Waterproof thermal insulation coating and corrugated board

Abstract

The application discloses waterproof thermal insulation coating and corrugated paperboard, the composition of the coating is improved in the scheme, hollow fiber bodies with thermal insulation particles are added in polyether, polyester and other components, the thermal insulation particles are core silica aerogel particles, and the shell is a core-shell configuration of carboxyl modified polystyrene, the thermal insulation performance of the coating is outstanding, and the coating has higher water resistance, toughness and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of paper, in particular to a waterproof thermal insulation coating and corrugated paperboard. BACKGROUND

[0002] Corrugated paper boxes are common commodity carriers that bear and contain commodities during transportation. However, the corrugated paperboard has low toughness and is prone to tearing. In addition, in the transportation of fresh products, ice blocks or other cooling items are usually placed in the box, but the thermal insulation performance of the corrugated paperboard is poor, which cannot effectively preserve the freshness of the products and is prone to rotting and deterioration.

[0003] To solve this problem, some enterprises have developed thermal insulation films made of materials such as polyester and polyether to be fixed on the paperboard. Although these films have certain thermal insulation performance, they still cannot meet the requirements and need to be improved. SUMMARY

[0004] To solve at least one of the above technical defects, the present application provides the following technical solutions:

[0005] The present application discloses a waterproof thermal insulation coating, which comprises the following raw materials by mass:

[0006] 25-35 parts of polyether, 8-14 parts of polyester, 18-24 parts of isocyanate, 6-10 parts of polymer resin, 2-3 parts of coupling agent, 0.2-0.5 parts of catalyst, 0.5-3 parts of crosslinking agent, 0.3-0.6 parts of defoaming agent, and 2-15 parts of hollow fiber body with thermal insulation particles attached, wherein the thermal insulation particles have a configuration with a silica aerogel particle as the core and a carboxyl-modified polystyrene layer as the shell.

[0007] In this scheme, the composition of the coating is improved by adding hollow fiber body with thermal insulation particles attached to the components such as polyether and polyester. The thermal insulation particles have a core-shell configuration with a silica aerogel particle as the core and a carboxyl-modified polystyrene layer as the shell. This coating has outstanding thermal insulation performance and high water resistance and toughness.

[0008] When used, such as coated on the top and bottom surfaces of the paperboard or placed inside the paperboard, the thermal insulation performance of the paperboard is improved, and the box formed by the paperboard has high thermal insulation performance, facilitating the transportation of commodities.

[0009] Further, the preparation of the hollow fiber body with thermal insulation particles attached: the styrene and silica aerogel are processed by emulsion polymerization and microwave heating to form core-shell particles, and the core-shell particles are carboxyl-functionalized to obtain the thermal insulation particles for standby use.

[0010] The fibers are added to the glutaraldehyde solution for crosslinking reaction, and then the standby thermal insulation particles are added for reaction. After filtration, heat treatment, and shearing, the hollow fiber body is formed.

[0011] For the forming of the hollow fiber body, the above forming process is short and low in difficulty, the fiber is crosslinked with glutaraldehyde to form a net structure, then the heat preservation particles are connected to the net body through the functional groups to form the hollow fiber body, and the coating doped with the fiber body has excellent heat insulation performance.

[0012] Further, the initiator, dispersant and silica aerogel are added to the styrene solution, microwave heating and stirring reaction, centrifugal separation, drying to obtain core-shell particles, the core-shell particles are added to the phthalic anhydride solution, stirring and adding catalyst reaction, solid-liquid separation, drying to obtain heat preservation particles, the dispersant helps to improve the uniformity of the material dispersion, and the surface modification of the polystyrene microspheres is easy to operate and low in difficulty.

[0013] Further, the silica aerogel is nanoscale, and the heat preservation particles are micrometer.

[0014] Further, the size of the hollow fiber body: length, width: 0.1-0.2mm, which is convenient for uniform doping in the coating layer.

[0015] Further, the heat preservation coating is prepared by uniformly mixing and stirring the required raw materials, and then heating and reacting, then adding isocyanate and crosslinking agent, adding catalyst after stopping the reaction, and stirring to obtain the heat preservation coating, which is simple in forming process and easy to operate.

[0016] Further, the polyether is polyethylene glycol, the polyester is polybutylene terephthalate, the high polymer resin is epoxy resin, and the crosslinking agent is pentaerythritol.

[0017] The second aspect of the application discloses a corrugated board, the film layer formed by the above coating is connected between the upper and lower paper boards, the film layer formed by the coating is between the upper and lower paper boards, and the upper and lower paper boards are fixed as a whole through the adhesion of the film layer, so that the forming process is simplified.

[0018] Compared with the prior art, the application has the following beneficial effects:

[0019] 1. The hollow fiber body with a new configuration is added in the components such as polyester and polyether, so that the film layer formed by the coating has excellent heat insulation performance, waterproof performance and good toughness.

