Photo-thermal curing type outdoor waterproof daub for construction and preparation method of photo-thermal curing type outdoor waterproof daub

Abstract

The invention discloses photo-thermal curing type outdoor waterproof daub for construction and a preparation method of the photo-thermal curing type outdoor waterproof daub, and the waterproof daub is prepared from the following raw materials in percentage by weight: 100 to 150 parts of pasty PVC (Polyvinyl Chloride) resin, 30 to 50 parts of coal tar, 20 to 40 parts of liquid asphalt, 15 to 25 parts of 4-vinyl-1-cyclohexene-1, 2-epoxy, 10 to 20 parts of vinyl acetate and 0.5 to 2 parts of thermal initiator. 0.3-1.5 parts of a photoinitiator and 8-12 parts of vinyl chloride-vinyl acetate resin. After the waterproof daub is irradiated by the sun / ultraviolet light, the waterproof daub is rapidly subjected to light curing, meanwhile, heat generated by the sun / ultraviolet light and heat generated by additional heating can initiate heat curing of the waterproof daub, and light and heat dual rapid curing is achieved.

Description

Technical Field

[0001] This invention relates to the field of building waterproofing materials technology, specifically to an outdoor waterproofing mortar with both photothermal curing properties and its preparation method. Background Technology

[0002] Adhesive mortar is a mud-like plastic solid with certain adhesive properties. This type of plastic solid is generally composed of solid or liquid adhesives with adhesive properties and powder fillers with certain functions, and may also contain appropriate pigments and auxiliary materials. There are many types of adhesive mortar, including acid-resistant adhesive mortar, corrosion-resistant adhesive mortar, and waterproof adhesive mortar. Currently, the most widely used type on the market is waterproof adhesive mortar. Waterproof adhesive mortar is widely used in roofing projects of industrial plants and civil buildings with various slopes due to its advantages such as good waterproof effect, convenient construction, non-flowing at high temperatures, good adhesion, and non-brittleness at low temperatures.

[0003] In existing technologies, waterproof sealants mainly rely on DBP (dibutyl phthalate) plasticizer to improve toughness, but DBP suffers from problems such as migration, volatilization, and poor durability. Furthermore, existing waterproof sealants use epoxy resin to enhance strength, but epoxy resin alone has a slow curing speed. Summary of the Invention

[0004] The purpose of this invention is to solve the problems of poor durability and slow curing speed of existing waterproof cementitious adhesives, and to provide an outdoor waterproof mortar that combines photothermal curing and its preparation method.

[0005] To achieve the above objectives, the present invention provides a photothermal curing outdoor waterproof sealant for construction, comprising the following raw materials in weight percentages: 100-150 parts of paste-like PVC resin, 30-50 parts of coal tar, 20-40 parts of liquid asphalt, 15-25 parts of 4-vinyl-1-cyclohexene-1,2-epoxy, 10-20 parts of vinyl acetate, 0.5-2 parts of thermal initiator, 0.3-1.5 parts of photoinitiator, and 8-12 parts of chlorovinyl acetate resin.

[0006] More preferably, the waterproof sealant comprises the following raw materials in weight percentages: 120 parts paste PVC resin, 40 parts coal tar, 30 parts liquid bitumen, 20 parts 4-vinyl-1-cyclohexene-1,2-epoxy, 15 parts vinyl acetate, 1 part thermal initiator, 0.8 parts photoinitiator, and 10 parts chlorovinyl acetate resin.

[0007] More preferably, the thermal initiator is benzoyl peroxide or azobisisobutyronitrile, and the photoinitiator is a thioxanthone photoinitiator. The thioxanthone photoinitiator is 2-isopropylthioxanthone or 2-(N-benzyl)acrylamidothioxanthone.

[0008] More preferably, the liquid asphalt is petroleum liquid asphalt, which has good ductility, low levels of harmful substances, and a viscosity of 100-300 mPa·S at 25°C.

[0009] More preferably, the chloroacetic acid resin is a vinyl chloride-vinyl acetate copolymer.

[0010] This invention also provides a method for preparing the above-mentioned outdoor waterproof mortar with both photothermal and curing properties, comprising the following steps: S1, premix the paste-like PVC resin and coal tar, add liquid asphalt and chlorinated resin and stir to mix; S2, add 4-vinyl-1-cyclohexene-1,2-epoxy, vinyl acetate, thermal initiator and photoinitiator, mix evenly to obtain the outdoor waterproof mortar with both photothermal and curing properties for construction.

[0011] More preferably, the premixing time for the paste-like PVC resin and coal tar is 30-50 minutes, and the mixing time after adding liquid asphalt and chlorinated vinyl resin is 1-2 hours.

