阅读说明：本技术 一种有机硅合成革及其制备方法 (Organic silicon synthetic leather and preparation method thereof ) 是由 唐巧云 李彪 蔡秀 于 2020-11-27 设计创作，主要内容包括：本发明提出一种有机硅合成革,其包括依次层叠设置的基层、中间涂层和表面涂层；中间涂层包括有50％-80％直链型二烷基聚硅氧烷、交联成分、催化剂、抑制剂、粘附剂、填料和色膏,所述交联成分含有0.75～1.6％质量份与硅键合的氢原子的有机聚硅氧烷；表面涂层包括20％-60％支链型有机聚硅氧烷、20％-60％的有机聚硅氧烷树脂、交联成分、填料、稀释剂和色膏,所述交联成分含有至少1％但不超过1.6％质量份与硅键合的氢原子的有机聚硅氧烷。本发明还提供了一种有机硅合成革的制备方法,其先在离型纸上涂覆表面涂层,而后固化,再冷却后涂覆中间涂层,覆上基层,辊压贴合,硫化处理,在冷却后剥离离型纸即可得到有机硅合成革,方法简单、制备快捷。(The invention provides organic silicon synthetic leather which comprises a base layer, a middle coating and a surface coating which are sequentially stacked; the intermediate coating comprises 50-80% of straight-chain dialkyl polysiloxane, a crosslinking component, a catalyst, an inhibitor, an adhesive, a filler and color paste, wherein the crosslinking component contains 0.75-1.6% of organopolysiloxane with silicon-bonded hydrogen atoms by mass; the surface coating layer comprises 20% to 60% of a branched organopolysiloxane, 20% to 60% of an organopolysiloxane resin, a crosslinking ingredient containing at least 1% but not more than 1.6% by mass of an organopolysiloxane of silicon-bonded hydrogen atoms, a filler, a diluent, and a color paste. The invention also provides a preparation method of the organic silicon synthetic leather, which comprises the steps of coating a surface coating on the release paper, curing, cooling, coating an intermediate coating, coating a base layer, rolling, laminating, vulcanizing, cooling, and peeling off the release paper to obtain the organic silicon synthetic leather.)

1. The organic silicon synthetic leather is characterized by comprising a base layer, a middle coating and a surface coating which are sequentially stacked;

the intermediate coating comprises the following components: A. 50-80% straight chain dialkyl polysiloxane, wherein each molecule has at least two vinyl groups on average and the molecular weight is 5-15 ten thousand; B. a crosslinking component containing 0.75 to 1.6 mass% of organopolysiloxane of silicon-bonded hydrogen atoms; C. a catalyst; D. an inhibitor; E. an adhesive agent; F. a filler; G. color paste;

the surface coating comprises the following components:A_Ⅰ20% -60% of branched organopolysiloxane containing at least one Q unit and having general formula

Wherein, the substituents represented by R1 are each alkyl, alkenyl, alkynyl; the substituent represented by R2 is alkyl, aryl, alkoxy or acrylate with 1-6 carbon atoms, and n is 500-1500; a. the_Ⅱ20% -60% of organopolysiloxane resin with the general formula M^R1 _aM^R2 _bT^R1/R2 _cQ_dWherein, the substituents represented by R1 are each alkyl, alkenyl, alkynyl, the substituents represented by R2 are alkyl and aryl groups having 1 to 6 carbon atoms, wherein a, b, c, d are all positive numbers, and the conditions a + b + c + d are 1, 0.2 < a + b < 0.45, 0.05 < a < 0.2, 0.25 < b < 0.4, 0 < c < 0.2, 0.65 < (a + b)/d < 0.9; b is_ⅠA crosslinking component containing at least 1% but not more than 1.6% by mass of an organopolysiloxane of silicon-bonded hydrogen atoms; c_ⅠA catalyst; d_ⅠAn inhibitor; e_ⅠA diluent; f_ⅠAnd a filler.

