CN117802658A - Preparation method of antibacterial and flame retardant yarn - Google Patents

Abstract

The invention discloses a preparation method of an antibacterial flame-retardant yarn and a preparation method thereof: uniformly mixing PA6 granules and master batches according to a proportion, and melting by a screw extruder; controlling the rotating speed of a screw extruder, extruding the melt from a spinneret plate, and oiling after cooling by side blowing; pre-knotting the oiled fiber through a pre-network, guiding the pre-knotted fiber into a drawing roller for drawing, conveying the drawn fiber into a bulking box for bulking treatment, cooling the drawn fiber, knotting the network, and winding the cooled fiber to obtain the antibacterial flame-retardant yarn. The melting point of the masterbatch used in the invention is higher than that of the PA6 granules and lower than the temperature of a screw extruder, so that the masterbatch is softened but not thoroughly melted, the functional substance is not dispersed in the nylon melt, the softened masterbatch can be stably dispersed in the melt, the functional substance is uniformly dispersed in the nylon melt in a punctiform dispersion mode, the uniformity of the fiber after spinning molding is high, the stress concentration point is less, and the mechanical property of the functional fiber is limited.

Description

Preparation method of antibacterial and flame retardant yarn

Technical Field

The invention relates to the field of chemical fibers, and in particular to a method for preparing antibacterial and flame-retardant yarns.

Background technique

Automotive interior materials are an important part of the automotive industry terminal. Since the interior space of automobiles is relatively closed, chemical fiber materials used for automotive interiors should have good environmentally friendly properties, such as low volatile matter, antibacterial, and self-cleaning. In addition, the safety of chemical fibers used in automobile interiors is also particularly important. Flame-retardant and heat-insulating chemical fibers are used for interior decoration of automobiles, which can reduce violent combustion in the event of accidents.

Since the chemical fiber components used in automobile interiors are mostly traditional chemical fibers such as nylon, polyester, and polypropylene, these chemical fibers themselves do not have specific functional properties. Functional components need to be added before fiber molding, such as in polyamide pellets. Add _TiO2 masterbatch, melt them together and spin to prepare nylon fiber with UV resistance. Usually functional components are small molecule solid agents, which have certain compatibility difficulties with the main body of chemical fibers, resulting in uneven distribution of functional components in chemical fibers, inability to achieve corresponding effects, and reduced mechanical properties of chemical fibers.

Contents of the invention

Aiming at the problems of poor effect and reduced mechanical properties caused by uneven distribution of functional components in existing functional chemical fibers, the present invention provides a method for preparing antibacterial and flame-retardant yarns, which includes the following steps:

1) Mix and melt

Mix PA6 pellets and masterbatch evenly according to the proportion and melt them using a screw extruder;

2) Spinneret solidification

Control the speed of the screw extruder to extrude the melt from the spinneret, cool it with side blowing and then apply oil;

3) Forming

The oiled fibers are pre-knotted through a pre-network, introduced to a drafting roller for drawing, and then transported to a puffing and deformation box for expansion treatment. After cooling, the network is knotted, and the antibacterial resistance is obtained after winding. Burn yarn.

According to the above method, the present invention controls the melting point of PA6 pellets to be 255-265°C, the melting point of masterbatch to be 265-280°C, and the heating temperature of the screw extruder to be 260-275°C. Based on the control of the above process parameters, the present invention can solve the above technical problems, and its technical principle is: the melting point of the masterbatch is higher than that of the PA6 pellets but lower than the temperature of the screw extruder, so the masterbatch will soften but not completely melt after the PA6 pellets are melted, so that the functional substances in the masterbatch will not be dispersed into the nylon melt, or a small part of the functional particles will be dispersed in the nylon melt, and the main material of the softened masterbatch is close to the nylon component, and can be stably dispersed in the melt, so that the functional substances are uniformly dispersed in the nylon melt in the form of point dispersion, the uniformity of the fiber after spinning is high, the stress concentration points caused by particle agglomeration are few, and the mechanical properties of the functional fiber are limited compared with pure fiber. In addition, since the softened masterbatch solidifies again after fiber forming, small particles enriched with functional substances will be formed, and the effect is more obvious.

Specifically, the masterbatch used in the present invention is composed of polyamide, antibacterial agent and flame retardant, and the mass ratio is 100: (0.5-2): (1-3). The polyamide is PA6 or PA66, and the antibacterial agent is nano zinc oxide. , nano copper oxide or nano silver powder, the flame retardant is one of dibromomethane, trichlorobromomethane, melamine or decabromodiphenyl ether; the dosage of masterbatch is 0.1% to 2% of the weight of PA6 pellets .

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a SEM image of the antibacterial flame-retardant nylon yarn obtained in Example 1.