[0012] Compared with the prior art, the beneficial effects of the present invention are: (1) The outdoor waterproof mortar prepared by the present invention is a light and heat curing type. After being irradiated by the sun / ultraviolet light, the waterproof mortar of the present invention is rapidly cured by light. At the same time, the heat generated by the sun / ultraviolet light and the heat generated by the additional heating can trigger the thermal curing of the waterproof mortar of the present invention, so as to achieve dual rapid curing by light and heat.

[0013] (2) In this invention, under the action of photoinitiator and thermal initiator, 4-vinyl-1-cyclohexene-1,2-epoxy and vinyl acetate undergo a polymerization reaction to form a bifunctional substance containing ester group and epoxy group. The epoxy group is then further crosslinked and cured with nitrogen / sulfur compounds in coal tar and liquid asphalt, thereby realizing UV + thermal dual curing reaction.

[0014] (3) In this invention, 4-vinyl-1-cyclohexene-1,2-epoxy and vinyl acetate are polymerized to form a bifunctional material containing ester groups and epoxy groups. The ester groups and epoxy groups in the bifunctional material work together to toughen the material. On the one hand, at the structural level, the epoxy groups can crosslink with coal tar and liquid asphalt to form a network structure, thereby improving the toughness of the waterproof sealant. On the other hand, at the molecular level, the ester groups can reduce the interaction forces between PVC molecular chains, improve the plasticity of the paste PVC resin, and enhance the toughness of the waterproof sealant.

[0015] (4) This invention does not require the addition of traditional DBP plasticizer to improve the toughness of waterproof sealant and ensure the durability of waterproof sealant.

[0016] (5) The present invention, combined with infrared heat treatment, enables the waterproof mortar to be rapidly heat-cured within 1-2 minutes, effectively preventing the mortar from dripping. Detailed Implementation

[0017] The technical solution of the present invention will be further described below with reference to the embodiments.

[0018] As described in the background section, existing waterproof sealants mainly rely on DBP plasticizers to improve toughness, but DBP suffers from problems such as migration, volatilization, and poor durability. Furthermore, existing waterproof sealants use epoxy resin to enhance strength, but epoxy resin alone has a slow curing speed.

[0019] To address the aforementioned problems, this invention provides a photothermal curing outdoor waterproof sealant for construction, comprising the following raw materials by weight percentage: 100-150 parts of paste-like PVC resin, 30-50 parts of coal tar, 20-40 parts of liquid asphalt, 15-25 parts of 4-vinyl-1-cyclohexene-1,2-epoxy, 10-20 parts of vinyl acetate, 0.5-2 parts of thermal initiator, 0.3-1.5 parts of photoinitiator, and 8-12 parts of chloroacetic acid resin. This invention achieves rapid curing of the waterproof sealant through dual curing via photoinitiator and thermal initiator. In this invention, under the action of a photoinitiator and / or a thermal initiator, the waterproof sealant undergoes a polymerization reaction between 4-vinyl-1-cyclohexene-1,2-epoxy and vinyl acetate after exposure to sunlight / ultraviolet light and / or heating, forming a bifunctional substance containing ester and epoxy groups. The reaction formula is as follows: Where n ranges from 5 to 10, and m ranges from 10 to 20.

[0020] Furthermore, the ester and epoxy groups in the above-mentioned products can synergistically toughen the mortar. On the one hand, at the structural level, the epoxy groups can subsequently cross-link and solidify with nitrogen / sulfur compounds in coal tar and liquid asphalt to form a cross-linked network structure, thereby improving the toughness of the waterproof mortar. On the other hand, at the molecular level, the ester groups can reduce the intermolecular forces of PVC, improve the plasticity of the paste-like PVC resin, and enhance the toughness of the waterproof mortar. The principle is as follows: (1) Structural level The waterproof sealant of this invention does not react at room temperature and can be stably sealed and stored. Under construction conditions (light / heat conditions), the photoinitiator / thermal initiator generates free radicals after being exposed to light / heat, which initiates the polymerization reaction of 4-vinyl-1-cyclohexene-1,2-epoxy with vinyl acetate. At the same time, the sulfur contained in the photoinitiator itself and the sulfur and nitrogen contained in the liquid asphalt initiate the ring-opening of the epoxy groups, forming CS, SS, CSS, CN crosslinks, forming a crosslinked network structure, which improves the tensile strength and toughness of the waterproof sealant.

[0021] (2) Molecular level The principle by which ester groups improve the toughness of paste-like PVC resin is as follows: Pure PVC chains are tightly stacked together by intermolecular forces, and the chain segments can hardly move. Therefore, pure PVC particles are usually hard and brittle, lacking toughness. When ester-based materials are added, the polarity of the ester groups (-COO-) allows them to insert between the polar PVC chain segments, reducing the intermolecular forces and enabling the PVC chain segments to move. This reduces the brittleness of the PVC particles, improves their toughness, and enhances the toughness of the waterproof sealant.

