at 7-15 ℃, and drying by using an air-cooled conveyor belt to obtain the extruded wire rods suitable for the 3D printing size requirement.

The preparation method comprises the following steps: and collecting the water-cooled and dried extruded wires by using a wire coiling machine through a wire coil, wherein the coiling frequency is controlled to be 5-20 HZ.

The invention has the beneficial effects that:

1. the PLA/TPU double-component wire rod has the characteristics that the PLA is covered on the TPU surface layer, the coiling is not sticky, the printing is easy, and the like;

2. by properly adding hydroxyapatite and polyester TPU, better bonding between TPU and PLA phases is realized, and the printed product has high quality and excellent performance;

3. the processing temperature of the screened PLA and TPU is similar, the melting points are close, and the wire forming and wire printing are realized by utilizing the PLA and the TPU.

Detailed Description

The following are several specific examples of the present invention to further illustrate the present invention, but the present invention is not limited thereto.