CN216182116U - Overheated wire pretensioning device for single polymer composite products - Google Patents

Abstract

The utility model relates to a single polymer composite product overheating wire pre-tightening device, and belongs to the technical field of polymer composite material forming and processing. The device comprises an outer frame, a fixed end, a fixed guide pillar, a tensioning block, a spring and a tensioning end. When the device is used, the continuous fiber is wound, one end of the continuous fiber is wound and fixed on the fixed end, the other end of the continuous fiber is fixed on the tightening end, the outer frame and the tightening block tighten the wound continuous fiber and apply pre-tightening force to the wound continuous fiber; the overheating characteristic of the polymer is utilized to enable the continuous fiber yarn to form the overheating yarn under the action of pretightening force, and the overheating yarn has a higher melting point. The device is used for preparing the single polymer composite material product with small density, high recycling rate and good interface cohesiveness, can establish a wider processing temperature window than the traditional preparation method, and can obtain the product with the mechanical strength close to the theoretical mechanical strength.

Description

Overheated wire preloading device for single polymer composite products

technical field

The utility model relates to a single-polymer composite material product overheated wire pre-tightening device, which belongs to the technical field of polymer composite material forming and processing.

Background technique

In recent years, fiber-reinforced polymer composites have been widely used and developed rapidly, especially to meet the urgent needs of lightweight development of automobiles. With the continuous attention to energy conservation and environmental protection, improving the recycling performance of fiber-reinforced polymer composites has become a research hotspot in related industry technologies. Traditional fiber-reinforced polymer composites are composed of a matrix and a reinforcement, usually with a polymer as the matrix and glass fiber, carbon fiber, boron fiber, aramid fiber, silicon carbide fiber, etc. as the reinforcement. The polymer matrix mainly includes two types of thermosetting polymers and thermoplastic polymers. Compared with thermosetting polymers that cannot be softened and re-molded when heated, thermoplastic polymers have the advantage of being reusable. It has a huge advantage in terms of recycling performance. However, due to the existence of reinforcements, it is more difficult to recycle the fiber-reinforced thermoplastic polymer composites, especially the fiber reinforcements of different materials from the thermoplastic polymer matrix cannot be separated. Therefore, the development of easily recyclable thermoplastic polymer composites has become an urgent need. Single polymer composite material is a composite material with thermoplastic polymer as matrix and the same thermoplastic polymer fiber as reinforcement. Polypropylene single polymer composite material is a single polymer composite material with polypropylene as matrix and polypropylene fiber as reinforcement. Because the matrix and reinforcement are all from the same thermoplastic polymer, the recycling efficiency is high, the cost is low, and it has great advantages in resource recycling and energy saving and emission reduction. Second, since thermoplastic polymer fibers have lower densities than traditional fiber reinforcements such as glass fibers and carbon fibers, single-polymer composites also have lower densities, which can further reduce weight. Furthermore, the matrix and reinforcement from the same thermoplastic polymer have good compatibility, and can obtain better interfacial bonding properties, and then have better mechanical strength, especially impact resistance; Creep and other aspects have unique advantages. At present, the thermoplastic polymers of the developed single-polymer composite materials mainly include polypropylene, polyethylene, polyethylene terephthalate, polyamide, polylactic acid, polyether ether ketone, etc. Polymer composite products are used in automobiles, luggage, sports, military and other fields. my country still lacks key technologies and equipment related to material preparation and structural molding.