Detailed ways

The present invention is described below in conjunction with examples, which are only used to explain the present invention and are not used to limit the scope of the present invention.

Example 1

A method for preparing antibacterial and flame-retardant nylon yarn, including the following steps: select PA6 pellets with a melting point of 265°C and masterbatch with a melting point of 275°C and mix them evenly in proportion. The amount of masterbatch is 2wt% of the PA6 pellets. Control the temperatures in zones one to five of the screw extruder to be 269°C, 266°C, 270°C, 272°C, and 268°C respectively. Control the speed of the screw extruder to extrude the melt from the spinneret. After 18 Side blow cooling with humidity of 80%, side blow speed is 0.3m/s. After side blowing, the fiber bundles are oiled with an oiling rate of 1%. After oiling, they enter the pre-network for pre-knotting, and then are introduced into drafting. It is drafted on the roller with a drafting multiple of 2, and then transported to the expansion and deformation box, where it is expanded at 180°C and the expansion pressure is 6 bar. After cooling, the antibacterial and flame-retardant yarn is obtained.

The masterbatch used in this embodiment is composed of polyamide, antibacterial agent and flame retardant, with a mass ratio of 100:1:2, in which the polyamide is PA66, the antibacterial agent is nano zinc oxide, and the flame retardant is methylene bromide.

Example 2

A method for preparing antibacterial and flame-retardant nylon yarn, including the following steps: select PA6 pellets with a melting point of 255°C and masterbatch with a melting point of 265°C and mix them evenly in proportion. The amount of masterbatch is 0.1wt% of the PA6 pellets. , control the temperatures in zones one to five of the screw extruder to be 262°C, 257°C, 259°C, 256°C, and 260°C respectively. Control the speed of the screw extruder to extrude the melt from the spinneret. Side blow cooling with 16°C humidity and 70% side blow wind speed is 0.25m/s. After side blowing, the fiber bundles are oiled with an oiling rate of 1.5%. After oiling, they enter the pre-network for pre-knotting, and then are introduced into the traction It is drafted on the stretching roller with a draft ratio of 1.8, and then transported to the expansion and deformation box, where it is expanded at 160°C and the expansion pressure is 5 bar. After cooling, the antibacterial and flame-retardant yarn is obtained.

The masterbatch used in this embodiment is composed of polyamide, antibacterial agent and flame retardant, with a mass ratio of 100:0.5:1, in which the polyamide is PA6, the antibacterial agent is nano silver powder, and the flame retardant is decabromodiphenyl ether.

Example 3

A method for preparing antibacterial and flame-retardant nylon yarn, including the following steps: select PA6 pellets with a melting point of 260°C and masterbatch with a melting point of 270°C and mix them evenly in proportion. The amount of masterbatch is 1wt% of the PA6 pellets. Control the temperatures in zones one to five of the screw extruder to be 261°C, 264°C, 266°C, 266°C, and 265°C respectively. Control the speed of the screw extruder to extrude the melt from the spinneret. After 20 Side blow cooling with 90% humidity at ℃. The side blow speed is 0.4m/s. After side blowing, the fiber bundles are oiled with an oiling rate of 2%. After oiling, they enter the pre-network for pre-knotting and then into drafting. It is drafted on the roller with a draft ratio of 2.2, and then transported to the expansion and deformation box, where it is expanded at 190°C and the expansion pressure is 7 bar. After cooling, the antibacterial and flame-retardant yarn is obtained.

The masterbatch used in this embodiment is composed of polyamide, antibacterial agent and flame retardant, with a mass ratio of 100:0.75:3, in which the polyamide is PA66, the antibacterial agent is nano zinc oxide, and the flame retardant is melamine.

Comparative example 1

A method for preparing antibacterial and flame-retardant nylon yarn, including the following steps: Select PA6 pellets with a melting point of 265°C and the same PA6 pellets as the carrier masterbatch, mix them evenly in proportion, and the amount of masterbatch is 10% of the PA6 pellets. 2wt%, control the temperatures of zones one to five of the screw extruder to be 269°C, 266°C, 270°C, 272°C, and 268°C respectively. Control the speed of the screw extruder to extrude the melt from the spinneret. , cooled by side blowing at 18°C with a humidity of 80%. The side blowing wind speed is 0.3m/s. After side blowing, the fiber bundles are oiled with an oiling rate of 1%. After oiling, they enter the pre-network for pre-knotting, and then It is introduced into the drafting roller for drafting, and the drafting multiple is 2, and then transported to the puffing and deformation box, where it is puffed at 180°C with a puffing pressure of 6 bar. After cooling, the antibacterial and flame-retardant yarn is obtained.

