阅读说明：本技术 一种聚乳酸聚羟基脂肪酸酯熔喷非织造材料的制备方法 (Preparation method of polylactic acid polyhydroxyalkanoate melt-blown nonwoven material ) 是由 江科 于 2021-10-26 设计创作，主要内容包括：本发明公开了一种聚乳酸聚羟基脂肪酸酯熔喷非织造材料的制备方法,涉及非织造新材料技术领域,通过添加聚羟基脂肪酸酯与聚乳酸共混,在提高熔喷非织造材料的熔融指数的同时,提高熔喷非织造材料中的增韧效果,在保证拉伸强度变化不大下,改善熔喷非织造材料的韧性,提高熔喷非织造材料的断裂伸长率,既具备环境友好、可生物降解的性能,同时又具有较好的力学性能,为材料的后续开发和广泛应用提供了可能,而微型步进电机的动力驱动端连接有螺杆,螺杆的外部自下而上分别螺纹连接有下盖板和上盖板,通过微型步进电机带动螺杆正向和反向传动的方式,可达到对原材料分量下料的效果,提高了用量的精准性、使用的便捷性和实用性。(The invention discloses a preparation method of a melt-blown nonwoven material of polylactic acid polyhydroxyalkanoate, which relates to the technical field of new nonwoven materials, wherein polyhydroxyalkanoate and polylactic acid are added for blending, the melt index of the melt-blown nonwoven material is improved, the toughening effect in the melt-blown nonwoven material is improved, the toughness of the melt-blown nonwoven material is improved and the breaking elongation of the melt-blown nonwoven material is improved under the condition of ensuring that the tensile strength is not changed greatly, the melt-blown nonwoven material has the environment-friendly and biodegradable properties and better mechanical properties, the possibility is provided for the subsequent development and wide application of the material, the power driving end of a micro stepping motor is connected with a screw, the outer part of the screw is respectively in threaded connection with a lower cover plate and an upper cover plate from bottom to top, and the effect of component blanking of the raw materials can be achieved by driving the screw to positively and reversely drive the screw through the micro stepping motor, the accuracy of quantity, the convenience and the practicality of use have been improved.)

1. A preparation method of a polylactic acid polyhydroxyalkanoate melt-blown nonwoven material is characterized by comprising the following steps:

s1, respectively putting the prepared melt-blown non-woven raw materials into a component feeding mechanism (9), and then feeding the components into the mixing barrel (4) through a first component assembly (95) and a second component assembly (96);

s2, starting a driving motor (5), and driving a stirring blade (8) to rotate and stir at a high speed under the action of a belt pulley group (6) and a driving rod (7) until the materials are uniformly mixed;

s3, after mixing, carrying out melt extrusion granulation through a screw extruder, wherein the temperature of the screw extruder is 160-175 ℃;

s4, preparing the polylactic acid polyhydroxyalkanoate melt-blown non-woven material by a melt-blown process, wherein the melt-blown spinning temperature is 190 ℃ and 210 ℃, the melt-extrusion speed is 10-30Hz, the side air speed is 0.06-0.12 Mpa, the receiving distance is 20-30cm, and the mesh belt speed is 4-8 Hz;

the material feeding mechanism (9) comprises a hopper (91), the interior of the hopper (91) is divided into two spaces of a first chamber (93) and a second chamber (94) through a partition plate (92), and the edges of the first chamber (93) and the second chamber (94) are respectively provided with a first component assembly (95) and a second component assembly (96) which are identical and symmetrical in structure;

first subassembly (95) include material section of thick bamboo (951), buckler (952) and miniature step motor (953), the power drive end of miniature step motor (953) is connected with screw rod (954), the outside threaded connection respectively has lower apron (955) and upper cover plate (956) from bottom to top of screw rod (954), lower apron (955) and upper cover plate (956) are located material section of thick bamboo (951) under and directly over respectively.

2. The method for preparing the polylactic acid polyhydroxyalkanoate melt-blown nonwoven material of claim 1, wherein a sliding column (958) is connected to the outer side of the material cylinder (951) through a connecting plate (957), the lower cover plate (955) and the upper cover plate (956) are both sleeved on the outer side of the sliding column (958), and the micro stepping motor (953) is positioned inside the waterproof cover (952).