2. A silicone synthetic leather according to claim 1, wherein in the intermediate coating layer, the molecular weight of the linear type dialkylpolysiloxane is 5 to 10 ten thousand.

3. A silicone synthetic leather according to claim 1, wherein in the intermediate coating, the catalyst is a platinum-vinylsiloxane complex, an alcohol-modified chloroplatinic acid, or a platinum-alkyne based complex.

4. A silicone synthetic leather according to claim 1, wherein in the intermediate coating layer, the inhibitor is an alkynol compound, a polyvinyl polysiloxane, an amide compound, or a maleate compound.

5. A silicone synthetic leather according to claim 1, wherein in the intermediate coating layer, the adhesive isZ-6040, KH-570, vinyltrimethoxysilane or trimethoxysilane.

6. A silicone synthetic leather according to claim 1, wherein in the intermediate coating layer, the filler is white carbon black, quartz powder, alumina, iron oxide or calcium carbonate.

7. The organic silicon synthetic leather according to claim 1, wherein in the surface coating, n in the general formula of the branched chain type organic polysiloxane is 800-1500.

8. A silicone synthetic leather according to claim 1, wherein in the surface coating, the filler is ultrafine nylon powder, silica micropowder, quartz powder, or calcium carbonate.

9. The organic silicon synthetic leather according to claim 1, wherein the base layer is a base fabric comprising polyester, spandex, pure cotton or microfiber.

10. The preparation method of the organic silicon synthetic leather is characterized by comprising the following steps:

s1, coating 10-20u of surface coating on the release paper with the lines, and curing for 30-60S at 150 ℃;

s2, after cooling, coating the intermediate coating, then covering the base layer, rolling the base layer by using a roller to be attached to the intermediate coating, and vulcanizing for 5-10 min at the temperature of 150 ℃;

and S3, after cooling, peeling the base layer from the release paper to obtain the organic silicon synthetic leather.

Technical Field

The invention belongs to the field of synthetic leather materials, and particularly relates to organic silicon synthetic leather and a preparation method thereof.

Background

Natural leather is widely used for producing daily necessities by people due to excellent natural characteristics of being soft, firm and wear-resistant, absorbing moisture, ventilating, keeping warm, keeping shape, absorbing sound and reducing noise and the like, but the natural leather is easy to deform when wet, shrinks and hardens when being dried, is easy to mildew and grow black spots, needs maintenance, is expensive, has limited quantity, cannot meet the requirements of people, and simultaneously, people are required to use artificial leather (synthetic leather) to replace the natural leather in order to avoid killing a large number of animals for leather.

Synthetic leather is a plastic product with appearance and hand feeling similar to natural leather and can replace the natural leather. At present, polyvinyl chloride (PVC) and Polyurethane (PU) are mainly used in the synthetic leather industry at home and abroad, PVC artificial leather is light in weight, easy to process, wear-resistant and low in price, but has poor air permeability, low flexibility caused by low-temperature hardening, cracking and poor slip resistance, PU synthetic leather is soft in hand feeling, air permeability and environment-friendly, is preferred as leather clothing, but is not waterproof and not bright and easy to age, and in addition, a large amount of organic solvents are used in the production of PVC artificial leather and PU artificial leather, so that the problem of large amount of environment-friendly pollution is brought. The organic silicon material is a new material mainly connected by a silica bond, and has a series of excellent properties, such as high temperature resistance, low temperature resistance, hydrophobicity, moisture resistance and weather aging resistance, the product is non-toxic and pollution-free, has environment-friendly property, stable colloid property, ensures bright color, excellent color fastness, soft and smooth hand feeling, smoothness, fineness, high elasticity, water resistance and pollution resistance, but the coating strength is far less than that of PU.

Aiming at the problems, a new technical scheme is provided, and the organic silicon synthetic leather with good hand feeling, good stain resistance, scratch resistance and excellent wear resistance and the preparation method thereof are developed.

Disclosure of Invention

In order to overcome the limitation of the prior art, the invention provides organic silicon synthetic leather and a preparation method thereof.

