CN111021090A - Portable leather handbag - Google Patents

Abstract

The invention relates to the technical field of high polymer materials, in particular to a portable leather bag, which comprises a bag body and a bag belt, wherein the bag body is made of PU leather, and the preparation method of the PU leather comprises the following steps: (1) preparing uncrosslinked silicone rubber particles; (2) preparation of the polyurethane mixture: heating unsaturated polyester resin to 120-130 ℃, adding an antioxidant and non-crosslinked silicone rubber particles, stirring for 30-45min, adding diisocyanate and a chain extender while stirring until the power of a stirring motor rises by 2 times, stopping stirring, and discharging to obtain a polyurethane mixture; (3) and (4) extrusion molding. The invention has the advantages that the PU leather has elasticity, large hollowing cannot be formed in the PU leather, and the PU leather is not easy to cause local elasticity and strength reduction due to hollowing.

Description

Portable leather handbag

Technical Field

The invention relates to the technical field of high polymer materials, in particular to a portable leather handbag.

Background

At present, along with the social development, leather products are more and more popular, but because the leather products are limited by the quality of animals and the yield, artificial leather products are produced.

The existing common artificial leather mostly adopts PU leather, but the PU leather on the market is generally hard and dry in hand feeling, so that the elasticity of the artificial leather prepared by adopting foamed polyurethane is increased to become a new substitute product.

The above prior art solutions have the following drawbacks: when the polyurethane is foamed, because of the uncertainty of the foaming agent, the pores generated by the polyurethane are unevenly distributed, so that the rebound resilience of PU leather is unevenly distributed, and the situation that local bubbles are large to form hollows, so that the elasticity and the strength are greatly reduced is easy to occur, so that the improvement space is provided.

Disclosure of Invention

In view of the shortcomings of the prior art, it is an object of the present invention to provide a portable leather handbag with uniform elasticity distribution.

The above object of the present invention is achieved by the following technical solutions:

a carry-on leather bag comprises a bag body and a bag belt, wherein the bag body is made of PU leather, and the preparation method of the PU leather comprises the following steps:

(1) uncrosslinked silicone rubber particles were prepared as follows:

adding a foaming agent and a cross-linking agent into the silicone rubber, mixing uniformly, and granulating to obtain non-crosslinked silicone rubber particles;

(2) a polyurethane mixture was prepared as follows:

heating 100 parts by mass of unsaturated polyester resin to 120-130 ℃, adding 3-4 parts by mass of antioxidant and 20-25 parts by mass of non-crosslinked silicone rubber particles, stirring for 30-45min, adding diisocyanate and chain extender while stirring until the power of a stirring motor rises by 2 times, stopping stirring, and discharging to obtain a polyurethane mixture;

(3) and (3) extrusion molding, which comprises the following steps:

extruding the polyurethane mixture into sheet PU leather;

the melting point of the unsaturated polyester resin is lower than 110 ℃;

the silicon rubber particles comprise the following components in parts by mass:

100 parts of silicon rubber;

8-10 parts of a cross-linking agent;

1.5-2 parts of foaming agent.

By adopting the technical scheme, the foamed silicon rubber particles are doped into the PU leather, so that the PU leather has elasticity, the elasticity is provided by the foamed silicon rubber, and the PU leather cannot form large hollowing due to the fact that the silicon rubber is in a fixed state, and the situation that the local elasticity and the strength of the PU leather are reduced due to hollowing is avoided; the non-crosslinked silicone rubber particles are added into the unsaturated polyester resin at the temperature of 110-120 ℃, so that the silicone rubber is heated in the unsaturated polyester resin to be crosslinked and the foaming agent in the silicone rubber is heated and gasified to enable the silicone rubber to generate air holes, and further the silicone rubber particles are crosslinked and foamed in the unsaturated polyester resin, and because the unsaturated polyester resin contains unsaturated bonds, part of the unsaturated polyester resin is crosslinked with the silicone rubber particles through the excessive crosslinking agent in the silicone rubber, so that when the unsaturated polyester resin reacts with diisocyanate and a chain extender to form polyurethane, the silicone rubber particles are stably connected with the polyurethane through crosslinking, the condition that the polyurethane is incompatible with the silicone rubber and is separated is reduced, the silicone rubber is stably and uniformly distributed in the polyurethane, and further when the PU leather is stressed, the stress is shared through the crosslinked silicone rubber, the excellent physical properties of the crosslinked silicone rubber are fully utilized, so that the portable leather bag made of PU leather is durable and has longer service life; when the uncrosslinked silicone rubber particles are vulcanized and foamed in the unsaturated polyester resin, the foamed silicone rubber surface forms a porous structure, so that the unsaturated polyester resin is immersed in pores on the surface of the foamed silicone rubber particles, and the connection stability of the unsaturated polyester resin and the foamed silicone rubber particles is further improved.