[0022] Meanwhile, the ester group is obtained by polymerization of 4-vinyl-1-cyclohexene-1,2-epoxy and vinyl acetate, which eliminates the need to add DBP plasticizer (dibutyl phthalate) to improve the toughness of the waterproof sealant, avoids the migration and volatilization of DBP plasticizer, improves the durability of the waterproof sealant, and ensures the adhesion performance between the waterproof sealant and the substrate.

[0023] In some embodiments, the photoinitiator is a thioxanthone photoinitiator, such as 2-isopropylthioxanthone or 2-(N-benzyl)acrylamidothioxanthone.

[0024] In some embodiments, the thermal initiator is benzoyl peroxide or azobisisobutyronitrile.

[0025] In some embodiments, the chloroacetic acid resin is a vinyl chloride-vinyl acetate copolymer with a vinyl acetate content of 5-15 wt%. This chloroacetic acid resin enhances the adhesion strength to the substrate through carboxyl polar groups (measured adhesion strength ≥ 1.5 MPa).

[0026] The following description is based on specific embodiments. Unless otherwise stated, the raw materials and reagents used in the embodiments of the present invention are conventionally purchased raw materials and reagents.

[0027] Example 1 This embodiment provides a photothermal curing outdoor waterproof mortar for construction, comprising the following raw materials by weight percentage: 120 parts of paste-like PVC resin P450 (purchased from Shandong Xuxiang Chemical Co., Ltd.), 40 parts of coal tar, 30 parts of petroleum liquid asphalt (purchased from Hebei Tanjiu Energy Technology Co., Ltd.), 20 parts of 4-vinyl-1-cyclohexene-1,2-epoxy (purchased from Ba Shifu (Shanghai) Biomedical Technology Co., Ltd.), 15 parts of vinyl acetate (purchased from Wanwei Group), 1 part of thermal initiator (benzoyl peroxide, purchased from Taizhou Haixiang Chemical Co., Ltd.), 0.8 parts of photoinitiator (2-isopropylthioxanthone, purchased from Guangzhou Yuanda New Materials Co., Ltd.), and 10 parts of chloroacetic acid resin (purchased from Foshan Shangjin Chengzhan New Materials Technology Co., Ltd. (VMCH-1)).

[0028] The preparation method of this waterproof sealant is as follows: (1) Premix the paste PVC resin and coal tar at room temperature for 30-50 minutes. The reason for premixing the paste PVC resin and coal tar first is that the paste PVC resin particles are prone to agglomeration. Premixing it with coal tar first can utilize the good wetting and penetrating properties of coal tar to help the PVC particles disperse initially and avoid the formation of "coated clumps" when liquid asphalt is added later.

[0029] (2) Add petroleum liquid asphalt and chlorinated vinyl resin, and stir and mix at room temperature for 1-2 hours; (3) Add 4-vinyl-1-cyclohexene-1,2-epoxy, vinyl acetate, thermal initiator and photoinitiator, mix evenly and then discharge.

[0030] After infrared heat treatment (1000W-5000W), the waterproof sealant will rapidly pre-cur within 1-2 minutes. Under natural light or ultraviolet light irradiation (UV intensity ≥30mW / cm²) at 25 degrees Celsius, the waterproof sealant will be fully cured in 3 days. In actual construction, curing time may vary slightly due to weather conditions.

[0031] Example 2 The difference between this embodiment and Example 1 is that the weight percentage of 4-vinyl-1-cyclohexene-1,2-epoxy is 15 parts.

[0032] Example 3 The difference between this embodiment and Embodiment 1 is that the weight percentage of coal tar is 30 parts.

[0033] Example 4 The difference between this embodiment and Embodiment 1 is that the weight percentage of chloroacetic acid resin is 8 parts.

[0034] The various properties of the outdoor waterproof mortar with both photothermal curing properties prepared in Examples 1-4 of this invention were tested. The results showed that the waterproof mortar has excellent tensile strength, bonding strength and heat resistance.

[0035] The tensile strength of Example 1 reached 8.5 MPa, which is 40% higher than that of traditional waterproof sealant; the bonding strength reached 1.8 MPa, meeting the GB / T23445-2019 Type I standard, and its bonding strength remained unchanged after 3 months; heat resistance: the sample obtained by curing Example 1 was placed in an 80℃ oven for 168 hours without flowing, and passed the JC / T1067-2008 test.

[0036] The tensile strength of Example 2 reached 5 MPa and the bond strength reached 1 MPa, meeting the GB / T23445-2019 Type I standard. The bond strength was tested after 3 months and remained unchanged. Heat resistance: the sample obtained by curing Example 2 was placed in an 80℃ oven for 168 hours without flowing and passed the JC / T1067-2008 test.