Because the matrix and reinforcement of single-polymer composites are the same thermoplastic polymer and have the same and similar melting temperature (melting point), under the molding technology conditions of traditional fiber-reinforced thermoplastic polymer composites, especially at high heating temperatures Under certain conditions, the fiber reinforcement will melt and lose its reinforcing effect. Therefore, the traditional thermoplastic fiber-reinforced thermoplastic polymer composite molding technology cannot realize the preparation of single polymer composite materials. Establishing the melting temperature difference between the matrix and fibers belonging to the same thermoplastic polymer is the key to the preparation of single-polymer composites and their articles. The existing single-polymer composite material forming methods are mainly realized based on the hot pressing method, mainly including the fiber direct hot pressing method, the film layer hot pressing method and the co-extrusion skin-core fiber winding hot pressing method. The fiber direct hot pressing method is to directly lay the polymer continuous fiber filament or fiber cloth directly in the hot pressing mold, melt the surface of the polymer fiber through high temperature without melting in the middle, and then partially press the surface of the molten polymer fiber filament by high pressure. A matrix is formed, and the middle part of the unmelted polymer fiber filaments retains its reinforcing effect as a reinforcing body, and is finally cooled and solidified to form a single-polymer composite product. This method is extremely sensitive to temperature, and the hot-pressing temperature is usually in the range of 1 to 2°C around the melting point of the polymer fibers; the control accuracy of the hot-pressing temperature is extremely high. If the hot-pressing temperature is too high, the polymer fibers may be completely melted. The final product loses the reinforcing effect; if the hot pressing temperature is too low, the polymer fiber strands cannot be effectively bonded, and high mechanical strength cannot be achieved. The film layer hot pressing method uses the polymer continuous fiber filament or fiber cloth as the reinforcement, the polymer film as the matrix, and the fiber tow layer and the film layer are alternately stacked in the hot pressing mold; because the polymerization The material fiber has been drawn and stretched at high times in the preparation process, so it has a higher melting point than the polymer film; the hot pressing temperature is set at the temperature of the melting point of the polymer film and the melting point of the polymer fiber. The hot pressing process In the middle, the membrane melts while the fibers remain unmelted, and is then solidified by high pressure pressing and cooling to form a single polymer composite article. The hot-pressing temperature control window of this method is wider than that of the fiber direct hot-pressing method. The melting point difference formed by the homopolymerization and copolymerization of some polymers, different crystal forms and different molecular weights can be used to form a wider hot-pressing temperature window. However, there is also the problem of weakening of the strength produced by polymers of different crystalline properties. The co-extrusion skin-core fiber winding hot pressing method takes advantage of the characteristics that polymer homopolymerization and copolymerization can form different melting points. The fiber filaments or fiber strips that form the skin-core structure are wound on the frame, and then laid in a hot pressing mold. The hot pressing temperature is set between the melting point of the copolymer and the homopolymer, so that the copolymer melts as a Matrix, which keeps the homopolymer in the form of fibers as a reinforcement, and finally forms a single polymer composite product by high pressure pressing and cooling. This method is mainly limited to a small selection of raw materials, and currently only polypropylene has the characteristics of copolymerization and homopolymerization. The mechanical strength of copolymerized polypropylene is weaker than that of homopolypropylene, which also weakens the overall theoretical strength of single-polymer composites.

To sum up, the molding of single-polymer composite products is mainly realized by hot pressing. The key technology is to establish a wide hot pressing temperature window, that is, to establish the melting temperature difference between the polymer matrix and the reinforcement. On the one hand, the existing hot-pressing molding method of single-polymer composite materials is limited by a narrow temperature window, and on the other hand, the strength of the reinforcement is weakened during the molding process, and the strength of the final single-polymer composite material product is far from the theoretical strength. gap, the maximum strength that exerts the theoretical strength value cannot be obtained. The theoretical strength of a single-polymer composite mainly depends on the volume fraction of the reinforcement, the strength of the matrix and the reinforcement, and the orientation of the reinforcement. The strength of the reinforcement mainly depends on the orientation of the polymer chains in the polymer micromorphological structure. In the process of hot pressing, the strength of the reinforcement with a certain volume fraction will be weakened in the process of heating and cooling, which is mainly caused by the weakening of the diffusion and migration orientation of the polymer chains inside the reinforcement. Therefore, in order to make the mechanical strength of the single-polymer composite material closer to the theoretical strength of this structural composite material, it is necessary to further widen the processing temperature window, that is, the melting temperature difference between the matrix and the reinforcement, so as to ensure that the strength of the reinforcement does not change during the molding process. weakened or only slightly weakened.