The present invention in a preferred example may be further configured to: in the step (1), the uncrosslinked silicone rubber is granulated into spherical uncrosslinked silicone rubber particles.

By adopting the technical scheme, the shape of the spherical uncrosslinked silicone rubber particles is also close to the spherical shape after foaming, so that the foamed silicone rubber particles better bear the stress in each direction in the PU leather, the effect of reinforcing the PU leather by the foamed silicone rubber particles is better, the elasticity in each direction of the PU leather is better, and the hand feeling is better.

The present invention in a preferred example may be further configured to: the unsaturated polyester resin is prepared by polycondensation of hydroxyl-terminated polybutadiene and adipic acid.

By adopting the technical scheme, the low-temperature characteristic and the hydrolysis stability of the PU leather are good, the heat resistance is good, the portable leather bag can be suitable for cold and hot areas, and the applicability of the portable leather bag is improved.

The present invention in a preferred example may be further configured to: the foaming agent is a solid foaming agent.

By adopting the technical scheme, the foaming agent is easily uniformly dispersed in the silicone rubber through mixing, so that the silicone rubber has a good foaming effect.

The present invention in a preferred example may be further configured to: the foaming agent is carbonate.

By adopting the technical scheme, through the characteristic that carbonate is insoluble in alcohol, after the uncrosslinked silicon rubber particles are added into the unsaturated polyester resin, the condition that the foaming effect is lost due to the dissolution of the foaming agent is avoided.

The present invention in a preferred example may be further configured to: in the step (3), the polyurethane mixture is extruded into the sheet-shaped PU leather, and then is cooled by cooling water with the temperature of below 15 ℃.

By adopting the technical scheme, the flow displacement of the foamed silicon rubber particles in the PU leather is reduced through low-temperature quick cooling, and the agglomeration is reduced, so that the foamed silicon rubber particles are stably and uniformly distributed in the PU leather.

The present invention in a preferred example may be further configured to: and (4) air-drying the PU leather cooled in the step (3), and then coating a water-based matte finishing agent.

By adopting the technical scheme, the PU leather surface has better hand feeling and more natural and vivid appearance by coating the water-based matte finishing agent.

The present invention in a preferred example may be further configured to: the water-based matte finishing agent comprises the following components in parts by weight:

25 parts of waterborne polyurethane;

55-65 parts of pure water;

5-8 parts of an organic silicon hand feeling agent;

1-3 parts of a leveling agent;

0.2-0.4 part of defoaming agent;

3-5 parts of a flatting agent;

3-5 parts of lotus leaf powder;

the waterborne polyurethane is self-crosslinking waterborne polyurethane.

By adopting the technical scheme, the hand feeling of the PU leather is closer to that of natural leather through the organic silicon hand feeling agent, so that the simulation degree of the PU leather is improved; by adding the lotus leaf powder, the hydrophobicity of the PU is better, the PU leather has better waterproof performance, and then the carried leather bag can better protect articles stored in the bag in rainy days.

The present invention in a preferred example may be further configured to: the preparation method of the water-based matte finishing agent comprises the following steps:

(1) adding waterborne polyurethane into pure water, and stirring uniformly to form a waterborne polyurethane solution;

(2) adding an organic silicon hand feeling agent, a flatting agent, a defoaming agent and a flatting agent into the aqueous polyurethane solution, and uniformly stirring to form a premix;

(3) adding lotus leaf powder into the premix, and uniformly stirring to form the aqueous matte finishing agent.