3. The method for preparing a melt-blown nonwoven material of polylactic acid polyhydroxyalkanoate according to claim 1, wherein a second waterproof bearing (9510) is arranged at the joint of the screw rod (954) and the waterproof cover (952), and a sealing gasket (959) is adhered to the adjacent end surfaces of the lower cover plate (955) and the upper cover plate (956).

4. The method for preparing a melt-blown nonwoven material of polyhydroxyalkanoate according to claim 1, wherein a moving seat (1) is disposed below the mixing tub (4) in step S1, a first support (2) and a second support (3) are respectively mounted at two ends of the top of the moving seat (1), a driving motor (5) is mounted at the top of the first support (2), and the mixing tub (4) is mounted at the upper end of the second support (3).

5. The preparation method of the polylactic acid polyhydroxyalkanoate melt-blown nonwoven material according to claim 4, wherein a power driving end of the driving motor (5) is connected with a pulley group (6), an output end of the pulley group (6) is connected with a driving rod (7), the top of the driving rod (7) extends into the mixing barrel (4) and is provided with a stirring blade (8), the surface of the stirring blade (8) is provided with a plurality of through holes (10), and a first waterproof bearing (11) is arranged at the joint of the driving rod (7) and the mixing barrel (4).

6. The preparation method of the polylactic acid polyhydroxyalkanoate melt-blown nonwoven material according to claim 4, wherein a discharge pipe (12) communicated with the bottom of the mixing barrel (4) is installed on one side of the bottom of the mixing barrel (4), a valve (13) and a support plate (14) are respectively sleeved outside the discharge pipe (12), and the top of the support plate (14) is connected with the second support (3).

7. The method of claim 1, wherein the melt-blown nonwoven raw material obtained in step S1 comprises the following components: 80.0-99.0 parts of polylactic acid, 1.0-20.0 parts of polyhydroxyalkanoate and 0.1-0.5 part of plasticizer.

8. The method for preparing the polylactic acid-polyhydroxyalkanoate melt-blown nonwoven material of claim 7, wherein the polylactic acid is one or more of a dextro-polylactic acid, a levo-polylactic acid, a racemic polylactic acid and a polylactic acid stereocomplex.

9. The method of claim 7, wherein the polyhydroxyalkanoate is poly (3-hydroxybutyrate-co-4-hydroxybutyrate) P34HB, the 4-hydroxybutyrate content is 10-20mol%, and the plasticizer is monoglyceride or epoxidized soybean oil.

Technical Field

The invention relates to the technical field of new nonwoven materials, in particular to a preparation method of a polylactic acid polyhydroxyalkanoate melt-blown nonwoven material.

Background

Melt-blown nonwoven technology is becoming an important means for providing novel fiber materials, is a branch of emerging material industry, and is being gradually applied in the fields of aerospace, environmental protection, agriculture, medical care, daily life of people and the like. The new non-woven material has become an increasingly important product and is widely applied to the fields of filter materials, oil absorption materials, sound insulation materials, medical sanitary materials, industrial and household wiping materials, thermal insulation materials and the like. With the rapid development of modern construction of each industrial department in China, the three wastes treatment and environmental pollution prevention and control are more and more important in China, the environment-friendly industry is a very large market, and the non-woven material has wide prospects no matter now or in the future.

Polylactic acid is a completely biodegradable aliphatic polyester material prepared by taking renewable plant resources as raw materials through chemical synthesis, has good mechanical strength, biocompatibility, absorbability and environmental degradability, is the only transparent biodegradable high polymer material at present, can be applied to the field of transparent materials, but has defects, particularly brittleness in the aspect of mechanical property, and limits the development and application of the polylactic acid melt-blown material.

