CN117535978A

CN117535978A - Artificial leather material based on plant residue waste utilization and preparation method thereof

Info

Publication number: CN117535978A
Application number: CN202311593528.XA
Authority: CN
Inventors: 董贺翔; 马頔; 宋云颖; 杨童; 朱超
Original assignee: Xinji Baolong Technology Co ltd
Current assignee: Xinji Baolong Technology Co ltd
Priority date: 2023-11-27
Filing date: 2023-11-27
Publication date: 2024-02-09
Anticipated expiration: 2043-11-27
Also published as: CN117535978B

Abstract

The application relates to the technical field of artificial leather preparation, and particularly discloses an artificial leather material based on plant residue waste utilization and a preparation method thereof. The artificial leather material comprises the following raw materials in parts by weight: 20-30 parts of pretreated plant residues, 10-15 parts of aqueous polyurethane emulsion, 10-30 parts of modified emulsion, 2-4 parts of silicone oil and 3-5 parts of cross-linking agent; the modified latex emulsion is obtained by modifying latex through epoxy. The artificial leather material has the advantages of remarkably excellent air permeability and mechanical properties meeting the use requirements.

Description

Artificial leather material based on plant residue waste utilization and preparation method thereof

Technical Field

The application relates to the technical field of artificial leather preparation, in particular to an artificial leather material based on plant residue waste utilization and a preparation method thereof.

Background

With the improvement of environmental awareness, the problems of non-degradation and environmental pollution of the traditional PVC and PU artificial leather are more and more concerned. The preparation of artificial leather by utilizing natural plant raw material residues has important significance.

The plant residues contain more cellulose, lignin and the like, and if the solid residues can be effectively utilized, the production cost of the artificial leather can be reduced, and the problem of environmental pollution caused by the artificial leather can be solved to a certain extent. However, when plant residues are directly used, there is a problem that the artificial leather prepared is not excellent in properties, such as breathability of the artificial leather.

Therefore, it is necessary to provide a method for producing artificial leather using plant residues as a raw material, which is excellent in air permeability and has a certain mechanical property, and an artificial leather.

Disclosure of Invention

In order to improve the air permeability of artificial leather prepared by taking plant residues as raw materials, the application provides an artificial leather material based on plant residue waste utilization and a preparation method thereof.

In a first aspect, the present application provides an artificial leather material based on plant residue waste utilization, which adopts the following technical scheme:

an artificial leather material based on plant residue waste utilization comprises the following raw materials in parts by weight:

20-30 parts of pretreated plant residues, 10-15 parts of aqueous polyurethane emulsion, 10-30 parts of modified emulsion, 2-4 parts of silicone oil and 3-5 parts of cross-linking agent;

the modified latex emulsion is obtained by modifying latex through epoxy.

Through adopting above-mentioned technical scheme, this application is through modifying latex through epoxy, and its effect lies in: 1. after the epoxy is modified, the latex molecules contain more active groups so as to obviously improve the binding activity and the binding stability of the pretreated plant residues and the modified latex; 2. after the epoxy modification, the steric hindrance of the latex molecules is obviously increased, and after the latex molecules are combined with the pretreated plant residues, the amount of molecules such as cellulose and the like combined on unit molecules is reduced, so that the combination stability is higher; 3. after the epoxy modification, the steric hindrance of the latex molecules is obviously increased, so that the air permeability of the prepared artificial leather material is obviously improved.

In the present application, plant residues refer to residues of various plants after various treatments; any plant containing plant cellulose, lignin, etc. may be selected; the treatment method may be crushing, reagent treatment (acid treatment, alkali treatment, etc.), plant extract extraction (e.g. tannin, protein, polysaccharide, etc.) etc.

Optionally, the plant residue is plant residue after tara tannin extraction.

Tara is also named as tara, thorn bean and the like, and is a evergreen thorn shrub or small arbor. Tara has high utilization value because it is rich in tannin. The waste residue produced after extraction of tara tannins is also called an industrial waste residue. According to the scheme, the waste residues after extraction of the tara tannin are fully utilized, and the biodegradable artificial leather product is prepared.

Optionally, the preparation method of the modified latex emulsion comprises the following steps:

step I, mixing rubber latex and an epoxy reagent to obtain a premix; wherein the addition amount of the epoxy agent is 0.5-1.2% of the weight of the rubber latex;

and II, adding an emulsifier into the premix, adjusting the pH value to 9-11, and performing an emulsification reaction to obtain the modified emulsion.

By adopting the technical scheme, the epoxy agent is mixed with the rubber latex in proper quantity for reaction, so that the artificial leather material with excellent air permeability is obtained. The addition amount of the epoxy agent is too small, so that the air permeability of the artificial leather material is affected; the mechanical properties of the artificial leather material are affected by excessive addition of the epoxy agent.