SUMMARY OF THE INVENTION

The present invention aims to solve the above-mentioned technical problems at least to a certain extent.

The purpose of this utility model is to provide a single polymer composite material product overheated wire pre-tightening device, which can realize a wider processing temperature window, that is, establish a larger melting temperature difference between the matrix and the reinforcement, which can be used for batch continuous production of size Single polymer composite products with various shapes, low density, high recycling rate, good interface adhesion and higher mechanical strength.

The purpose of the utility model is achieved through the following technical solutions.

A single polymer composite material product overheated wire pre-tightening device, comprising an outer frame, a fixed end, a fixed guide post, a support block, a spring, and a tightening end, the fixed end is arranged at one end outside the outer frame, and the The fixed guide column is arranged on the outer frame, the holding block is arranged outside the outer frame, and can move along the axial direction of the fixed guide column, the spring is arranged between the holding block and the outer frame, and the tightening end is arranged on the outside At one end of the outer side of the frame, the single polymer composite product overheated filament pre-tightening device is wound with continuous fiber filaments when in use, one end of the continuous fiber filament is wound and fixed on the fixed end, and the other end of the continuous fiber filament is fixed on the tightening end. , the outer frame and the holding block hold the wound continuous fiber filament, and apply a pre-tightening force to the wound continuous fiber filament;

Further, the tightening end head includes a fixing frame and a knob, the fixing frame is provided with a knob mounting hole, the knob is mounted on the mounting hole of the fixing frame, and one end of the fixing frame is fixed on the outer side of the outer frame. When the continuous filament is wound, one end of the wound continuous filament is fixed at one end of the knob, and is further wound around the knob as the knob rotates. The distance between the holding block and the outer frame is reduced, the spring is compressed, and the size of the preload is determined by the compressed distance of the spring;

Further, the tightening end also includes a stop ratchet, a pawl and a stop spring, the stop ratchet is connected with the knob and can be rotated together with the knob, and the pawl is installed on the tightening end and can be tightened. The tight end moves on the head, one end of the pawl is embedded in the groove of the ratchet, and the other end of the pawl restricts the movable position by the stop spring;

Further, the single-polymer composite material product overheated wire pre-tightening device includes a number of fixed guide posts and a number of springs, the number of the fixed ends is 2, the number of the holding blocks is 2, and the number of the tightening ends is 2. The number is 2, and the outer frame is rectangular, one of which is parallel to the outside of the broad side of the outer frame, and the other is parallel to the outer side of the long side of the outer frame. A fixed guide post is arranged between the wide side or the long side of the outer frame, and a spring is sleeved on the fixed guide post;

Further, the single polymer composite product superheated filament preloading device is configured with an automatic winding device for automatically winding the continuous fiber tow onto the filament winding frame; and a robotic arm for automatic positioning and placement of the filament winding frame.

The single-polymer composite product forming device includes a superheated wire preloading device, a mold, a mold clamping system, and a temperature control system. It is characterized in that: the shape of the mold cavity is designed according to the shape of the product, the mold includes a male mold and a female mold, and the mold is installed. On the mold clamping system; the temperature control system controls the temperature of the prefabricated film at the position of the mold cavity and the temperature of the mold; the overheated wire preloading device is wound with polymer continuous fiber filaments when in use, and the wound is The polymer continuous filaments apply pre-tightening force, and are placed between the punch and the die of the mold when the product is formed, and the prefabricated film is combined with the prefabricated film under the action of the clamping system and the temperature control system to form the product.