Polyhydroxyalkanoate (PHA) is another biodegradable plastic, has good blending property with PLA, can effectively improve the toughness of PLA materials, and is one of the methods for improving the mechanical property of PLA. Commonly used PHAs include Polyhydroxybutyrate (PHB), poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), poly (3-hydroxybutyrate-co-4-hydroxybutyrate) (P34 HB), etc., but both PHB and PHBV have higher crystallinity and do not improve the toughness of PLA much; and P34HB shows the transition from rigidity to toughness with the introduction of 4 HB.

At present, the polylactic acid resin realizes the regulation and control of melt index, molecular weight and molecular weight distribution mainly by controlling the proportion of lactide and an initiator in polymerization reaction, the method is limited by factors such as a catalytic system, reaction conditions and the like, the stability of high melt index is difficult to control, in the fields of melt-blown spinning and high-speed spinning non-woven fabrics, the polylactic acid resin with ultrahigh melt index, which requires melt index of more than 100g/10min and stable flow property, has not been reported, if melt-blown non-woven materials are prepared by simply improving the melt index of polylactic acid, the problems of poor mechanical property and even incapability of normal use of the materials are faced, in recent years, the preparation of polylactic acid non-woven products, particularly the toughening and modification research of the polylactic acid products is more, but most of the polylactic acid toughening products are mainly applied to the fields of spun bond, hot rolling and spunlace non-woven fabrics, there has been little research and manufacturing on melt blown nonwoven materials, and for this reason, workers in the art have proposed a method for preparing melt blown nonwoven materials of polylactic acid polyhydroxyalkanoates.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a preparation method of a polylactic acid polyhydroxyalkanoate melt-blown non-woven material, which solves the problems that the existing melt-blown non-woven material has poor toughness and can not be completely biodegraded.

In order to achieve the purpose, the invention is realized by the following technical scheme: a method for preparing a polylactic acid polyhydroxyalkanoate melt-blown nonwoven material comprises the following steps:

s1, respectively putting the prepared melt-blown non-woven raw materials into a component feeding mechanism, and then feeding the components into the mixing barrel through a first component assembly and a second component assembly;

s2, starting a driving motor, and driving stirring blades to rotate and stir at a high speed under the action of a belt pulley set and a driving rod until the stirring blades are uniformly mixed;

s3, after mixing, carrying out melt extrusion granulation through a screw extruder, wherein the temperature of the screw extruder is 160-175 ℃;

s4, preparing the polylactic acid polyhydroxyalkanoate melt-blown non-woven material by a melt-blown process, wherein the melt-blown spinning temperature is 190 ℃ and 210 ℃, the melt-extrusion speed is 10-30Hz, the side air speed is 0.06-0.12 Mpa, the receiving distance is 20-30cm, and the mesh belt speed is 4-8 Hz;

the component feeding mechanism in the step S1 includes a hopper, the inside of the hopper is divided into two spaces, namely a first chamber and a second chamber, by a partition plate, and the edges of the first chamber and the second chamber are respectively provided with a first component assembly and a second component assembly which have the same structure and are symmetrical;

the first component assembly comprises a material cylinder, a waterproof cover and a micro stepping motor, a power driving end of the micro stepping motor is connected with a screw, the outside of the screw is respectively in threaded connection with a lower cover plate and an upper cover plate from bottom to top, and the lower cover plate and the upper cover plate are respectively positioned right below and right above the material cylinder.

As a further technical scheme, the outer side of the material barrel is connected with a sliding column through a connecting plate, the lower cover plate and the upper cover plate are sleeved outside the sliding column, and the micro stepping motor is located inside the waterproof cover.

As a further technical scheme of the invention, a second waterproof bearing is arranged at the joint of the screw and the waterproof cover, and sealing gaskets are adhered to the adjacent end surfaces of the lower cover plate and the upper cover plate.

As a further technical solution of the present invention, a moving seat is disposed below the mixing tub in step S1, a first bracket and a second bracket are respectively mounted at two ends of the top of the moving seat, a driving motor is mounted at the top of the first bracket, and the mixing tub is mounted at the upper end of the second bracket.