Optionally, the epoxy agent is selected from any one or more of ethylene oxide modified sodium thiosulfate, epichlorohydrin, peroxide and peracid; preferably, the epoxy agent is selected from any one or more of ethylene oxide modified sodium thiosulfate and epichlorohydrin.

Optionally, the peroxide is selected from any one or more of benzoyl peroxide and caproyl peroxide. Further optionally, the peracid is selected from any one or more of oxalic acid and trifluoro peracetic acid.

The main advantages of the ethylene oxide modified sodium thiosulfate are: the reaction condition is mild, the generated byproducts are few, the epoxidation efficiency is high, and the operation is relatively simple. Other epoxidation reagents may have severe reaction conditions or require catalysts and produce more byproducts. 2. If a replacement is required, epichlorohydrin is recommended because it has the closest effect on the epoxidation modification reaction with ethylene oxide.

Optionally, the emulsification in the step II is accompanied by stirring, the stirring speed is 300-500rpm, and the stirring time is 30-60min. Optionally, the emulsification is normal temperature emulsification, and the temperature is 25-35 ℃.

Optionally, the addition amount of the emulsifier is 0.6-0.9% of the weight of the premix.

Optionally, the emulsifier is selected from any one or more of methylcellulose, guar gum, gum arabic, tannin, and phospholipid; further optionally, the phospholipid is soybean phospholipid.

Optionally, the particle size of the latex particles in the modified latex emulsion is 100-500nm.

Optionally, the preparation method of the pretreated plant residues comprises the following steps:

step (1), dispersing and homogenizing plant residues to obtain residue particles;

step (2), soaking the residue particles in alkali liquor, reacting, and carrying out microwave treatment to obtain refined residues;

and (3) washing and drying the refined residues to obtain the pretreated plant residues.

By adopting the technical scheme, the dispersing and homogenizing operation in the step (1) can loosen the structures of the cellulose and lignin parts wrapped by the polysaccharide, is convenient for exposing chemical functional groups in the subsequent treatment process and is beneficial to the crosslinking reaction in an emulsifying system in the later stage. In the step (2), the purpose of the alkali treatment is to: the components such as cellulose, lignin and the like in the residues are fully swelled and activated, and more active groups such as hydroxyl and the like are exposed; simultaneously, lignin and aliphatic components in the residues can be removed, cellulose in the residues is purified, and fibers are further refined and the specific surface area of the fibers is increased; the microwave cooperation can obviously improve the reaction rate, so that the piece processing effect is more obvious; the treated residues can form better interfacial bonding force with the aqueous polyurethane and the modified latex, and the dispersibility of the residues in the subsequent blending latex is improved, so that the plant residues react more fully with the aqueous polyurethane and the modified latex, and the bonding force of the plant residues, the aqueous polyurethane and the modified latex is more stable, thereby obviously improving the air permeability of the artificial leather material and ensuring the mechanical property of the artificial leather material.

Optionally, in step (1), the residue particles obtained have a particle size of 150-200 mesh.

Optionally, in step (1), the dispersing includes: dispersing at 10000-15000rpm for 10-20min; the homogenizing comprises: homogenizing under 60-80 Mpa.

By adopting the technical scheme, the plant residues are fully pretreated, so that active groups on the surfaces of the plant residues are fully exposed and the surfaces of the residues are fully activated.

Optionally, in the step (2), the alkali liquor is 0.5-3wt% sodium hydroxide solution; the reaction conditions include: the reaction time is 2-4h, the reaction temperature is 60-80 ℃, and the solid-liquid ratio is 1 (4-5).

Optionally, in step (2), the conditions of the microwave treatment include: the treatment time is 10-15min, the microwave frequency is 2200-2600MHz, and the power is 300-500W.

Optionally, the artificial leather material has a thickness of 0.8-1.2mm.

In a second aspect, the present application provides a preparation method of the artificial leather material based on plant residue waste utilization, which adopts the following technical scheme:

the preparation method of the artificial leather material based on plant residue waste utilization comprises the following steps: step 1, mixing pretreated plant residues, aqueous polyurethane emulsion, modified latex emulsion, silicone oil and a cross-linking agent, and uniformly dispersing to obtain a raw material mixed solution;

step 2, heating the raw material mixed solution, and then carrying out heat preservation reaction to obtain a composite emulsion;

step 3, cooling, homogenizing, adjusting the pH value to 10-11, and uniformly stirring to obtain the artificial leather material emulsion; and step 4, coating the artificial leather material emulsion on a base cloth, and drying to obtain the artificial leather material.