By adopting the technical scheme, the lotus leaf powder is added at last, so that the condition that the hydrophobic property of the lotus leaf powder influences the dissolution of the waterborne polyurethane to cause difficulty in uniformly mixing with each component is avoided.

In summary, the invention includes at least one of the following beneficial technical effects:

1. the PU leather has elasticity by doping the foamed silicon rubber particles, the elasticity is provided by the foamed silicon rubber, and the PU leather cannot form large hollowing due to the fact that the silicon rubber is in a fixed state, so that the situation that the local elasticity and the strength of the PU leather are reduced due to hollowing is avoided;

2. the uncrosslinked silicone rubber particles are added into the unsaturated polyester resin at the temperature of 110-120 ℃, so that the silicone rubber is heated in the unsaturated polyester resin to be crosslinked and foamed, and part of the unsaturated polyester resin is crosslinked with the silicone rubber particles through an excessive crosslinking agent in the silicone rubber, so that the excellent physical properties of the crosslinked silicone rubber are fully utilized, and the portable leather bag made of the PU leather is durable and has a long service life;

3. by adding the lotus leaf powder, the hydrophobicity of the PU is better, the PU leather has better waterproof performance, and then the carried leather bag can better protect articles stored in the bag in rainy days.

Drawings

FIG. 1 is a schematic flow chart of a process for preparing PU leather in the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

In the following examples, a one-pack self-crosslinking type aqueous polyurethane resin available from Mitsui chemical corporation was used as the self-crosslinking aqueous polyurethane.

In the following examples, silicone hand agents Silok-3538, available from Stokes Polymer Ltd, Guangzhou, were used.

In the following examples, the silicone leveling agent used was Silok-354, a silicone leveling agent of Polymer Ltd, Storocco, Guangzhou.

In the following examples, as the silicone defoaming agent, Silok-4500, which is a water-based silicone defoaming agent available from Polymer Ltd of Storocco, Guangzhou, was used.

In the following examples, S6 organic matting agent from san Source industries, Ltd, Dongguan was used as the matting agent.

In the following examples, antioxidant 1010 from BASF corporation (China) was used as the antioxidant.

Example 1

A portable leather bag comprises a bag body made of PU leather and a bag belt.

Referring to fig. 1, the preparation method of the PU leather includes the following steps:

(1) uncrosslinked silicone rubber particles were prepared as follows:

adding 100kg of silicon rubber into an open mill, at a roller speed of 30r/min, at a roller spacing of 5mm, plasticating for 30s, adding 1.5kg of foaming agent and 8kg of crosslinking agent, at a roller speed of 45r/min, at a roller spacing of 3mm, at a roller speed of 60r/min, at a roller spacing of 1.5mm, at a roller mixing time of 45s, at a roller speed of 60r/min, at a roller spacing of 45.5 mm, at a roller mixing time of 45s, discharging rubber into a double-screw extruder, extruding into a granulator, and granulating into spherical non-crosslinked silicon rubber particles with a particle size of 0.;

(2) a polyurethane mixture was prepared as follows:

adding 100kg of unsaturated polyester resin into a stirring kettle, heating to 120 ℃ of the unsaturated polyester resin, stirring at a rotating speed of 500r/min, adding 3kg of antioxidant and 20kg of non-crosslinked silicone rubber particles while stirring at a rotating speed of 1000r/min, stirring for 45min, then keeping the rotating speed of 1000r/min, adding 13.76kg of diisocyanate and 0.45kg of chain extender while stirring, continuously stirring until the power of a motor rises by 2 times, stopping stirring, and rapidly discharging to obtain a polyurethane mixture;

(3) and (3) extrusion molding, which comprises the following steps:

directly unloading the polyurethane mixture from the stirring kettle into a double-screw extruder for extrusion, tabletting the polyurethane mixture through a double-roller calender, cooling the polyurethane mixture at the position where the polyurethane mixture is discharged by spraying cooling water with the temperature of 12 ℃, carrying out air cooling and drying through an air cooling line to form PU leather, spraying a water-based matte finishing agent on the surface of the PU leather, and rolling the PU leather after the water-based matte finishing agent is naturally dried and solidified to finish the preparation.