As a further technical scheme, a power driving end of the driving motor is connected with a belt pulley group, an output end of the belt pulley group is connected with a driving rod, the top of the driving rod extends into the mixing barrel and is provided with a stirring blade, the surface of the stirring blade is provided with a plurality of through holes, and a first waterproof bearing is arranged at the joint of the driving rod and the mixing barrel.

As a further technical scheme, one side of the bottom of the mixing barrel is provided with a communicated discharge pipe, the exterior of the discharge pipe is respectively sleeved with a valve and a bearing plate, and the top of the bearing plate is connected with a second support.

As a further technical solution of the present invention, the melt-blown nonwoven raw material in step S1 includes the following components: 80.0-99.0 parts of polylactic acid, 1.0-20.0 parts of polyhydroxyalkanoate and 0.1-0.5 part of plasticizer.

As a further technical scheme of the invention, the polylactic acid is one or more of dextrorotatory polylactic acid, levorotatory polylactic acid, racemic polylactic acid and a polylactic acid stereo complex.

As a further technical scheme, the polyhydroxy fatty acid ester is poly (3-hydroxybutyrate-co-4-hydroxybutyrate) P34HB, wherein the content of 4-hydroxybutyrate is 10-20mol%, and the plasticizer is monoglyceride or epoxidized soybean oil.

Advantageous effects

The invention provides a preparation method of a polylactic acid polyhydroxyalkanoate melt-blown nonwoven material. Compared with the prior art, the method has the following beneficial effects:

1. a preparation method of a polylactic acid polyhydroxyalkanoate melt-blown non-woven material is characterized in that polyhydroxyalkanoate and polylactic acid are added for blending, the melt index of the melt-blown non-woven material is improved, the toughening effect in the melt-blown non-woven material is improved, the toughness of the melt-blown non-woven material is improved under the condition that the tensile strength is not changed greatly, the breaking elongation of the melt-blown non-woven material is improved, the environment-friendly and biodegradable performance is achieved, the mechanical property is good, the possibility is provided for the subsequent development and wide application of the material, in addition, the raw materials are low in relative price, the preparation method is simple, and the operation is easy.

2. The utility model provides a polylactic acid polyhydroxyalkanoate melts and spouts preparation method of nonwoven material, the inside of hopper is divided into two spaces of first cavity and second cavity respectively through the baffle, and the edge of first cavity and second cavity is provided with the same and symmetrical first component subassembly of structure and second component subassembly respectively, compares with the mode that multiple material was unified to be poured into in the past and is mixed, and this structure can be separated raw and other materials, and the ration is added many times for the mixing speed has improved mixing efficiency.

3. The utility model provides a polylactic acid polyhydroxyalkanoate melts preparation method of spouting non-woven material, through miniature step motor corotation, under the effect of screw rod, can make the lower cover plate close, the upper cover plate is opened, thereby be convenient for raw and other materials ration enter into in the material section of thick bamboo, the accuracy nature of quantity has been improved, and miniature step motor reversal, can make the lower cover plate open, the upper cover plate is closed, thereby can pour the raw and other materials in the material section of thick bamboo into to the blending tank, this structural design is small and exquisite, simple easy operation, can reach the effect to raw and other materials weight unloading, the convenience and the practicality of use have been improved.

Drawings

FIG. 1 is a schematic structural diagram of a method for preparing a polylactic acid polyhydroxyalkanoate meltblown nonwoven material;

FIG. 2 is a top view of a polylactic acid polyhydroxyalkanoate meltblown nonwoven material making process;

FIG. 3 is a cross-sectional view A-A of FIG. 2;

FIG. 4 is a schematic structural diagram of a material feeding mechanism of a method for preparing a polylactic acid polyhydroxyalkanoate melt-blown nonwoven material;

FIG. 5 is a schematic diagram of a first component assembly of a method of making a polylactic acid polyhydroxyalkanoate meltblown nonwoven material;

FIG. 6 is a top view of a first component assembly of a method of making a polylactic acid polyhydroxyalkanoate meltblown nonwoven material;

fig. 7 is a cross-sectional view of B-B in fig. 6.