Through adopting the technical scheme, through the reaction of the step 2, isocyanate groups in the aqueous polyurethane undergo polymerization and crosslinking reactions and chemical reactions with carboxyl groups and hydroxyl groups in natural latex, cellulose and the like in residues also participate in the reactions, and a stable three-dimensional network structure is formed under the action of three raw materials, so that the stable composite emulsion is finally prepared. After the composite emulsion is further processed and used for preparing the artificial leather material, the material with obviously improved air permeability is obtained.

Optionally, the step 1 of uniformly dispersing specifically comprises the steps of high-speed homogenization and ultrasonic homogenization;

the conditions of high-speed homogenization include: stirring at 8000-12000rpm for 10-15min;

the conditions of ultrasonic homogenization include: the ultrasonic frequency is 15-25kHz, and the ultrasonic time is 5-10min.

Optionally, the heating temperature in the step 2 is 60-80 ℃, and the heat preservation reaction time is 1-3h.

Optionally, the coating in the step 4 may be one-time coating or multiple-time coating; in the case of multiple coating, each coating is dried after the end of the coating, and the next coating is performed.

Optionally, the coating amount in step 4 is 80-120g/m ² The coating times are 2-3 times.

Optionally, the drying temperature in step 4 is 80-120 ℃.

In summary, the present application has the following beneficial effects:

the application aims at the plant residues, particularly the residues after extraction of tara tannins, and makes waste use, so as to prepare the environment-friendly biodegradable artificial leather material. The material takes residues after tara tannin extraction as raw materials, and then is treated by alkali liquor and microwave cooperation after being dispersed and homogenized so as to fully purify cellulose and expose active groups (hydroxyl, carboxyl and the like) on the surfaces of the residues; the pretreated plant residues are used for preparing an artificial leather material together with modified latex emulsion and aqueous polyurethane emulsion, wherein the modified latex emulsion is subjected to epoxidation modification treatment, and on one hand, the epoxidation modification ensures that the active sites of the latex emulsion are more, and on the other hand, the steric hindrance of latex molecules is larger during reaction, so that the artificial leather material with remarkably excellent air permeability is prepared; in addition, when the product is prepared, isocyanate groups in the aqueous polyurethane undergo polymerization and crosslinking reactions and undergo chemical reactions with carboxyl groups and hydroxyl groups in natural latex, cellulose and lignin in residues also participate in the reactions, and a stable three-dimensional network structure is formed under the interaction of the three components, so that stable composite emulsion is prepared, and excellent air permeability of the obtained artificial leather material is ensured.

Detailed Description

The present application is further described in detail with reference to the following examples, which are specifically described: the following examples, in which no specific conditions are noted, are conducted under conventional conditions or conditions recommended by the manufacturer, and the raw materials used in the following examples are commercially available from ordinary sources except for the specific descriptions.

Preparation example of pretreated plant residue

This embodiment is illustrated by selecting the residue after extraction of tara tannin as an example in the following preparation examples.

Preparation example 1

The preparation method of the residue after pretreatment of the tara tannin extraction comprises the following steps:

and (1) pretreating the residues after the extraction of the tara tannin by a release type high-speed free combat machine (ZRM-120 free combat machine of the Boshi company of Germany), setting the rotating speed to 10000rpm during free combat and the free combat time to 20min so as to crush the residue tissues. Then homogenizing with a Stansted type high pressure homogenizer, setting homogenizing pressure to 60MPa, and performing 3 times of circulation to further reduce and homogenize the residue particle size to obtain 150-200 mesh residue particles.

And (2) soaking the residue particles in 0.5wt% sodium hydroxide solution with a solid-to-liquid ratio of 1:4, and soaking at 80 ℃ for 4 hours. After the reaction, carrying out microwave irradiation treatment on the residues after alkali treatment by using an XYZ-5 type microwave chemical reactor, wherein the specific conditions are as follows: the microwave frequency is 2200MHz, the power is 300W, the treatment time is 15min, and refined residues are obtained;

and (3) filtering the refined residues, removing sodium hydroxide solution, washing with water, and drying. The specific steps of drying are as follows: the drying adopts multistage drying, and hot air heating by steam is adopted to dry the material so as to quickly reduce 80% of water; and then drying by microwaves for 3 hours at the drying temperature of 100 ℃ to obtain the pretreated tara tannin extracted residue for later use, wherein the water content is 10.64wt% and the pretreated plant residue reaches a stable weight.