In this embodiment, the foaming agent is carbonate, specifically, sodium bicarbonate, and in other embodiments, calcium carbonate, magnesium carbonate, or the like may be used.

In this embodiment, the crosslinking agent is a peroxide crosslinking agent, specifically dicumyl peroxide (DCP), and in other embodiments, benzoyl peroxide, di-t-butyl peroxide, dicumyl hydroperoxide, or the like may also be used.

In this example, the unsaturated polyester resin is obtained by polycondensation of hydroxyl-terminated polybutadiene and adipic acid, and the molecular weight of the unsaturated polyester resin is 2000.

In this example, 4' -diphenylmethane diisocyanate was used as the diisocyanate.

In this example, 1, 4-butanediol was used as the chain extender.

The preparation method of the water-based matte finishing agent comprises the following steps:

a. adding 25kg of waterborne polyurethane and 55kg of pure water into a stirring kettle, stirring at the rotating speed of 600r/min for 10min to form a waterborne polyurethane solution;

b. adding 8kg of organic silicon hand feeling agent, 3kg of flatting agent, 0.2kg of defoaming agent and 5kg of flatting agent into the aqueous polyurethane solution while stirring, rotating at the speed of 800r/min, and stirring for 15min to form a premix;

c. and (3) adding 3kg of lotus leaf powder into the premix while stirring at the rotating speed of 1000r/min, stirring for 10min, and then discharging to form the water-based matte finishing agent.

Example 2

A portable leather bag comprises a bag body made of PU leather and a bag belt.

Referring to fig. 1, the preparation method of the PU leather includes the following steps:

(1) uncrosslinked silicone rubber particles were prepared as follows:

adding 100kg of silicon rubber into an open mill, at a roller speed of 30r/min, at a roller spacing of 5mm, plasticating for 30s, adding 2kg of foaming agent and 10kg of crosslinking agent, at a roller speed of 45r/min, at a roller spacing of 3mm, at a roller mixing speed of 45s, at a roller speed of 60r/min, at a roller spacing of 1.5mm, at a mixing speed of 45s, discharging rubber into a double-screw extruder, extruding into a granulator, and granulating into spherical non-crosslinked silicon rubber particles with the particle size of 0.3mm +/-0.05 mm;

(2) a polyurethane mixture was prepared as follows:

adding 100kg of unsaturated polyester resin into a stirring kettle, heating to 130 ℃ of the unsaturated polyester resin, stirring at a rotating speed of 500r/min, adding 4kg of antioxidant and 25kg of non-crosslinked silicone rubber particles while stirring at a rotating speed of 1000r/min, stirring for 30min, then keeping the rotating speed of 1000r/min while stirring, adding 13.76kg of diisocyanate and 0.45kg of chain extender, continuously stirring until the power of a motor rises by 2 times, stopping stirring, and rapidly discharging to obtain a polyurethane mixture;

(3) and (3) extrusion molding, which comprises the following steps:

directly unloading the polyurethane mixture from the stirring kettle into a double-screw extruder for extrusion, tabletting the polyurethane mixture through a double-roller calender, cooling the polyurethane mixture at the position where the polyurethane mixture is discharged by spraying cooling water with the temperature of 12 ℃, carrying out air cooling and drying through an air cooling line to form PU leather, spraying a water-based matte finishing agent on the surface of the PU leather, and rolling the PU leather after the water-based matte finishing agent is naturally dried and solidified to finish the preparation.

In this embodiment, the foaming agent is carbonate, specifically, sodium bicarbonate is used.

In this embodiment, a peroxide crosslinking agent is used as the crosslinking agent, specifically, dicumyl peroxide (DCP) is used.

In this example, the unsaturated polyester resin is obtained by polycondensation of hydroxyl-terminated polybutadiene and adipic acid, and the molecular weight of the unsaturated polyester resin is 2000.

In this example, 4' -diphenylmethane diisocyanate was used as the diisocyanate.

In this example, 1, 4-butanediol was used as the chain extender.