[0020] 2. The corrugated board is a three-layer structure composed of the upper and lower paper boards connected by the coating film layer in the middle, which is convenient for forming, and the box formed by the corrugated board is convenient for cold transportation. DETAILED DESCRIPTION

[0021] The application will be further described below in combination with specific embodiments.

[0022] In the following preparation examples: polyether is polyethylene glycol (3500), polyester is polybutylene terephthalate (average molecular weight 1500), high polymer resin is epoxy resin (epoxy equivalent weight 190±2g / eq, epoxy content 5100-5200mmol / kg), crosslinking agent is pentaerythritol, coupling agent is KH550, isocyanate MDI, catalyst is dimorpholinyl diethyl ether, defoaming agent is polyoxypropylene glycerol ether, silica aerogel (nanoscale), fibers such as protein fibers, cellulose fibers, wood fibers, etc., micron-sized, etc. In this example, hollow fibers are used as an example to demonstrate.

[0023] Example 1

[0024] In this example, the preparation of a waterproof thermal insulation coating, including the following steps:

[0025] Preparation of hollow fiber body:

[0026] Styrene is washed with sodium hydroxide solution (5%), and after standing for 1h, the lower layer is poured out, deionized water is added and initiators AIBN, PVP-K30, silica aerogel are added, the mass ratio of silica aerogel to styrene is 1:16, the mass ratio of PVP-K30 to styrene is 1:1, the amount of initiator is 1% of the mass of styrene, ultrasonic for 20min, microwave heating (power at 500W, 70℃, 75min) and stirring reaction, after reaction, centrifugal separation, drying to get core-shell particles.

[0027] Add core-shell particles to phthalic anhydride benzene solution, stir and add catalyst aluminum chloride (0.1% of the mass of the particles), react at room temperature for 3h under nitrogen protection, solid-liquid separation, dry to get thermal insulation particles (particle size in 10-100μm).

[0028] Add 100-200μm hollow fibers to glutaraldehyde solution (3%), crosslinking reaction at 60℃ for 1h, then add prepared thermal insulation particles, the mass ratio of thermal insulation particles to hollow fibers is 0.3:1, heat to 65℃ and react for 3h, filter, heat treatment at 75℃, shear the product after heat treatment into a sheet with a length of 0.1-0.2mm, that is, hollow fiber body, the adhesion rate of thermal insulation particles is about 60%.

[0029] Mix polyether 25 parts, polyester 10 parts, high polymer resin 6 parts, coupling agent 2 parts, defoaming agent 0.3 parts, hollow fiber body with thermal insulation particles 2 parts by mass, heat to melt, then heat to 100℃, vacuum dewatering, continue stirring for 30min, cool to 45℃, add crosslinking agent 0.6 parts, isocyanate MDI 20 parts, react for 60min, then detect viscosity up to 1200CPS, add catalyst 0.2 parts, stir and defoam to get thermal insulation coating.

[0030] Preparation of corrugated paperboard:

[0031] The lower paperboard was laid, and then the thermal insulation paint was coated on the lower paperboard (thickness 3 mm), and then the upper paperboard was laid, and the upper and lower paperboards were adhesively fixed as a whole through the intermediate thermal insulation paint.

[0032] Example 2

[0033] In the preparation of a waterproof thermal insulation paint in this example, the difference from Example 1 is that, by mass, 26 parts of polyether, 12 parts of polyester, 7 parts of polymer resin, 2 parts of coupling agent, 0.4 parts of defoaming agent, 4 parts of hollow fiber body having thermal insulation particles attached thereto, 0.8 parts of crosslinking agent, 18 parts of isocyanate MDI, and 0.3 parts of catalyst were used.

[0034] Preparation of corrugated paperboard:

[0035] The lower paperboard was laid, and then the thermal insulation paint was coated on the lower paperboard (thickness 3.5 mm), and then the upper paperboard was laid, and the upper and lower paperboards were adhesively fixed as a whole through the intermediate thermal insulation paint.

[0036] Example 3

[0037] In the preparation of a waterproof thermal insulation paint in this example, the difference from Example 1 is that, by mass, 30 parts of polyether, 14 parts of polyester, 8 parts of polymer resin, 3 parts of coupling agent, 0.6 parts of defoaming agent, 10 parts of hollow fiber body having thermal insulation particles attached thereto, 1.2 parts of crosslinking agent, 18 parts of isocyanate MDI, and 0.3 parts of catalyst were used.

[0038] Preparation of corrugated paperboard:

[0039] The lower paperboard was laid, and then the thermal insulation paint was coated on the lower paperboard (thickness 4 mm), and then the upper paperboard was laid, and the upper and lower paperboards were adhesively fixed as a whole through the intermediate thermal insulation paint.