Preparation example 2

and (1) pretreating the residues after tara tannin extraction by a release type high-speed free combat machine (ZRM-120 free combat machine of Boshi company, germany), wherein the rotation speed is 12000rpm during free combat, and the free combat time is 15min so as to break the residue tissues. Then homogenizing with a Stansted type high pressure homogenizer, setting homogenizing pressure at 70MPa, and performing 3 times of circulation to further reduce and homogenize the residue particle size to obtain 150-200 mesh residue particles.

And (2) soaking the residue particles in 1.5wt% sodium hydroxide solution with a solid-to-liquid ratio of 1:4.5, and soaking at 70 ℃ for 3 hours. After the reaction, carrying out microwave irradiation treatment on the residues after alkali treatment by using an XYZ-5 type microwave chemical reactor, wherein the specific conditions are as follows: the microwave frequency is 2400MHz, the power is 400W, the treatment time is 12min, and the refined residue is obtained.

And (3) filtering the refined residues, removing sodium hydroxide solution, washing with water, and drying. The specific steps of drying are as follows: the drying adopts multistage drying, and hot air heating by steam is adopted to dry the material so as to quickly reduce 85% of water; and then drying by microwaves for 2.5 hours at the drying temperature of 110 ℃ and the water content of 10.02 weight percent, and pretreating plant residues to reach stable weight and pretreating residues after tara tannin extraction for later use.

Preparation example 3

and (1) pretreating the residues after the extraction of the tara tannin by a release type high-speed free combat machine (ZRM-120 free combat machine of the Boshi company of Germany), wherein the rotation speed is 15000rpm during free combat, and the free combat time is 10min so as to break the residue tissues. Then homogenizing with a Stansted type high pressure homogenizer, setting homogenizing pressure at 80MPa, and performing 2 times of circulation to further reduce and homogenize the residue particle size to obtain 150-200 mesh residue particles.

And (2) soaking the residue particles in a 3wt% sodium hydroxide solution with a solid-to-liquid ratio of 1:5, and soaking at 60 ℃ for 2 hours. After the reaction, carrying out microwave irradiation treatment on the residues after alkali treatment by using an XYZ-5 type microwave chemical reactor, wherein the specific conditions are as follows: the microwave frequency is 2600MHz, the power is 500W, the treatment time is 10min, and refined residues are obtained;

and (3) filtering the refined residues, removing sodium hydroxide solution, washing with water, and drying. The specific steps of drying are as follows: the drying adopts multistage drying, and hot air heating by steam is adopted to dry the material so as to quickly reduce 75% of water; and then drying by microwaves for 2 hours at the drying temperature of 120 ℃ and the water content of 12.37 weight percent, and pretreating plant residues to reach stable weight and pretreating residues after tara tannin extraction for later use.

Preparation example of aqueous polyurethane emulsion

Preparation example 1

The preparation method of the aqueous polyurethane emulsion comprises the following steps:

a) Preparing an aqueous polyurethane dispersion with the solid content of 20wt%, adding 0.2wt% of a thickening agent, 0.1wt% of a pH regulator, and stirring at a high speed at a rotating speed of 8000rpm to prepare a uniform aqueous polyurethane premix.

b) Mixing the aqueous polyurethane premix with 0.5 times of water, adding 1wt% of emulsifying agent for emulsification reaction, adjusting the pH value to 8-9, and obtaining the aqueous polyurethane emulsion with the particle size of 100-300nm after high-speed shearing and emulsification at 10000 rpm.

Preparation example 2

a) Preparing an aqueous polyurethane dispersion with the solid content of 25wt%, adding 0.35wt% of a thickening agent, 0.2wt% of a pH regulator, and stirring at a high speed at a rotating speed of 9000rpm to prepare a uniform aqueous polyurethane premix.

b) Mixing the aqueous polyurethane premix with 0.8 times of water, adding 2wt% of emulsifying agent for emulsification reaction, adjusting the pH value to 8-9, and carrying out high-speed shearing emulsification at 13000rpm to obtain the aqueous polyurethane emulsion with the particle size of 100-300 nm.

Preparation example 3

a) Preparing an aqueous polyurethane dispersion with the solid content of 30wt%, adding 0.5wt% of a thickening agent, 0.3wt% of a pH regulator, and stirring at a high speed at a rotating speed of 10000rpm to prepare a uniform aqueous polyurethane premix.

b) Mixing the aqueous polyurethane premix with 1 time of water, adding 3wt% of emulsifying agent for emulsification reaction, adjusting the pH value to 8-9, and carrying out high-speed shearing emulsification at 16000rpm to obtain the aqueous polyurethane emulsion with the particle size of 100-300 nm.