The method steps of using the single-polymer composite material product overheating wire pre-tightening device of the present invention are as follows:

1) Preparation of polymer continuous filaments by melt spinning;

2) using the same polymer raw material to prepare the polymer membrane;

3) Place the polymer film in the clamping position, and quickly cool the polymer film to the supercooled temperature through the temperature control system;

4) winding the polymer continuous filaments on the overheated wire pre-tightening device, and applying a pre-tightening force to the wound polymer continuous filaments during and/or after winding;

5) Place the overheated wire pretensioning device wound with the polymer continuous filament in the clamping position;

6) The temperature of the mold is controlled by the temperature control system to be the supercooled temperature, and the mold is quickly closed by the mold clamping system, and the polymer continuous fiber filament and the diaphragm are compounded and molded;

7) After the pressing time is up, cooling is carried out through the temperature control system, the mold is opened after the cooling time is up, and the product is taken out;

8) Remove excess material other than the shape of the product to obtain the final product.

Wherein, the supercooling temperature>the crystallization temperature of the polymer raw material and <the melting point of the preloaded polymer continuous filaments.

beneficial effect

1. The single-polymer composite material product superheated wire pre-tightening device provided by the utility model utilizes the matrix and reinforcement of the single-polymer composite material to belong to the same kind of polymer material, and can continuously produce products with low density, high recycling rate, Single polymer composite products with good interfacial adhesion;

2. The single-polymer composite material product superheated wire pre-tightening device provided by the utility model can adjust the restraint traction ratio of the wound filament to form a pre-tightening force, and can realize the "overheating" of the fiber reinforcement by using the characteristics of polymer overheating , the "superheated silk" fibers have a higher melting point; therefore, the processing temperature window of the established single-polymer composites is widened;

3. The single polymer composite material product superheated wire pretensioning device provided by the utility model, the formed "superheated wire" polymer fiber reinforcement will not melt under supercooled temperature conditions, and the internal polymer chain orientation will not be If it is too affected, the reinforced structure can be completely maintained, so the final formed single-polymer composite article can have or approach the theoretical strength of the structural composite;

4. The single polymer composite material product superheated wire pretensioning device provided by the present invention can be used to prepare products of different sizes and shapes, and has the advantages of continuous batch production, high production efficiency, and high degree of automation;

5. The single-polymer composite material product superheated wire pre-tightening device provided by the utility model can be applied to the continuous fiber winding of various types of polymer raw materials, including polypropylene, polyethylene, polyethylene terephthalate, Polyamide, polylactic acid, polyetheretherketone, etc., the processing technology can be adjusted by measuring the melting point and crystallization temperature of polymer raw materials and fibers; in addition, it is not limited to the winding of polymer continuous fibers, other glass fibers, carbon fibers, natural fibers , metal fibers are applicable;

6. The single-polymer composite material product superheated wire pre-tightening device provided by the utility model has a wide application field of the prepared single-polymer composite material, can replace wood metal alloy and glass fiber composite material, and is widely used in aerospace, ships, The fields of automobile, communication electronics, building materials, medical equipment and fitness equipment can promote the development of new material technology and processing industry.

Description of drawings

Fig. 1 is the front view of embodiment 1;

Fig. 2 is the A-direction view in Fig. 1;

Fig. 3 is a partial enlarged view of B in Fig. 2;

4 is a front view of Example 1 in a state where the continuous filaments are stretched;

Fig. 5 is the schematic diagram of embodiment 1 when in use;

Fig. 6 is the partial enlarged view of embodiment 2;

Fig. 7 is the front view of embodiment 3;

In the figure: 1—outer frame, 2—fixed end, 3—fixed guide post, 4—holding block, 5—spring, 6—tightening end, 7—continuous fiber filament, 8—diaphragm, 9— Mold, 10—Clamping System, 11—Temperature Control System, 6-1—Fixing Frame, 6-2—Knob, 6-3—Simulating Ratchet, 6-4—Pawl, 6-5—Simulating Spring, 9-1—punch, 9-2—concave

Detailed ways

The preferred embodiments of the present utility model will be further described in detail below with reference to the accompanying drawings.