The preparation method of the water-based matte finishing agent comprises the following steps:

a. adding 25kg of waterborne polyurethane and 65kg of pure water into a stirring kettle, stirring at the rotating speed of 600r/min for 10min to form a waterborne polyurethane solution;

b. adding 5kg of organic silicon hand feeling agent, 1kg of flatting agent, 0.4kg of defoaming agent and 3kg of flatting agent into the aqueous polyurethane solution while stirring, rotating speed of 800r/min, and stirring for 15min to form a premix;

c. and rotating at the speed of 1000r/min, adding 5kg of lotus leaf powder into the premix while stirring, stirring for 10min, and then discharging to form the water-based matte finishing agent.

Example 3

A portable leather bag comprises a bag body made of PU leather and a bag belt.

Referring to fig. 1, the preparation method of the PU leather includes the following steps:

(1) uncrosslinked silicone rubber particles were prepared as follows:

adding 100kg of silicon rubber into an open mill, at a roller speed of 30r/min, at a roller spacing of 5mm, plasticating for 30s, adding 1.8kg of foaming agent and 9.6kg of cross-linking agent, at a roller speed of 45r/min, at a roller spacing of 3mm, mixing for 45s, at a roller speed of 60r/min, at a roller spacing of 1.5mm, mixing for 45s, discharging rubber into a double-screw extruder, extruding into a granulator, and granulating into spherical non-crosslinked silicon rubber particles with the particle size of 0.3mm +/-0.05 mm;

(2) a polyurethane mixture was prepared as follows:

adding 100kg of unsaturated polyester resin into a stirring kettle, heating to 120 ℃ of the unsaturated polyester resin, stirring at a rotating speed of 500r/min, adding 3.2kg of antioxidant and 22.8kg of non-crosslinked silicone rubber particles while stirring, stirring at a rotating speed of 1000r/min for 45min, then adding 13.76kg of diisocyanate and 0.45kg of chain extender while stirring at a rotating speed of 1000r/min, continuously stirring until the power of a motor rises by 2 times, stopping stirring and rapidly discharging to obtain a polyurethane mixture;

(3) and (3) extrusion molding, which comprises the following steps:

directly unloading the polyurethane mixture from the stirring kettle into a double-screw extruder for extrusion, tabletting the polyurethane mixture through a double-roller calender, cooling the polyurethane mixture at the position where the polyurethane mixture is discharged by spraying cooling water with the temperature of 12 ℃, carrying out air cooling and drying through an air cooling line to form PU leather, spraying a water-based matte finishing agent on the surface of the PU leather, and rolling the PU leather after the water-based matte finishing agent is naturally dried and solidified to finish the preparation.

Sodium bicarbonate was used as the blowing agent in this example.

In this example, dicumyl peroxide (DCP) was used as the crosslinking agent.

In this example, the unsaturated polyester resin is obtained by polycondensation of hydroxyl-terminated polybutadiene and adipic acid, and the molecular weight of the unsaturated polyester resin is 2000.

In this example, 4' -diphenylmethane diisocyanate was used as the diisocyanate.

In this example, 1, 4-butanediol was used as the chain extender.

The preparation method of the water-based matte finishing agent comprises the following steps:

a. adding 25kg of waterborne polyurethane and 60kg of pure water into a stirring kettle, stirring at the rotating speed of 600r/min for 10min to form a waterborne polyurethane solution;

b. adding 6kg of organic silicon hand feeling agent, 2kg of flatting agent, 0.3kg of defoaming agent and 4kg of flatting agent into the aqueous polyurethane solution while stirring, rotating speed is 800r/min, and stirring for 15min to form a premix;

c. rotating at 1000r/min, adding 4kg of lotus leaf powder into the premix while stirring, stirring for 10min, and discharging to form the water-based matte finishing agent.

Comparative example 1

A portable leather bag comprises a bag body made of PU leather and a bag belt.