Preparation example of modified latex emulsion

Preparation example 1

The preparation method of the modified latex emulsion comprises the following steps:

and step I, mixing SVR3 type natural rubber latex (a coil grain company) imported by Malaysia with epichlorohydrin, wherein the addition amount of the epichlorohydrin is 0.5 weight percent of the natural rubber latex, and uniformly mixing to obtain the premix.

Step II, adding deionized water and emulsifier guar gum into the premix, wherein the adding amount of the guar gum is 0.6wt% of the premix, the adding amount of the deionized water is 2 times of the weight of the premix, and regulating the pH to 9-11 for emulsification reaction; specifically, the modified emulsion is obtained by stirring at normal temperature and 300rpm for 60min.

Preparation example 2

and step I, mixing SVR3 type natural rubber latex (a coil grain company) imported by Malaysia and ethylene oxide modified sodium thiosulfate (the trade name of Newcol 560 SF) with the addition amount of the ethylene oxide modified sodium thiosulfate being 0.9 weight percent of the natural rubber latex, and uniformly mixing to obtain the premix.

Step II, adding deionized water and an emulsifier methyl cellulose into the premix, wherein the adding amount of the methyl cellulose is 0.8 weight percent of the premix, the adding amount of the deionized water is 2.5 times of the weight of the premix, and adjusting the pH value to 9-11 to carry out an emulsification reaction; specifically, the modified emulsion is obtained by stirring at normal temperature and 400rpm for 45 min.

Preparation example 3

step I, mixing SVR3 type natural rubber latex (a coil grain company) imported by Malaysia and ethylene oxide modified sodium thiosulfate (the trade name is Newcol 560 SF) of which the addition amount is 1.2 weight percent of the natural rubber latex, and uniformly mixing to obtain a premix.

Step II, adding deionized water and an emulsifier methyl cellulose into the premix, wherein the adding amount of the methyl cellulose is 0.9wt% of the premix, the adding amount of the deionized water is 3 times of the weight of the premix, and regulating the pH value to 9-11 for emulsification reaction; specifically, the modified emulsion is obtained by stirring at normal temperature and 500rpm for 30 min.

PREPARATION EXAMPLES 4 to 7

Preparation examples 4 to 7 differ from preparation example 2 in the amount of the epoxy agent added, specifically as follows:

in preparation example 4, the addition amount of the ethylene oxide modified sodium thiosulfate is 0.2 weight percent of the natural rubber latex;

in preparation example 5, the addition amount of the ethylene oxide modified sodium thiosulfate is 0.5 weight percent of the natural rubber latex;

in preparation example 6, the addition amount of the ethylene oxide modified sodium thiosulfate is 1.2 weight percent of the natural rubber latex;

in preparation example 7, the addition amount of the ethylene oxide modified sodium thiosulfate was 1.5% by weight of the natural rubber latex.

Examples

Example 1

An artificial leather material based on plant residue waste utilization, which is prepared from the following raw materials:

200g of residue after extraction of pretreatment tara tannin, 100g of aqueous polyurethane emulsion, 100g of modified emulsion, 20g of SM2140 silicone oil (DuPont company of America), and 30g of zinc oxide cross-linking agent (Mitsubishi company of Japan). The residue after extraction of pretreatment tara tannin is prepared by a preparation example 1 of the residue after extraction of pretreatment tara tannin, the aqueous polyurethane emulsion is prepared by a preparation example 1 of the aqueous polyurethane emulsion, and the modified latex emulsion is prepared by a preparation example 1 of the modified latex emulsion.

The preparation method of the artificial leather material comprises the following steps:

step 1, placing the residues, the aqueous polyurethane emulsion, the modified emulsion, the silicone oil and the zinc oxide cross-linking agent which are obtained after extraction of the pretreatment tara tannin in the amount in a DJR-3 emulsification reaction kettle for mixing, starting heating to 55 ℃ and stirring at a low speed of 1000rpm, starting a high-speed homogenizer after the temperature is stable, specifically selecting a RW20 digital mechanical stirrer (IKA company in Germany), setting the stirring rotating speed to be 8000rpm, and homogenizing at a high speed for 15min to obtain uniform mixed liquid. Then, the mixed solution was subjected to ultrasonic dispersion in a JP120ST ultrasonic homogenizer (Branson Co., switzerland) at a specific ultrasonic frequency of 15kHz and a power of 60% for 10 minutes to uniformly disperse, to finally obtain a raw material mixed solution.

And step 2, heating the raw material mixed solution to 60 ℃ and then carrying out heat preservation reaction for 3 hours to obtain the composite emulsion.