[0040] Example 4

[0041] In the preparation of a waterproof thermal insulation paint in this example, the difference from Example 1 is that, by mass, 34 parts of polyether, 10 parts of polyester, 8 parts of polymer resin, 2.3 parts of coupling agent, 0.4 parts of defoaming agent, 14 parts of hollow fiber body having thermal insulation particles attached thereto, 0.8 parts of crosslinking agent, 20 parts of isocyanate MDI, and 0.5 parts of catalyst were used.

[0042] Preparation of corrugated paperboard:

[0043] The lower paperboard was laid, and then the thermal insulation paint was coated on the lower paperboard (thickness 2.8 mm), and then the upper paperboard was laid, and the upper and lower paperboards were adhesively fixed as a whole through the intermediate thermal insulation paint.

[0044] Comparative Example 1

[0045] The difference from example 1 is that the thermal insulation particles and the fibers are added separately, and the thermal insulation particles and the fibers are not attached and crosslinked.

[0046] Comparative example 2

[0047] The difference from example 1 is that the thermal insulation particles and the fibers are added separately, and the thermal insulation particles and the fibers are not attached.

[0048] The prepared corrugated paperboard is subjected to heat insulation detection, and the results are shown in Table 1:

[0049] Table 1

[0050] Thermal conductivity W / mk Example 1 0.26 Example 2 0.22 Example 3 0.14 Example 4 0.21 Comparative Example 1 0.36 Comparative Example 2 0.33

[0051] It can be seen that the hollow fibers combined with aerogel particles have obvious improvement in the heat insulation performance of the paperboard under the defined configuration, and the coating layer itself has good waterproof and toughness performance, which can better reinforce the corrugated paperboard and the formed box, etc., and is suitable for the transportation of fresh products.

[0052] The above is only a preferred embodiment of the present application, and the protection scope of the present application is not limited to the above-mentioned examples. Any technical solution falling within the scope of the present application is within the protection scope of the present application. It should be noted that for ordinary technical personnel in the technical field, some improvements and decorations without departing from the principles of the present application are also considered as the protection scope of the present application.

Claims

1. A water repellent thermal insulation coating, characterized by, By mass, comprising the following raw materials: Polyether 25-35 parts, polyester 8-14 parts, isocyanate 18-24 parts, high polymer resin 6-10 parts, coupling agent 2-3 parts, catalyst 0.2-0.5 parts, crosslinking agent 0.5-3 parts, defoaming agent 0.3-0.6 parts, hollow fiber body attached with thermal insulation particles 2-15 parts, wherein the thermal insulation particles have the following configuration: the inner core is silica aerogel particles, and the outer shell is a carboxyl-modified polystyrene layer; Preparation of hollow fiber body attached with thermal insulation particles: core-shell particles are formed by emulsion polymerization and microwave heating process of styrene and silica aerogel, and the core-shell particles are carboxyl-functionalized to obtain the thermal insulation particles, which are prepared as follows: initiator, dispersant and silica aerogel are added to a styrene solution, and the reaction is carried out by microwave heating and stirring, followed by centrifugal separation and drying to obtain core-shell particles, the core-shell particles are added to a phthalic anhydride solution, and the reaction is carried out by stirring and adding catalyst, followed by solid-liquid separation and drying to obtain thermal insulation particles for standby; The fibers are added to a glutaraldehyde solution for crosslinking reaction, and then the standby thermal insulation particles are added for reaction, followed by filtration, heat treatment and shearing to form the hollow fiber body.

2. A water-proof thermal insulation coating as claimed in claim 1, characterized in that: The silica aerogel is nanoscale, and the thermal insulation particles are micrometer scale.

3. A water-proof thermal insulation coating as claimed in claim 1, wherein: The size of the hollow fiber body: length, width: 0.1-0.2mm.

4. A water-proof thermal insulation coating as claimed in claim 1, wherein: Preparation of thermal insulation coating: the required raw materials are mixed and stirred uniformly, and then heated for reaction, followed by addition of isocyanate and crosslinking agent, addition of catalyst after stopping the reaction, and stirring to obtain the thermal insulation coating.

5. A water-proof thermal insulation coating as claimed in claim 1, wherein: The polyether is polyethylene glycol, the polyester is polybutylene terephthalate, the high polymer resin is epoxy resin, and the crosslinking agent is pentaerythritol.

6. A corrugated paperboard characterized by: The film layer formed by the coating of any one of claims 1-5 is connected between the upper and lower paperboards. The polyether is polyethylene glycol, the polyester is polybutylene terephthalate, the high polymer resin is epoxy resin, and the crosslinking agent is pentaerythritol. The film layer formed by the coating of any one of claims 1-5 is connected between the upper and lower paperboards.