The preparation method of the PU leather comprises the following steps:

(1) crosslinked silicone rubber particles were prepared as follows:

adding 100kg of silicon rubber into an open mill, at a roller speed of 30r/min, at a roller spacing of 5mm and during plastication for 30s, adding 1.8kg of foaming agent and 9.6kg of cross-linking agent, at a roller speed of 45r/min, at a roller spacing of 3mm, mixing for 45s, at a roller speed of 60r/min, at a roller spacing of 1.5mm and mixing for 45s, discharging rubber into a double-screw extruder, extruding into a granulator, granulating into spherical non-crosslinked silicon rubber particles with the particle size of 0.3mm +/-0.05 mm, and foaming and vulcanizing by a flat vulcanizing machine and a die to form spherical crosslinked silicon rubber particles;

(2) a polyurethane mixture was prepared as follows:

adding 100kg of unsaturated polyester resin into a stirring kettle, heating to 120 ℃ of the unsaturated polyester resin, stirring at a rotating speed of 500r/min, adding 3.2kg of antioxidant and 22.8kg of crosslinked silicone rubber particles while stirring at a rotating speed of 1000r/min, stirring for 45min, then keeping the rotating speed of 1000r/min, adding 13.76kg of diisocyanate and 0.45kg of chain extender while stirring, continuously stirring until the power of a motor rises by 2 times, stopping stirring, and quickly discharging to obtain a polyurethane mixture;

(3) and (3) extrusion molding, which comprises the following steps:

directly unloading the polyurethane mixture into a double-screw extruder from a stirring kettle, extruding, tabletting by a double-roller calender, cooling by spraying cooling water with the temperature of 12 ℃ at a tablet outlet, air-cooling and drying by an air-cooling line to form PU leather, spraying the water-based matte finishing agent on the surface of the PU leather, and rolling the PU leather after the water-based matte finishing agent is naturally dried and solidified to finish the preparation.

Sodium bicarbonate was used as the blowing agent in this example.

In this example, dicumyl peroxide (DCP) was used as the crosslinking agent.

In this example, the unsaturated polyester resin is obtained by polycondensation of hydroxyl-terminated polybutadiene and adipic acid, and the molecular weight of the unsaturated polyester resin is 2000.

In this example, 4' -diphenylmethane diisocyanate was used as the diisocyanate.

In this example, 1, 4-butanediol was used as the chain extender.

The preparation method of the water-based matte finishing agent comprises the following steps:

a. adding 25kg of waterborne polyurethane and 60kg of pure water into a stirring kettle, stirring at the rotating speed of 600r/min for 10min to form a waterborne polyurethane solution;

b. adding 6kg of organic silicon hand feeling agent, 2kg of flatting agent, 0.3kg of defoaming agent and 4kg of flatting agent into the aqueous polyurethane solution while stirring, rotating speed is 800r/min, and stirring for 15min to form a premix;

c. rotating at 1000r/min, adding 4kg of lotus leaf powder into the premix while stirring, stirring for 10min, and discharging to form the water-based matte finishing agent.

Comparative example 2

A portable leather bag comprises a bag body made of PU leather and a bag belt.

The preparation method of the PU leather comprises the following steps:

(1) a polyurethane mixture was prepared as follows:

adding 100kg of unsaturated polyester resin into a stirring kettle, heating to 120 ℃ of the unsaturated polyester resin, stirring at a rotating speed of 500r/min, adding 3.2kg of antioxidant at a rotating speed of 1000r/min while stirring, stirring for 45min, keeping the rotating speed of 1000r/min while stirring, adding 13.76kg of diisocyanate and 0.45kg of chain extender, continuously stirring until the power of a motor rises by 2 times, stopping stirring, and quickly discharging to obtain a polyurethane mixture;

(2) and (3) extrusion molding, which comprises the following steps:

directly discharging the polyurethane mixture from a stirring kettle into a double-screw extruder for extrusion granulation to form polyurethane particles, directly discharging the polyurethane particles into a dry stirring kettle, adding 1.8kg of foaming agent, uniformly stirring, then pressing and foaming through a flat vulcanizing machine, cooling to form PU leather, spraying a water-based matte treating agent on the surface of the PU leather, naturally drying and solidifying the water-based matte treating agent, collecting the PU leather, and completing preparation.

Sodium bicarbonate was used as the blowing agent in this example.

In this example, the unsaturated polyester resin is obtained by polycondensation of hydroxyl-terminated polybutadiene and adipic acid, and the molecular weight of the unsaturated polyester resin is 2000.

In this example, 4' -diphenylmethane diisocyanate was used as the diisocyanate.

In this example, 1, 4-butanediol was used as the chain extender.