Step 3, cooling the composite emulsion to 45 ℃, adding 0.2wt% of an emulsifying aid Span-80, continuously stirring and homogenizing for 10min, finally adjusting the pH value to 10-11, and uniformly stirring to obtain the artificial leather material emulsion;

step 4, coating the obtained artificial leather material emulsion on a base cloth, and then coating and drying the base cloth, wherein the step comprises the following concrete steps: at 80g/m ² Is then dried at a temperature of 80 ℃; then further at 80g/m ² Is then dried at a temperature of 120 ℃. An artificial leather material having a thickness of 0.84mm was obtained.

Example 2

250g of residue after extraction of pretreatment tara tannin, 120g of aqueous polyurethane emulsion, 200g of modified emulsion, 30g of SM2140 silicone oil (DuPont company of America) and 40g of zinc oxide cross-linking agent (Mitsubishi company of Japan). The residue after extraction of pretreatment tara tannin is prepared by a preparation example 2 of the residue after extraction of pretreatment tara tannin, the aqueous polyurethane emulsion is prepared by a preparation example 2 of the aqueous polyurethane emulsion, and the modified latex emulsion is prepared by a preparation example 2 of the modified latex emulsion.

step 1, placing the residues, the aqueous polyurethane emulsion, the modified emulsion, the silicone oil and the zinc oxide cross-linking agent which are obtained after extraction of the pretreatment tara tannin in the amount in a DJR-3 emulsification reaction kettle for mixing, starting heating to 60 ℃ and stirring at a low speed of 1500rpm, starting a high-speed homogenizer after the temperature is stable, specifically selecting a RW20 digital mechanical stirrer (IKA company in Germany), setting the stirring rotation speed to 10000rpm, and homogenizing at a high speed for 12min to obtain uniform mixed liquid. Then, the mixed solution was subjected to ultrasonic dispersion in a JP120ST ultrasonic homogenizer (Branson Co., switzerland) at a specific ultrasonic frequency of 20kHz and a power of 65% for an ultrasonic treatment time of 8 minutes to uniformly disperse, to finally obtain a raw material mixed solution.

And step 2, heating the raw material mixed solution to 70 ℃, and then carrying out heat preservation reaction for 1.8 hours to obtain the composite emulsion.

Step 3, cooling the composite emulsion to 40 ℃, adding 0.25wt% of an emulsifying aid Span-80, continuously stirring and homogenizing for 12min, finally adjusting the pH value to 10-11, and uniformly stirring to obtain the artificial leather material emulsion;

step 4, coating the obtained artificial leather material emulsion on a base cloth, and then coating and drying the base cloth, wherein the step comprises the following concrete steps: at 100g/m ² Is then dried at a temperature of 120 ℃; then take 100g/m ² Is then dried at a temperature of 120 ℃; finally, the total weight of the mixture is 100g/m ² Is then dried at a temperature of 120 ℃. Finally, the artificial leather material with the thickness of 1.18mm is obtained.

Example 3

300g of residue after extraction of pretreatment tara tannin, 150g of aqueous polyurethane emulsion, 300g of modified emulsion, 40g of SM2140 silicone oil (DuPont company of U.S.) and 50g of zinc oxide cross-linking agent (Mitsubishi company of Japan). The residue after extraction of pretreatment tara tannin is prepared by a preparation example 3 of the residue after extraction of pretreatment tara tannin, the aqueous polyurethane emulsion is prepared by a preparation example 3 of the aqueous polyurethane emulsion, and the modified latex emulsion is prepared by a preparation example 3 of the modified latex emulsion.

step 1, placing the residues, the aqueous polyurethane emulsion, the modified emulsion, the silicone oil and the zinc oxide cross-linking agent which are obtained after extraction of the pretreatment tara tannin in the amount in a DJR-3 emulsification reaction kettle for mixing, starting heating to 65 ℃ and stirring at a low speed of 2000rpm, starting a high-speed homogenizer after the temperature is stable, specifically selecting a RW20 digital mechanical stirrer (IKA company in Germany), setting the stirring rotation speed to 12000rpm, and homogenizing at a high speed for 10min to obtain a uniform mixed solution. Then, the mixed solution was subjected to ultrasonic dispersion in a JP120ST ultrasonic homogenizer (Branson Co., switzerland) at a specific ultrasonic frequency of 25kHz with a power of 55% for a period of 5 minutes to uniformly disperse, to thereby obtain a raw material mixed solution.

And step 2, heating the raw material mixed solution to 80 ℃ and then carrying out heat preservation reaction for 1.0h to obtain the composite emulsion.

And 3, cooling the composite emulsion to 40 ℃, adding 0.30wt% of an emulsifying aid Span-80, continuously stirring and homogenizing for 15min, finally adjusting the pH value to 10-11, and uniformly stirring to obtain the artificial leather material emulsion.

