Nanocrystalline cellulose (NCC) composite waterborne epoxy resin and preparation method thereof

Abstract

The invention discloses nanocrystalline cellulose (NCC) composite waterborne epoxy resin and a preparation method thereof. The preparation method comprises the following steps: directly adding NCC aqueous suspension into waterborne epoxy resin by adopting stirring and ultrasonic oscillation methods, and cross-linking with an amine curing agent for solidifying to obtain a NCC composite waterborne epoxy resin polymer. The manufacturing method of a composite system is simple and convenient, and NCC can be uniformly and stably dispersed in the waterborne epoxy resin without surface modification and drying. According to the preparation method, intermolecular hydrogen bonds are generated in a cross-linked network of active hydroxyl on the surface of the NCC and the epoxy resin, so that the interaction of the NCC and a resin substrate interface is enhanced and the performance of the composite material can be effectively improved. When the additive amount of the NCC is 8% by mass of the resin, the tensile modulus of the composite polymer is increased by 171%, the tensile strength is enhanced by 115%, and the storage modulus is increased by 438%.

Description

technical field

[0001] The invention relates to a nano-microcrystalline cellulose (NCC) composite water-based epoxy resin and a preparation method thereof. Background technique

[0002] Waterborne epoxy resin systems are mainly used as coatings and adhesives in industrial and civil fields. With the substantial increase in demand in the field of water-based coatings and adhesives, its development prospects are very broad. As early as the 1970s, the development of water-based epoxy resin systems began abroad, and many products have entered the practical stage, and their performance is close to the level of solvent-based epoxy resins. Waterborne epoxy coatings have many advantages such as low VOC content, less odor, safe use, and water cleanability, making them attractive in industry and commerce. The water-based epoxy resin system is composed of a water-based epoxy resin component containing an epoxy group and an amine curing agent component containing an amine group. Both c...

Examples

Embodiment 1

[0026] Example 1: The amount of NCC added is 0.5% of the total mass of the solid resin (water-based epoxy resin and amine curing agent)

[0027] Add 0.6033g of NCC aqueous suspension (3% by mass) to 5.00g of water-based epoxy resin (50% by mass of solid content), stir evenly, and then add 2.80g of amine curing agent (40% by mass of solid content) , Mix evenly, add 7.84g water to dilute, coat the film on the polytetrafluoroethylene plate, put it at room temperature for 2 days, and then bake it in a 90℃ oven for 4h to measure the properties of the composite polymer paint film. The composite product has a tensile modulus of 538.3MPa (25°C), a tensile strength of 9.81MPa (25°C), an elongation at break of 2.54% (25°C), and a storage modulus of 1.074MPa (70°C).

Embodiment 2

[0028] Example 2: The amount of NCC added is 1% of the total mass of the solid resin

[0029] Add 1.207g NCC water suspension (mass percent concentration 3%) to 5.00g water-based epoxy resin (mass percent solid content 50%), ultrasonically vibrate for 20min, then add 2.80g amine curing agent (mass percent solid content 40%) ), mix evenly, add 7.32g of water to dilute, coat the film on the polytetrafluoroethylene plate, put it at room temperature for 2 days, and then bake it in a 90℃ oven for 4h to measure the performance of the composite polymer paint film. The composite product has a tensile modulus of 626.2MPa (25°C), a tensile strength of 11.11MPa (25°C), an elongation at break of 2.46% (25°C), and a storage modulus of 1.362MPa (70°C).

Embodiment 3

[0030] Example 3: The amount of NCC added is 2% of the total mass of the solid resin

[0031] Add 2.413g of NCC aqueous suspension (3% by mass) to 5.00g of water-based epoxy resin (50% by mass of solid content), stir evenly, and then add 2.80g of amine curing agent (40% by mass of solid content) , mixed evenly, diluted with 6.27g of water, coated on a polytetrafluoroethylene plate, placed at room temperature for 2 days, and then dried in an oven at 90 °C for 4 hours to measure the properties of the composite polymer paint film. The composite product has a tensile modulus of 700.5MPa (25°C), a tensile strength of 12.37MPa (25°C), an elongation at break of 3.21% (25°C), and a storage modulus of 2.206MPa (70°C).

technical field

[0001] The invention relates to a nano-microcrystalline cellulose (NCC) composite water-based epoxy resin and a preparation method thereof. Background technique

[0002] Waterborne epoxy resin systems are mainly used as coatings and adhesives in industrial and civil fields. With the substantial increase in demand in the field of water-based coatings and adhesives, its development prospects are very broad. As early as the 1970s, the development of water-based epoxy resin systems began abroad, and many products have entered the practical stage, and their performance is close to the level of solvent-based epoxy resins. Waterborne epoxy coatings have many advantages such as low VOC content, less odor, safe use, and water cleanability, making them attractive in industry and commerce. The water-based epoxy resin system is composed of a water-based epoxy resin component containing an epoxy group and an amine curing agent component containing an amine group. Both c...

Examples

Embodiment 1

[0026] Example 1: The amount of NCC added is 0.5% of the total mass of the solid resin (water-based epoxy resin and amine curing agent)

[0027] Add 0.6033g of NCC aqueous suspension (3% by mass) to 5.00g of water-based epoxy resin (50% by mass of solid content), stir evenly, and then add 2.80g of amine curing agent (40% by mass of solid content) , Mix evenly, add 7.84g water to dilute, coat the film on the polytetrafluoroethylene plate, put it at room temperature for 2 days, and then bake it in a 90℃ oven for 4h to measure the properties of the composite polymer paint film. The composite product has a tensile modulus of 538.3MPa (25°C), a tensile strength of 9.81MPa (25°C), an elongation at break of 2.54% (25°C), and a storage modulus of 1.074MPa (70°C).

Embodiment 2

[0028] Example 2: The amount of NCC added is 1% of the total mass of the solid resin

[0029] Add 1.207g NCC water suspension (mass percent concentration 3%) to 5.00g water-based epoxy resin (mass percent solid content 50%), ultrasonically vibrate for 20min, then add 2.80g amine curing agent (mass percent solid content 40%) ), mix evenly, add 7.32g of water to dilute, coat the film on the polytetrafluoroethylene plate, put it at room temperature for 2 days, and then bake it in a 90℃ oven for 4h to measure the performance of the composite polymer paint film. The composite product has a tensile modulus of 626.2MPa (25°C), a tensile strength of 11.11MPa (25°C), an elongation at break of 2.46% (25°C), and a storage modulus of 1.362MPa (70°C).

Embodiment 3

[0030] Example 3: The amount of NCC added is 2% of the total mass of the solid resin

[0031] Add 2.413g of NCC aqueous suspension (3% by mass) to 5.00g of water-based epoxy resin (50% by mass of solid content), stir evenly, and then add 2.80g of amine curing agent (40% by mass of solid content) , mixed evenly, diluted with 6.27g of water, coated on a polytetrafluoroethylene plate, placed at room temperature for 2 days, and then dried in an oven at 90 °C for 4 hours to measure the properties of the composite polymer paint film. The composite product has a tensile modulus of 700.5MPa (25°C), a tensile strength of 12.37MPa (25°C), an elongation at break of 3.21% (25°C), and a storage modulus of 2.206MPa (70°C).

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