The preparation method of the water-based matte finishing agent comprises the following steps:

a. adding 25kg of waterborne polyurethane and 60kg of pure water into a stirring kettle, stirring at the rotating speed of 600r/min for 10min to form a waterborne polyurethane solution;

b. adding 6kg of organic silicon hand feeling agent, 2kg of flatting agent, 0.3kg of defoaming agent and 4kg of flatting agent into the aqueous polyurethane solution while stirring, rotating speed is 800r/min, and stirring for 15min to form a premix;

c. rotating at 1000r/min, adding 4kg of lotus leaf powder into the premix while stirring, stirring for 10min, and discharging to form the water-based matte finishing agent.

Comparative example 3

A portable leather bag comprises a bag body made of PU leather and a bag belt.

The preparation method of the PU leather comprises the following steps:

(1) uncrosslinked silicone rubber particles were prepared as follows:

adding 100kg of silicon rubber into an open mill, at a roller speed of 30r/min, at a roller spacing of 5mm, plasticating for 30s, adding 1.8kg of foaming agent and 9.6kg of cross-linking agent, at a roller speed of 45r/min, at a roller spacing of 3mm, mixing for 45s, at a roller speed of 60r/min, at a roller spacing of 1.5mm, mixing for 45s, discharging rubber into a double-screw extruder, extruding into a granulator, and granulating into spherical non-crosslinked silicon rubber particles with the particle size of 0.3mm +/-0.05 mm;

(2) a polyurethane mixture was prepared as follows:

adding 100kg of unsaturated polyester resin into a stirring kettle, heating to 120 ℃ of the unsaturated polyester resin, stirring at a rotating speed of 500r/min, adding 3.2kg of antioxidant and 22.8kg of non-crosslinked silicone rubber particles while stirring, stirring at a rotating speed of 1000r/min for 45min, then adding 13.76kg of diisocyanate and 0.45kg of chain extender while stirring at a rotating speed of 1000r/min, continuously stirring until the power of a motor rises by 2 times, stopping stirring and rapidly discharging to obtain a polyurethane mixture;

(3) and (3) extrusion molding, which comprises the following steps:

directly unloading the polyurethane mixture from the stirring kettle into a double-screw extruder for extrusion, tabletting the polyurethane mixture through a double-roller calender, cooling the polyurethane mixture at the position where the polyurethane mixture is discharged by spraying cooling water with the temperature of 12 ℃, carrying out air cooling and drying through an air cooling line to form PU leather, spraying a water-based matte finishing agent on the surface of the PU leather, and rolling the PU leather after the water-based matte finishing agent is naturally dried and solidified to finish the preparation.

Sodium bicarbonate was used as the blowing agent in this example.

In this example, dicumyl peroxide (DCP) was used as the crosslinking agent.

In this example, the unsaturated polyester resin is obtained by polycondensation of hydroxyl-terminated polybutadiene and adipic acid, and the molecular weight of the unsaturated polyester resin is 2000.

In this example, 4' -diphenylmethane diisocyanate was used as the diisocyanate.

In this example, 1, 4-butanediol was used as the chain extender.

The preparation method of the water-based matte finishing agent comprises the following steps:

a. adding 25kg of waterborne polyurethane and 60kg of pure water into a stirring kettle, stirring at the rotating speed of 600r/min for 10min to form a waterborne polyurethane solution;

b. adding 6kg of organic silicon hand feeling agent, 2kg of flatting agent, 0.3kg of defoaming agent and 4kg of flatting agent into the aqueous polyurethane solution while stirring, rotating speed is 800r/min, and stirring for 15min to form a premix;

c. rotating at 1000r/min, stirring for 10min, and discharging to obtain the water-based matte finishing agent.

Experiment 1

The PU leathers obtained in examples and comparative examples were tested for their rebound value (%) according to GB/T6670-2008 "determination of impact resilience by falling ball method for Flexible foam Polymer".

Experiment 2

The tensile strength of PU leathers prepared in examples and comparative examples was measured according to GB/T1040-2006 "determination of tensile Properties of plastics".

Experiment 3

The hydrophobic rate (%) of the adhesive was detected according to GB/T10299-2011 "test method for hydrophobicity of Heat insulating Material").