Step 4, coating the obtained artificial leather material emulsion on a base cloth, and then coating and drying the base cloth, wherein the step comprises the following concrete steps: at 120g/m ² Is then dried at a temperature of 120 ℃; then further at 120g/m ² Is then dried at a temperature of 80 ℃. Finally, the artificial leather material with the thickness of 1.04mm is obtained.

Examples 4 to 7

Examples 4-7 differ from example 2 in that the source of the modified latex emulsion is different; the method comprises the following steps: the modified latex emulsion of example 4 was prepared from modified latex emulsion preparation example 4, the modified latex emulsion of example 5 was prepared from modified latex emulsion preparation example 5, the modified latex emulsion of example 6 was prepared from modified latex emulsion preparation example 6, and the modified latex emulsion of example 7 was prepared from modified latex emulsion preparation example 7.

Examples 8 to 9

Examples 8 to 9 differ from example 2 in the amount of modified latex emulsion added; specifically, the amount of the modified latex emulsion in example 8 was 100g, and the amount of the modified latex emulsion in example 9 was 300g.

Comparative example

Comparative examples 1 to 3

Comparative examples 1 to 3 differ from example 2 in the amount of modified latex emulsion added; specifically, the amount of the modified latex emulsion added in comparative example 1 was 0g, the amount of the modified latex emulsion added in comparative example 2 was 50g, and the amount of the modified latex emulsion added in comparative example 3 was 350g.

Comparative example 4

The difference from example 2 is that the modified latex emulsion is replaced with the latex emulsion of equal weight when preparing the artificial leather material, otherwise the same as in example 2.

The preparation method of the emulsion comprises the following steps: deionized water and an emulsifier methyl cellulose are added into SVR3 type natural rubber latex (a dishing company) imported by Malaysia, the addition amount of the methyl cellulose is 0.8wt% of the natural rubber latex, the pH is adjusted to 9-11, and the emulsification reaction is carried out: stirring at 400rpm for 45min at normal temperature to obtain emulsion.

Comparative example 5

The difference from example 2 is that the raw material for the production of artificial leather material does not contain aqueous polyurethane emulsion, otherwise the same as in example 2.

Comparative example 6

The comparative example provides a conventional PU material (i.e., polyurethane artificial leather) of the product model DZ-PU 20.

Performance detection

1. The air permeability of the artificial leather material obtained by detection of the method of polyurethane artificial leather for vamp with reference to QB/T2780-2006, and the wear resistance of the artificial leather material obtained by detection of the method of polyurethane artificial leather for vamp with reference to QB/T2780-2006. The specific results are shown in Table 1.

Table 1 breathability of different artificial leather materials

As can be seen from the data results of table 1, the artificial leather material prepared by the method of the present application has excellent air permeability as compared with the polyurethane artificial leather of comparative example 6. In this scheme, the artificial leather material excellent in air permeability is obtained mainly by modification of the epoxy resin.

The schemes of example 2 and examples 4-7 demonstrate that the relative amounts of ethylene oxide modified sodium thiosulfate and natural rubber are important in preparing the modified latex emulsion: when the addition amount of the ethylene oxide modified sodium thiosulfate is 0.5-1.2wt% of the natural rubber latex, the air permeability of the obtained artificial leather material is relatively better.

Examples 2, examples 8 to 9 and comparative examples 2 to 3 show that when the addition amount of the modified latex emulsion is in the range of 10 to 30 parts by weight (i.e., corresponding to 100 to 300g in the specific examples) in the preparation of an artificial leather material, an artificial leather material excellent in air permeability can be obtained. The addition amount of the modified latex emulsion has a relatively large influence on the air permeability of the artificial leather material, and on the one hand, the air permeability of the artificial leather material is influenced, and on the other hand, the combination stability of the latex emulsion and the pretreated plant residues is also influenced. However, the latex emulsion of comparative example 1 was not modified or the latex emulsion of comparative example 4 was not modified by epoxy, which resulted in a significant decrease in the breathability of the artificial leather material.

In comparative example 5, the absence of addition of aqueous polyurethane in the preparation of the artificial leather material also directly resulted in a decrease in the air permeability of the material. The main reason is that: the aqueous polyurethane provides the artificial leather material with good flexibility and elasticity, and can form a continuous but not completely closed coating on the surface of the artificial leather. Such a coating helps to increase the air pore density of the artificial leather material, thereby improving its breathability. In addition, the waterborne polyurethane has good hydrophilicity, and can absorb surrounding moisture and carry out evaporation, so that the artificial leather can keep good air permeability in a high-moisture environment. In addition, the traditional artificial leather material is prepared from solvent polyurethane, which can lead to airtight innovation and poor air permeability; the waterborne polyurethane is dissolved in water, so that more micropores can be formed in the artificial leather material, and the air permeability of the artificial leather is improved. Thus, the breathability of the artificial leather material prepared from the raw material of comparative example 5 was significantly reduced.