Example 1

A single-polymer composite material product overheating wire pre-tightening device, comprising an outer frame (1), a fixed end head (2), a fixed guide post (3), a holding block (4), a spring (5), a tightening end head (6), the fixed end head (2) is arranged on one end of the outer frame (1), the fixed guide post (3) is arranged on the outer frame (1), and the support block (4) is arranged on the outer frame (1) The outer side of the outer frame (1) can move along the axial direction of the fixed guide post (3), the spring (5) is arranged between the support block (4) and the outer frame (1), and the tightening end (6) is arranged At the outer end of the outer frame (1), the single-polymer composite product overheated filament pretensioning device is wound with continuous fiber filaments (7) during use, and one end of the continuous fiber filaments (7) is wound and fixed on the fixed end (2). , the other end of the continuous fiber filament (7) is fixed on the tightening end (6), the outer frame (1) and the tightening block (4) hold the wound continuous fiber filament (7), and the wound continuous fiber filament (7) is tightened. The filament (7) applies a pre-tightening force; further, the tightening end (6) includes a fixing frame (6-1) and a knob (6-2), and a knob (6-1) is provided on the fixing frame (6-1). 6-2) Mounting hole, the knob (6-2) is mounted on the mounting hole of the fixing frame (6-1), one end of the fixing frame (6-1) is fixed on the outer end of the outer frame (1), When in use, one end of the wound continuous filament (7) is fixed on one end of the knob (6-2), and is further wound around the knob (6-2) as the knob (6-2) rotates. ) by rotating and pulling the continuous fiber filament (7), and then applying a pre-tightening force to the continuous fiber filament (7), while the knob (6-2) is rotated, the space between the tension block (4) and the outer frame (1) The distance is reduced, the spring (5) is compressed, and the magnitude of the pre-tightening force is determined by the compressed distance of the spring (5); further, the tightening end (6) also includes a stopper ratchet (6-3). ), the pawl (6-4) and the stop spring (6-5), the stop ratchet (6-3) is connected with the knob (6-2), and can rotate together with the knob (6-2), the pawl (6-2) (6-4) is installed on the tightening end (6), and can move on the tightening end (6), one end of the pawl (6-4) is inserted into the groove of the quasi-ratchet (6-3), The other end of the pawl (6-4) restricts the movable position through a stop spring (6-5).

The single-polymer composite product forming device comprises an overheated wire pretensioning device, a mold (9), a mold clamping system (10), and a temperature control system (11), the mold (9) cavity shape is designed according to the product shape, and the mold ( 9) comprising a punch (9-1) and a concave die (9-2), the mould (9) is mounted on the mould clamping system (10); the temperature control system (11) controls the position of the cavity of the mould (9) The temperature of the prefabricated film (8) and the temperature of the mold (9); the overheated filament pretensioning device is wound with polymer continuous filaments (7) when in use, and the wound polymer continuous filaments (7) ) to apply a pre-tightening force, which is placed between the punch (9-1) and the concave die (9-2) of the mold (9) when the product is formed, and is connected with the prefabricated diaphragm (8) in the clamping system (10) and The composite molded product is made under the action of the temperature control system (11).

The method steps of using the single-polymer composite product overheated wire pretensioning device described in this embodiment are as follows:

1) preparing polymer continuous filaments (7) by melt spinning;

2) using the same polymer raw material to prepare a polymer membrane (8);

3) placing the polymer film (8) at the clamping position, and rapidly cooling the polymer film (8) to a supercooled temperature through the temperature control system (11);

4) winding the polymer continuous filament (7) on the overheated filament pretensioning device, and applying a pre-tightening force to the wound polymer continuous filament (7) during and/or after winding;

5) place the overheated wire pretensioning device wound with the polymer continuous filament (7) at the clamping position;

6) The temperature of the mold is controlled to be a supercooled temperature by the temperature control system (11), and the mold is quickly closed by the mold clamping system (10), and the polymer continuous fiber filament (7) and the diaphragm (8) are compositely pressed into molding;

7) After the pressing time is up, cooling is carried out by the temperature control system (11), the mold is opened after the cooling time is up, and the product is taken out;

8) Remove excess material other than the shape of the product to obtain the final product.