The masterbatch used in Comparative Example 1 is added with nano zinc oxide antibacterial agent and dibromomethane flame retardant, and the mass ratio of PA6 component, nano zinc oxide and dibromomethane is 100:1:2.

Blank example 1

A method for preparing nylon yarn, including the following steps: select PA6 pellets with a melting point of 265°C, add them to a screw extruder, and control the temperatures of zones one to five of the screw extruder to be 269°C and 266°C respectively. , 270℃, 272℃, 268℃, control the speed of the screw extruder, extrude the melt from the spinneret, and cool it with side blowing at 18℃ and 80% humidity. The side blowing wind speed is 0.3m/s. After blowing, the fiber bundles are oiled with an oiling rate of 1%. After oiling, they enter the pre-network for pre-knotting, and then are introduced to the drafting roller for drafting. The drafting multiple is 2, and then transported to the puffing and deformation box. The puffing process is carried out at 180°C, the puffing pressure is 6 bar, and the antibacterial and flame-retardant yarn is obtained after cooling.

Examples 1-3, Comparative Example 1 and Blank Example 1 all use the same 10-hole spinneret assembly to prepare fibers of three specifications: 10dtex, 20dtex and 30dtex respectively. Take the fiber bundles before pre-networking and test the mechanical properties as shown in the table 1 shown.

Table 1. Performance testing of fiber bundles obtained in Examples 1-3, Comparative Example 1, and Blank Example 1

It can be seen from the data in Table 1 that the mechanical properties of the fiber bundles before pre-network obtained in Examples 1-3 are limited compared with the pure nylon fiber bundles obtained in Blank Example 1. The breaking strength of the nylon fiber bundle obtained in Example 1 is higher than that in Comparative Example 1, and the breaking elongation is also higher than that in Comparative Example 1. This is because the masterbatch in the nylon fiber obtained in Example 1 is evenly dispersed in a dotted manner, while the preparation method of Comparative Example 1 is to completely melt the masterbatch and disperse the functional substance in the nylon matrix, which will result in uneven distribution, and many stress concentration points, resulting in poor tensile strength and elongation.

Table 2 shows the antibacterial property test results and flame retardancy test results of the yarns obtained in Examples 1-3 and Comparative Example 1 according to GB/T20944.2-2007 standard.

Table 2. Antibacterial and flame retardant testing of yarns in Examples 1-3 and Comparative Example 1

It can be seen from the data in Table 2 that the antibacterial and flame-retardant nylon yarn obtained in Examples 1-3 has excellent antibacterial and flame retardant properties, while the antibacterial and flame-retardant nylon yarn obtained in Comparative Example 1 has antibacterial and flame-retardant properties due to uneven dispersion of functional substances. The flame retardancy is not ideal.

Figure 1 is an SEM image of the antibacterial and flame-retardant nylon yarn obtained in Example 1. It can be seen from the figure that the main structure of the fiber is dense and has no defects. Masterbatch particles are evenly distributed on the surface and there is no agglomeration of nanoscale particles. This illustrates that this The principle of the invention is feasible. The masterbatch in the nylon yarn prepared by the method of Example 1 is not completely melted but is dispersed in the nylon body in the form of point-like uniform dispersion.

The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection of the present invention. within the range.

Claims (5)

1. The preparation method of the antibacterial flame-retardant yarn is characterized by comprising the following steps of:

1) Mixing and melting

Uniformly mixing PA6 granules and master batches according to a proportion, and melting by a screw extruder;

2) Spinning coagulation

Controlling the rotating speed of a screw extruder, extruding the melt from a spinneret plate, and oiling after cooling by side blowing;

3) Shaping

Pre-knotting the oiled fiber through a pre-network, guiding the pre-knotted fiber into a drawing roller for drawing, conveying the drawn fiber into a bulking box for bulking treatment, cooling the drawn fiber, knotting the network, and winding the cooled fiber to obtain the antibacterial flame-retardant yarn.

2. The method according to claim 1, wherein in the step 1), the master batch consists of polyamide, an antibacterial agent and a flame retardant, and the mass ratio is 100 (0.5-2): 1-3.

3. The method of claim 2, wherein the polyamide is PA6 or PA66; the antibacterial agent is one of nano zinc oxide, nano copper oxide or nano silver powder; the flame retardant is one of dibromomethane, trichlorobromomethane, melamine or decabromodiphenyl ether.

4. A process according to any one of claims 1-3, wherein in step 1) the PA6 pellets have a melting point of 255-265 ℃ and the masterbatch has a melting point of 265-280 ℃; the heating temperature of the screw extruder is 260-275 ℃.

5. A process according to any one of claims 1 to 3, wherein the masterbatch is present in an amount of 0.1% to 2% by weight of the PA6 granulate.