In the figure: 1. a movable seat; 2. a first bracket; 3. a second bracket; 4. a mixing barrel; 5. a drive motor; 6. a pulley set; 7. a drive rod; 8. stirring blades; 9. a material feeding mechanism with a material weight; 91. a hopper; 92. a partition plate; 93. a first chamber; 94. a second chamber; 95. a first component assembly; 951. a material cylinder; 952. a waterproof cover; 953. a micro stepper motor; 954. a screw; 955. a lower cover plate; 956. an upper cover plate; 957. a connecting plate; 958. a traveler; 959. a gasket; 9510. a second waterproof bearing; 96. a second component assembly; 10. a through hole; 11. a first waterproof bearing; 12. a discharge pipe; 13. a valve; 14. a bearing plate.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-4, the present invention provides a method for preparing a melt-blown nonwoven material of polylactic acid polyhydroxyalkanoate, which comprises the following steps: a method for preparing a polylactic acid polyhydroxyalkanoate melt-blown nonwoven material comprises the following steps:

s1, the melt-blown nonwoven raw material prepared in advance is respectively put into the component feeding mechanism 9, and then fed in component into the mixing tub 4 through the first component feeding unit 95 and the second component feeding unit 96.

S2, starting the driving motor 5, and under the action of the pulley group 6 and the driving rod 7, driving the stirring blade 8 to rotate at high speed for stirring until the mixture is uniform.

S3, after the mixing is finished, carrying out melt extrusion granulation through a screw extruder, wherein the temperature of the screw extruder is 160-175 ℃.

S4, preparing the polylactic acid polyhydroxyalkanoate melt-blown non-woven material by a melt-blown process, wherein the melt-blown spinning temperature is 190-210 ℃, the melt extrusion speed is 10-30Hz, the side air speed is 0.06-0.12 Mpa, the receiving distance is 20-30cm, the mesh belt speed is 4-8Hz, the diameter of a single spinneret orifice is 0.2-0.3mm in the production process of the melt-blown process, the aperture is small, the processing temperature of the polylactic acid and the polyhydroxyalkanoate is similar, the polylactic acid and the polyhydroxyalkanoate can play a mutual plasticizing role, the spinneret orifice cannot be blocked, the production difficulty is reduced, and the polylactic acid/polyhydroxyalkanoate non-woven material with uniform fiber web, excellent mechanical property and proper gram weight can be prepared under the process condition.

The polylactic acid is one or more of dextrorotatory polylactic acid, levorotatory polylactic acid, racemic polylactic acid and polylactic acid stereo complex, the polyhydroxy fatty acid ester is poly (3-hydroxybutyrate-co-4-hydroxybutyrate) P34HB, the content of 4-hydroxybutyrate is 10-20mol%, the plasticizer is monoglyceride or epoxidized soybean oil, the polylactic acid and the polyhydroxy fatty acid ester have good miscibility, and the poly (3-hydroxybutyrate-co-4-hydroxybutyrate) P34HB has good toughening effect by adding a small amount of the polylactic acid and the polyhydroxy fatty acid ester, so that the breaking elongation of the melt-blown non-woven material is remarkably improved under the condition of small change of tensile strength, the flexibility of the melt-blown non-woven material is effectively improved, the brittleness of the melt-blown non-woven material is reduced, and the possibility is provided for subsequent development and wide application of the material.

In step S1, the melt blown nonwoven raw material comprises the following components: 80.0-99.0 parts of polylactic acid, 1.0-20.0 parts of polyhydroxyalkanoate and 0.1-0.5 part of plasticizer, all the used raw materials can be completely biodegraded, the environment is protected, the raw materials are relatively low in price, the preparation method is simple, and the operation is easy.