2. The tensile strength of the artificial leather material is detected by a method of QB/T2780-2006 polyurethane artificial leather for shoe uppers, the tearing strength of the artificial leather material is detected by a method of QB/T2780-2006 polyurethane artificial leather for shoe uppers, and the adhesive strength of the artificial leather material is detected by a method of QB/T2780-2006 polyurethane artificial leather for shoe uppers.

TABLE 2 tensile Strength, tear Strength, adhesive Strength and abrasion resistance of different Artificial leather materials

As can be seen from the data in table 2, the artificial leather material obtained in the present application has excellent breathability, a certain abrasion resistance, and more excellent tensile strength, tear strength and adhesive strength, as compared with the material of example 2 and comparative example 6.

In comparison with the results of example 2 and comparative example 1, the addition of the modified latex emulsion in the preparation of the artificial leather material resulted in an artificial leather material having a somewhat reduced tensile strength, tear strength and adhesive strength, but improved abrasion resistance. Without the addition of modified latex emulsion, the artificial leather material is more densified, and thus the above properties may vary. But overall would still have better properties than the polyurethane material of comparative example 6.

When the prepared raw material modified latex emulsion is replaced by the latex emulsion in comparative example 4, the obtained artificial leather material has reduced tensile strength, tearing strength and adhesive strength compared with example 2, but the abrasion resistance is remarkably improved; the reason for the improved wear resistance is that when no epoxy group participates in the reaction, the compactness of the artificial leather material is higher, so that the wear resistance is improved to some extent.

In contrast, when the raw materials for preparing the artificial leather material of comparative example 5 do not contain aqueous polyurethane, not only the breathability of the artificial leather material is directly affected, but also the tensile strength, tear strength and adhesive strength thereof are remarkably reduced. This may be due to the lack of the aqueous polyurethane material, which directly affects the action of the materials, the network structure formed after the reaction, and the binding stability.

The present embodiment is merely illustrative of the present application and is not intended to be limiting, and those skilled in the art, after having read the present specification, may make modifications to the present embodiment without creative contribution as required, but is protected by patent laws within the scope of the claims of the present application.

Claims

1. The artificial leather material based on plant residue waste utilization is characterized by comprising the following raw materials in parts by weight:

the modified latex emulsion is obtained by modifying latex through epoxy.

2. An artificial leather material based on plant residue waste utilization according to claim 1, wherein the preparation method of the modified latex emulsion comprises the steps of:

3. An artificial leather material based on plant residue waste utilization according to claim 2, wherein the epoxy agent is selected from any one or more of ethylene oxide modified sodium thiosulfate, epichlorohydrin, peroxide and peracid; preferably, the epoxy agent is selected from any one or more of ethylene oxide modified sodium thiosulfate and epichlorohydrin.

4. An artificial leather material based on plant residue waste utilization according to claim 2, wherein the emulsifier is added in an amount of 0.6-0.9% by weight of the premix.

5. An artificial leather material based on the waste utilization of plant residues according to claim 1, wherein the preparation method of the pretreated plant residues comprises the following steps:

6. An artificial leather material based on the utilization of plant residue waste according to claim 5, wherein in the step (1), the particle size of the residue particles obtained is 150 to 200 mesh.

7. An artificial leather material based on plant residue waste utilization according to claim 5, wherein in step (2), the conditions of the microwave treatment include: the treatment time is 10-15min, the microwave frequency is 2200-2600MHz, and the power is 300-500W.

8. A method for preparing an artificial leather material based on the utilization of plant residues waste according to any one of claims 1 to 7, wherein the preparation method comprises the steps of:

step 1, mixing pretreated plant residues, aqueous polyurethane emulsion, modified latex emulsion, silicone oil and a cross-linking agent, and uniformly dispersing to obtain a raw material mixed solution;

step 3, cooling, homogenizing, adjusting the pH value to 10-11, and uniformly stirring to obtain the artificial leather material emulsion;

and step 4, coating the artificial leather material emulsion on a base cloth, and drying to obtain the artificial leather material.

9. The method for producing artificial leather material based on plant residue waste utilization according to claim 8, wherein the uniform dispersion in step 1 specifically includes the steps of high-speed homogenization and ultrasonic homogenization;

10. The method for producing artificial leather material based on plant residue waste utilization according to claim 8, wherein the heating temperature in step 2 is 60 to 80 ℃ and the incubation reaction time is 1 to 3 hours.