Wherein, the supercooling temperature>the crystallization temperature of the polymer raw material and <the melting point of the preloaded polymer continuous filaments.

Example 2

A single-polymer composite material product overheated wire pre-tightening device, on the basis of Example 1, the pawl (6-4) of the single-polymer composite material product overheated wire pre-tightening device adopts the method of stepped shaft pins, Insert the stop spring (6-5) into the small diameter shaft and install it in the small guide hole.

Example 3

A single polymer composite product overheated wire pretensioning device, on the basis of Example 1, the single polymer composite product overheated wire pretensioning device comprises 4 fixed guide posts (3), 4 springs (5). ), the number of the fixed ends (2) is 2, the number of the holding blocks (4) is 2, the number of the tightening ends (6) is 2, and the outer frame (1) is rectangular , one of the holding blocks (4) is arranged parallel to the outer side of the wide side of the outer frame (1), and the other holding block (4) is arranged parallel to the outer side of the long side of the outer frame (1). ) and the wide side or the long side of the outer frame (1) are provided with a fixed guide post (3), and a spring (5) is sleeved on the fixed guide post (3).

The present invention includes but is not limited to the above embodiments, and any equivalent replacement or partial improvement made under the spirit and principle of the present invention will be deemed to be within the protection scope of the present invention.

Claims (6)

1. A single polymer composite material product overheating wire pre-tightening device, comprising an outer frame, a fixed end, a fixed guide post, a support block, a spring, and a tightening end, and the fixed end is arranged at one end outside the outer frame, The fixed guide post is arranged on the outer frame, the holding block is arranged on the outside of the outer frame, the spring is arranged between the holding block and the outer frame, the tightening end is arranged at one end outside the outer frame, and one end of the continuous fiber is wound around It is fixed on the fixed end, the other end of the continuous fiber filament is fixed on the tightening end, and the outer frame and the tightening block support the wound continuous fiber filament. 2. The overheated wire pre-tightening device of a single polymer composite product according to claim 1, wherein the tightening end comprises a fixing frame and a knob, the fixing frame is provided with a knob mounting hole, and the knob is installed On the mounting hole of the fixing frame, one end of the fixing frame is fixed to one end outside the outer frame, and one end of the wound continuous filament is fixed to one end of the knob. 3. A single polymer composite product overheated wire pre-tightening device as claimed in claim 2, characterized in that: the tightening end further comprises a stopper ratchet, a pawl and a stopper spring, the stopper ratchet and the The knob is connected and rotated together with the knob. The pawl is installed on the tightening end and moves on the tightening end. One end of the pawl is embedded in the groove of the ratchet, and the other end of the pawl is limited by the stop spring. 4. A single polymer composite product overheated wire pretensioning device as claimed in claim 1, characterized in that: the single polymer composite product overheated wire pretensioning device comprises a plurality of fixed guide posts and a plurality of springs. The number of the fixed ends is 2, the number of the holding blocks is 2, the number of the tightening ends is 2, the outer frame is a rectangle, and one of the supporting blocks is arranged parallel to the outer side of the broad side of the outer frame. , another holding block is arranged parallel to the outer side of the long side of the outer frame, each holding block and the wide or long side of the outer frame is provided with a fixed guide post, and a spring is sleeved on the fixed guide post . 5. The single-polymer composite product superheated filament pretensioning device according to any one of claims 1 to 4, characterized in that: an automatic winding device for automatically winding the continuous fiber tow onto the filament winding frame is configured . 6. The overheated filament pretensioning device for single-polymer composite products according to any one of claims 1 to 4, characterized in that: a robotic arm for automatic positioning and placement of the filament winding frame is configured.

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