The lower part of the mixing barrel 4 in the step S1 is provided with a movable seat 1, a first support 2 and a second support 3 are respectively installed at two ends of the top of the movable seat 1, a driving motor 5 is installed at the top of the first support 2, the mixing barrel 4 is installed at the upper end of the second support 3, a power driving end of the driving motor 5 is connected with a belt pulley group 6, an output end of the belt pulley group 6 is connected with a driving rod 7, the top of the driving rod 7 extends to the inside of the mixing barrel 4 and is provided with a stirring blade 8, a plurality of through holes 10 are formed in the surface of the stirring blade 8, a first waterproof bearing 11 is installed at the joint of the driving rod 7 and the mixing barrel 4, a discharge pipe 12 communicated with each other is installed at one side of the bottom of the mixing barrel 4, a valve 13 and a supporting plate 14 are respectively sleeved outside the discharge pipe 12, and the top of the supporting plate 14 is connected with the second support 3.

Referring to fig. 4, the material feeding mechanism 9 in step S1 includes a hopper 91, the hopper 91 is divided into two spaces, namely a first chamber 93 and a second chamber 94, by a partition 92, and the edges of the first chamber 93 and the second chamber 94 are respectively provided with a first component assembly 95 and a second component assembly 96 which are identical and symmetrical in structure, so that the raw materials can be separated under the action of the first chamber 93 and the second chamber 94, thereby facilitating multiple quantitative feeding, increasing the mixing speed, and improving the mixing efficiency.

Referring to fig. 5-7, the first component assembly 95 includes a material cylinder 951, a waterproof cover 952 and a micro-stepper motor 953, a screw 954 is connected to a power driving end of the micro-stepper motor 953, a lower cover 955 and an upper cover 956 are respectively screwed to the outside of the screw 954 from bottom to top, the lower cover 955 and the upper cover 956 are respectively located right below and above the material cylinder 951, a sliding column 958 is connected to the outside of the material cylinder 951 through a connecting plate 957, the lower cover 955 and the upper cover 956 are both sleeved on the outside of the sliding column 958, the micro-stepper motor 953 is located inside the waterproof cover 952, a second waterproof bearing 9510 is provided at the joint of the screw 954 and the waterproof cover 952, a gasket 959 is adhered to the adjacent end surfaces of the lower cover 955 and the upper cover 956, the micro-stepper motor 953 rotates forward, the lower cover 955 is urged to close and the upper cover 956 is opened under the action of the screw 954, so that the raw material can be quantitatively fed into the material cylinder 951, the accuracy of quantity has been improved, and miniature step motor 953 reverses, can make down apron 955 and open, and upper cover plate 956 closes to can pour the raw and other materials in the material cylinder 951 into to mixing drum 4, this structural design is small and exquisite, and simple easy operation can reach the effect to raw and other materials weight unloading, has improved convenience and the practicality of use.

The working principle of the invention is as follows: in use, a prepared melt-blown non-woven raw material is sequentially placed into the first chamber 93 and the second chamber 94, then the micro-stepping motor 953 is started, when the micro-stepping motor 953 rotates clockwise, the screw 954 can drive the lower cover 955 and the upper cover 956 to synchronously ascend along the direction of the sliding column 958, when the lower cover 955 is clamped at the inner bottom end of the material barrel 951, the upper cover 956 can be separated from the top of the material barrel 951 until an interval appears, the raw material in the first chamber 93 and the second chamber 94 can enter the material barrel 951, after the material is filled, the micro-stepping motor 953 rotates anticlockwise, under the screw 954 can drive the lower cover 955 and the upper cover 956 to synchronously descend along the direction of the sliding column 958, when the upper cover 956 is clamped at the inner top end of the material barrel 951, the lower cover 955 can be separated from the bottom of the material barrel 951, until the interval appears, inside raw and other materials then can flow into the inside of blending barrel 4 from the interval, and outside counter then can record the number of times that raw and other materials were carried to the precision of raw and other materials use has been ensured.

At the moment, the driving motor 5 is started, the power driving end of the driving motor can drive the belt pulley set 6 to rotate, the stirring blades 8 can be driven to rotate and stir at a high speed under the action of the driving rod 7, various raw materials can be uniformly mixed, after uniform mixing, the valve 13 is opened, the raw materials are discharged from the discharge pipe 12, then the raw materials are subjected to melt extrusion granulation through the screw extruder, and finally the polylactic acid polyhydroxyalkanoate melt-blown nonwoven material can be prepared through the melt-blown process.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.