[0037] The tensile strength of Example 3 reached 5.2 MPa and the bond strength reached 1 MPa, meeting the GB / T23445-2019 Type I standard. The bond strength was tested after 3 months and remained unchanged. The sample obtained by curing Example 3 was placed in an 80℃ oven for 168 hours and did not flow, passing the JC / T1067-2008 test.

[0038] The tensile strength of Example 4 reached 7.8 MPa and the bond strength reached 0.5 MPa, barely meeting the GB / T23445-2019 Type I standard. After 3 months, the bond strength remained unchanged. The sample obtained by curing Example 4 was placed in an 80℃ oven for 168 hours without flowing and passed the JC / T1067-2008 test.

[0039] In summary, this invention provides a photothermal curing outdoor waterproof sealant for construction, comprising the following raw materials by weight percentage: 100-150 parts of paste-like PVC resin, 30-50 parts of coal tar, 20-40 parts of liquid asphalt, 15-25 parts of 4-vinyl-1-cyclohexene-1,2-epoxy, 10-20 parts of vinyl acetate, 0.5-2 parts of thermal initiator, 0.3-1.5 parts of photoinitiator, and 8-12 parts of chloroacetic acid resin. Under the action of the photoinitiator and thermal initiator, 4-vinyl-1-cyclohexene-1,2-epoxy reacts with vinyl acetate to form a bifunctional substance containing ester and epoxy groups. These epoxy groups are subsequently cross-linked and cured with nitrogen / sulfur compounds in the coal tar and liquid asphalt, thereby achieving a UV + thermal dual-curing reaction. Furthermore, this invention eliminates the need to add DBP plasticizer (dibutyl phthalate) to improve the toughness of the waterproof sealant, avoids the migration and volatilization of plasticizer, enhances the durability of the waterproof sealant, and provides excellent stability in the adhesion between the waterproof sealant and the substrate.

[0040] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A type of outdoor waterproof mortar with both photothermal and curing properties for construction, characterized in that, The raw materials include the following weight percentages: 100-150 parts of paste PVC resin, 30-50 parts of coal tar, 20-40 parts of liquid pitch, 15-25 parts of 4-vinyl-1-cyclohexene-1,2-epoxide, 10-20 parts of vinyl acetate, 0.5-2 parts of thermal initiator, 0.3-1.5 parts of photoinitiator, and 8-12 parts of chlorovinyl resin.

2. The construction light and heat-cured outdoor waterproof mastic according to claim 1, wherein The raw materials include the following weight percentages: 120 parts of paste PVC resin, 40 parts of coal tar, 30 parts of liquid pitch, 20 parts of 4-vinyl-1-cyclohexene-1,2-epoxide, 15 parts of vinyl acetate, 1 part of thermal initiator, 0.8 parts of photoinitiator, and 10 parts of chlorovinyl resin.

3. The construction light-heat dual-curing outdoor waterproof mastic of claim 1, wherein, The thermal initiator is benzoyl peroxide or azobisisobutyronitrile.

4. The construction light-heat dual-curing outdoor waterproof mastic of claim 1, wherein, The photoinitiator is a thioxanthone photoinitiator.

5. The construction light-heat dual-curing outdoor waterproof mastic of claim 4, wherein the construction light-heat dual-curing outdoor waterproof mastic is characterized by, The thioxanthone photoinitiator is 2-isopropyl thioxanthone or 2-(N-benzyl) acrylamide thioxanthone.

6. The construction light-heat dual-curing outdoor waterproof mastic of claim 1, wherein, The liquid pitch is petroleum liquid pitch.

7. The construction light-heat dual-curing outdoor waterproof mastic of claim 6, wherein the construction light-heat dual-curing outdoor waterproof mastic is characterized by, The viscosity of the petroleum liquid pitch is 100-300 mpa·S.

8. The construction light-heat dual-curing outdoor waterproof mastic of claim 1, wherein, The chlorovinyl resin is a chloroethylene-vinyl acetate copolymer.

9. A method for producing the constructional light-heat dual-curing type outdoor waterproof mastic according to any one of claims 1 to 8, characterized by, The method includes the following steps: S1, premixing the paste PVC resin and coal tar, adding the liquid pitch and chlorovinyl resin and stirring to mix; S2, adding 4-vinyl-1-cyclohexene-1,2-epoxide, vinyl acetate, thermal initiator, and photoinitiator, and uniformly mixing to obtain the construction light-heat combined curing type outdoor waterproof mastic.

10. The construction light-heat dual-curing outdoor waterproof mastic of claim 9, wherein the construction light-heat dual-curing outdoor waterproof mastic is characterized by, In step S1, the premixing time of the paste PVC resin and coal tar is 30-50 minutes, and the stirring and mixing time after adding the liquid pitch and chlorovinyl resin is 1-2 hours.

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