The test data of each example and comparative example are shown in Table 1

TABLE 1

According to table 1, can obtain, through adopting the silicon rubber granule to fill in PU leather, can obviously increase the resilience value of PU leather, elasticity is better, make and feel better, carry out the foaming vulcanization in putting into the unsaturated polyester resin of high temperature through the silicon rubber granule that does not vulcanize simultaneously, will make silicon rubber granule vulcanization in-process and unsaturated polyester resin take place partial crosslinking, make the silicon rubber granule produce effectual reinforcement effect to PU leather, make the resilience value and the tensile strength of PU leather all have obvious promotion.

The lotus leaf powder is added into the water-based matte finishing agent, so that the hydrophobicity of a coating formed on the surface of the PU leather by the water-based matte finishing agent is effectively improved, the hydrophobicity of the PU leather is greatly improved, and compared with common foamed polyurethane, the water-based matte finishing agent filled in the PU leather is beneficial to improving the hydrophobicity and reducing the water absorption of a foamed structure.

The embodiments of the present invention are preferred embodiments of the present invention, and the scope of the present invention is not limited by these embodiments, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.

Claims (9)

1. A carry-on leather bag comprises a bag body and a bag belt, and is characterized in that: the bag body is made of PU leather, and the preparation method of the PU leather comprises the following steps:

(1) uncrosslinked silicone rubber particles were prepared as follows:

adding a foaming agent and a cross-linking agent into the silicone rubber, mixing uniformly, and granulating to obtain non-crosslinked silicone rubber particles;

(2) a polyurethane mixture was prepared as follows:

heating 100 parts by mass of unsaturated polyester resin to 120-130 ℃, adding 3-4 parts by mass of antioxidant and 20-25 parts by mass of non-crosslinked silicone rubber particles, stirring for 30-45min, adding diisocyanate and chain extender while stirring until the power of a stirring motor rises by 2 times, stopping stirring, and discharging to obtain a polyurethane mixture;

(3) and (3) extrusion molding, which comprises the following steps:

extruding the polyurethane mixture into sheet PU leather;

the melting point of the unsaturated polyester resin is lower than 110 ℃;

the silicon rubber particles comprise the following components in parts by mass:

100 parts of silicon rubber;

8-10 parts of a cross-linking agent;

1.5-2 parts of foaming agent.

2. The carry-on purse of claim 1, wherein: in the step (1), the uncrosslinked silicone rubber is granulated into spherical uncrosslinked silicone rubber particles.

3. The carry-on purse of claim 1, wherein: the unsaturated polyester resin is prepared by polycondensation of hydroxyl-terminated polybutadiene and adipic acid.

4. The carry-on purse of claim 1, wherein: the foaming agent is a solid foaming agent.

5. The carry-on purse of claim 4, wherein: the foaming agent is carbonate.

6. The carry-on purse according to any one of claims 1-5, wherein: in the step (3), the polyurethane mixture is extruded into the sheet-shaped PU leather, and then is cooled by cooling water with the temperature of below 15 ℃.

7. The carry-on purse of claim 6, wherein: and (4) air-drying the PU leather cooled in the step (3), and then coating a water-based matte finishing agent.

8. The carry-on purse of claim 7, wherein: the water-based matte finishing agent comprises the following components in parts by weight:

25 parts of waterborne polyurethane;

55-65 parts of pure water;

5-8 parts of an organic silicon hand feeling agent;

1-3 parts of a leveling agent;

0.2-0.4 part of defoaming agent;

3-5 parts of a flatting agent;

3-5 parts of lotus leaf powder;

the waterborne polyurethane is self-crosslinking waterborne polyurethane.

9. The carry-on purse of claim 8, wherein: the preparation method of the water-based matte finishing agent comprises the following steps:

(1) adding waterborne polyurethane into pure water, and stirring uniformly to form a waterborne polyurethane solution;

(2) adding an organic silicon hand feeling agent, a flatting agent, a defoaming agent and a flatting agent into the aqueous polyurethane solution, and uniformly stirring to form a premix;

(3) adding lotus leaf powder into the premix, and uniformly stirring to form the aqueous matte finishing agent.

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