In order to solve the technical problems, the invention adopts the following technical scheme:

an organic silicon synthetic leather comprises a base layer, a middle coating and a surface coating which are sequentially stacked;

the intermediate coating comprises the following components: A. 50-80% straight chain dialkyl polysiloxane, wherein each molecule has at least two vinyl groups on average and the molecular weight is 5-15 ten thousand; B. a crosslinking component containing 0.75 to 1.6 mass% of organopolysiloxane of silicon-bonded hydrogen atoms; C. a catalyst; D. an inhibitor; E. an adhesive agent; F. a filler; G. color paste;

the surface coating comprises the following components: a. the_Ⅰ20% -60% of branched organopolysiloxane containing at least one Q unit and having general formula

Wherein, the substituents represented by R1 are each alkyl, alkenyl, alkynyl; the substituent represented by R2 is alkyl, aryl, alkoxy or acrylate with 1-6 carbon atoms, and n is 500-1500; a. the_Ⅱ20% -60% of organopolysiloxane resin with the general formula M^R1 _aM^R2 _bT^R1/R2 _cQ_dWherein, the substituents represented by R1 are each alkyl, alkenyl, alkynyl, the substituents represented by R2 are alkyl and aryl groups having 1 to 6 carbon atoms, wherein a, b, c, d are all positive numbers, and the conditions a + b + c + d are 1, 0.2 < a + b < 0.45, 0.05 < a < 0.2, 0.25 < b < 0.4, 0 < c < 0.5, 0.65 < (a + b)/d < 0.9; b is_ⅠA crosslinking component containing at least 1% but not more than 1.6% by mass of an organopolysiloxane of silicon-bonded hydrogen atoms; c_ⅠA catalyst; d_ⅠAn inhibitor; e_ⅠA diluent; f_ⅠA filler; g_ⅠAnd color paste.

Preferably, in the intermediate coating layer, the molecular weight of the linear type dialkylpolysiloxane is 5 to 10 ten thousand.

Preferably, in the intermediate coating, the catalyst is a platinum-vinylsiloxane complex, an alcohol-modified chloroplatinic acid, or a platinum-alkyne based complex.

Preferably, in the intermediate coating layer, the inhibitor is an alkynol-based compound, a polyvinyl polysiloxane, an amide compound, or a maleate-based compound.

Preferably, in the intermediate coating, the adhesive isZ-6040, KH-570, vinyltrimethoxysilane or trimethoxysilane.

Preferably, in the intermediate coating, the filler is white carbon black, quartz powder, alumina, iron oxide or calcium carbonate.

Preferably, in the surface coating layer, n in the general formula of the branched organopolysiloxane is 800 to 1500.

Preferably, in the surface coating, the filler is ultrafine nylon powder, silica micropowder, quartz powder or calcium carbonate.

Preferably, the base layer is base cloth and comprises terylene, spandex, pure cotton or microfiber.

A preparation method of organic silicon synthetic leather comprises the following steps:

s1, coating 10-20u of surface coating on the release paper with the lines, and curing for 30-60S at 150 ℃;

s2, after cooling, coating the intermediate coating, then covering the base layer, rolling the base layer by using a roller to be attached to the intermediate coating, and vulcanizing for 5-10 min at the temperature of 150 ℃;

and S3, after cooling, peeling the base layer from the release paper to obtain the organic silicon synthetic leather.

The beneficial effects of the invention are embodied in that:

the organic silicon synthetic leather provided by the invention has good hand feeling (the silica gel has the characteristics of softness, fineness and high elasticity, and the superfine nylon powder enables the hand feeling to be more smooth), good anti-fouling effect (the silica gel has good fouling resistance), ageing resistance (the formed liquid silicone rubber can be used for a long time in the range of-40-200 ℃), and strong scraping resistance (Q unit and M unit in branched silicone oil)^R1 _aM^R2 _bT^R1/R2 _cQ_dThe T and Q units in the organopolysiloxane resin provide a tighter net-shaped cross-linked structure, so that the tearing strength of the coating is obviously improved, and the tackifier in the intermediate coating ensures that the coating and the base material as well as the intermediate coating and the surface coating have good adhesion between layers), and has excellent wear resistance (superfine nylon powder, which enhances the hand feeling of the synthetic leather)The coating has more excellent wear resistance and high elasticity (long linear structure- (R) in each branched chain in branched silicone oil)² ₂SiO)_n–SiR¹R² ₂The provided flexibility enables the coating to have enough elongation and meets the requirement of high elasticity of the synthetic leather), and the like, and the preparation method is simple and rapid.

Detailed Description

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

Various formulations of the intermediate and top coatings are given below, as shown in tables 1 and 2.

In tables 1 and 2, A-1, A-2, A-3, A-4 and A-5 are 50-80% of straight chain type dialkyl polysiloxane in the intermediate coating, wherein

A-1: dimethylpolysiloxane with a viscosity of 5000mPa.s, containing vinyl groups in both the side chain and the ends and a vinyl content of 0.24%;

a-2: dimethylpolysiloxane having a viscosity of 10000mPa.s, containing vinyl groups in both the side chain and the ends and a vinyl content of 0.15%;

a-3: dimethylpolysiloxane with a viscosity of 50000mPa.s, containing vinyl groups in both the side chains and the ends and a vinyl content of 0.1%;

a-4: a dimethylvinyl terminated dimethylpolysiloxane with a vinyl content of 0.08% having a viscosity of 60000 mPa.s;

a-5: a dimethylvinyl-terminated dimethylpolysiloxane having a vinyl content of 0.06% and a viscosity of 100000 mPas.

In tables 1 and 2, B-1, B-2 and B-3 are organopolysiloxanes containing 0.75 to 1.6% by mass of silicon-bonded hydrogen atoms

B-1: 0.5% polyhydrosiloxane with silicon-bonded hydrogen atom content and end-capped with trimethylsiloxy groups, viscosity 20 mpa.s;

b-2: 0.75% of a polyhydrosiloxane containing silicon-bonded hydrogen atoms and terminated with trimethylsiloxy groups, viscosity 50 mpa.s;

b-3: 1.0% polyhydrosiloxane with silicon-bonded hydrogen atom content and end-capped with trimethylsiloxy groups, viscosity 80 mpa.s.

In tables 1 and 2, A_Ⅰ-1、A_Ⅰ-2、A_Ⅰ-3 is from 20% to 60% branched organopolysiloxane in the top coating, wherein

A_Ⅰ-1: a branched polysiloxane having a vinyl content of 1.0%, a viscosity of 20000mpa.s, an average unit formula of n ═ 800;

A_Ⅰ-2: a branched polysiloxane having a vinyl content of 0.08%, a viscosity of 60000mpa.s, and an average unit formula n of 1000;

A_Ⅰ-3: a branched polysiloxane having a vinyl content of 0.06%, a viscosity of 100000mpa.s and an average unit formula n of 1200.

In tables 1 and 2, A_Ⅱ-1、A_Ⅱ-2、A_Ⅱ-3 is 20% to 60% of the organopolysiloxane resin in the surface coating, wherein

A_Ⅱ-1: average unit formula is (ViMe)₂SiO_1/2)_0.087(Me₃SiO_1/2)_0.333(ViSiO_3/2)_0.030(SiO_4/2)_0.550And a vinyl content of 4.5%;

A_Ⅱ-2: average unit formula is (ViMe)₂SiO_1/2)_0.061(Me₃SiO_1/2)_0.359(ViSiO_3/2)_0.030(SiO_4/2)_0.550And a vinyl content of 3.5%;

A_Ⅱ-3: average unit formula is (ViMe)₂SiO_1/2)_0.042(Me₃SiO_1/2)_0.378(ViSiO_3/2)_0.030(SiO_4/2)_0.550And vinyl groups ofThe content is 2.8%;

A_Ⅱ-4: the patent CN103821008A provides a structure R_nSiX_4-nThe hydrolysis prepolymer of the organosilicon monomer mixture has the structure of X (R)₂SiO)_mAnd (3) a block-type silicone resin obtained by condensation polymerization of a linear polysiloxane of X, wherein n is 1, 2, 3, 4, and m is 500.

In tables 1 and 2, B_Ⅰ-1、B_Ⅰ-2 is a crosslinking component of the surface coating, wherein

B_Ⅰ-1: average unit formula (HMe)₂SiO_1/2)_0.92(SiO_4/2) An organohydrogenpolysiloxane having a hydrogen content of 0.75%;

B_Ⅰ-2: average unit formula (HMe)₂SiO_1/2)_2.0(SiO_4/2) An organohydrogenpolysiloxane having a hydrogen content of 1.0%.

TABLE 1 intermediate coat component ratios

TABLE 2 surface coating composition ratios

A plurality of examples and comparative examples are formed by matching a plurality of matching schemes of the intermediate coating and the surface coating in tables 1 and 2, and the organosilicon synthetic leather obtained in the examples and comparative examples is tested, and the relationship between the matching schemes of the intermediate coating and the surface coating and the final test result is analyzed, as shown in tables 3 and 4.

The test method and the judgment standard are as follows:

the test method comprises the following steps:

1. judging hand feeling: placing the palm on the surface of the organic silicon synthetic leather for back and forth friction, and taking OK as dry and smooth hand feeling; the hand feeling is dry and slightly astringent; the hand feeling is cool and unsmooth, and is NG;

2. and (3) anti-fouling test: 3-5 samples of 100 mm. times.200 mm were cut and tested using instant coffee, cola, orange juice according to the protocol Q/JLY J7110614B-2015.

And (4) judging the standard:

level 1-stains are hardly removed, with obvious staining (black spots, etc.);

grade 2-small portion of stain was removed (area less than 50%), sample was significantly changed;

grade 3-most of the stain was removed (area greater than 50%), and the residue was clearly found;

grade 4-most of the stain was removed (area greater than 50%), the specimen was slightly discolored or stained;

grade 5-the stain was completely removed and no stain was found.

3. And (3) wear resistance test: testing Martindale (Martindale) -testing according to the method specified in GB/T13775, and adopting SM-25 wool cloth and load 795g, and performing 100000 times of single test.

And (4) judging the standard:

level 1, the leather surface is seriously abraded and the cloth bottom is obviously exposed;

level 2, the texture of the leather surface is basically ground flat or the texture becomes light and the edge is seriously damaged;

grade 3-clear surface texture, slight edge wear or damage;

grade 4-surface gloss changed, surface grain clear and no wear or damage;

grade 5-the surface texture of the leather is basically unchanged.

The Taber test is carried out according to a method specified in ASTM-D3884, and an H-22 grinding wheel and a single-side load of 750g are adopted for testing.

And (4) judging the standard:

1-500 times of grinding or breaking the leather surface grains;

2-1000 times of grinding or breaking the leather surface grains;

3-1500 times of grinding or breaking the leather surface grains;

4-grade-2000 times of grinding or breaking leather surface grains;

grade 5-more than or equal to 2500 times of grinding or damaging the surface texture of the leather.

4. Scratch resistance test: the test was carried out according to the method specified in SAE J365-2004, with 50 times of 20N weight.

And (4) judging the standard:

level 1-leather surface is obviously damaged and cloth bottom is exposed;

2, the leather surface has obvious scratches and is damaged;

grade 3, the leather surface has obvious scratches and is not damaged;

grade 4, the leather surface is slightly scratched and is not damaged;

grade 5-the leather surface has no scratch and no obvious change.

5. And (3) testing the peeling force: 3-5 samples were taken in the warp and weft directions, respectively, and the dimensions were 150 mm. times.50 mm. One end of each specimen was cut (peel between the top coat and the base fabric) and the peeling was carried out at about 50mm as specified in method B of GB/T8808-1988 at a test speed of 100 + -10 mm/min and was stopped at a peel distance of up to 100mm, and the data was recorded and the average was calculated.

6. And (3) elasticity test: the elastic cloth with the elongation rate of 1000 (%) is used as the base cloth to carry out the test, the synthetic leather is pulled to the elongation rate to be extremely high and then recovered, the test is repeated for 20 times, and whether the coating cracks or does not crack, deform to OK or deform to be good is observed, partial cracks are general, and all cracks are NG.

7. Color fastness: taking a sample wafer with the length multiplied by the width of 140 multiplied by 50mm, using a grinding head with the diameter of 16mm, cotton rubbing cloth, waterproof fine sand paper and the like to carry out dry rubbing test and wet rubbing test (the water content of the rubbing cloth is 95-100%) according to GB/T3920-2008, and evaluating staining by using a gray sample card (which conforms to GB/T251);

and (4) judging the standard:

the gray sample card is divided into 5 grades and 9 grades, the friction color fastness corresponds to the grade number of the color card, 5 grades are the best friction color fastness, 1 grade is the worst friction color fastness, and the like.

8. Folding fastness: sampling was performed as QB/T2706-2005, 6 samples were cut from the grain surface with a die knife as specified in QB/T2707-2005, with the long edge of 3 samples parallel to the ridge line and the long edge of 3 samples perpendicular to the ridge line, and dry testing was performed as specified in QB/T2714-2005.

And (4) judging the standard: whether there is a break or crack.

9. Solvent wiping experiment

1. Alcohol wiping experiment, 150X 150mm sample is poured with 99% alcohol, wiped with 500g weight for 50 circles repeatedly, surface dyeing of white cotton cloth is observed, and samples are cut from the wiped part to test scratch resistance, Martindall and taber

2. Wiping with clear water, namely taking a 150-by-150 mm sample, pouring tap water, repeatedly wiping with a 500-g weight for 50 circles, observing the surface dyeing of white cotton cloth, cutting the sample from the wiped part, and testing scratch resistance, Martindall test and taber test.

TABLE 3 test of synthetic leather made with different intermediate layers and top coats

TABLE 4 test of synthetic leather made with different intermediate layers and top coats

And (4) conclusion: analyzing tables 1, 2, 3, and 4, it can be seen from comparative examples 1, 2, and 3 and comparative examples 4 and 5 that the use of the branched type organopolysiloxane has more excellent scratch resistance and abrasion resistance than the use of the linear type organopolysiloxane; as is clear from comparison of example 3 with comparative example 2, when the hydrogen content of the crosslinking component of the intermediate coating layer is less than 75%, the elasticity becomes remarkably poor; comparing example 3 with comparative example 3, it can be seen that the reduction of fumed silica content results in the performance reduction of the intermediate coating, thereby reducing the peeling force and the folding fastness of the leather; comparing examples 3 and 8 with comparative example 1, it can be seen that the short chain polydimethylsiloxane reduced the elasticity of the intermediate coating; comparing example 3 with comparative example 8, it can be seen that the filler of the surface coating layer has obvious enhancement effect on the scratch resistance and the abrasion resistance of leather; comparing examples 1, 2, 3, 4, 5, 6 with comparative examples 8, 9, it can be seen that the adhesion promoter in the intermediate coating plays a crucial role in the adhesion between the coating and the substrate; comparing examples 1-10 with comparative example 10, it can be seen that, although the block-type silicone resin provided in patent CN103821008A has excellent wear resistance, the cross-linking density is reduced due to the introduction of a straight chain segment into the resin structure, the scratch and wear resistance is obviously reduced after alcohol/clean water wiping, and the use of Q units in the branched silicone oil and T and Q units in the organopolysiloxane resin together provides a more compact cross-linking structure for the whole system, and the effect on the coating is less due to the action of the solvent, thus maintaining excellent scratch and wear resistance.

The above preferred embodiments should be considered as examples of the embodiments of the present application, and technical deductions, substitutions, improvements and the like similar to, similar to or based on the embodiments of the present application should be considered as the protection scope of the present patent.