Alkyl ketene, preparation method and application thereof

Abstract

The invention discloses alkyl ketene, a preparation method and application thereof. The preparation method comprises the following steps: heating up 30 to 70 portions of amine by weight to a temperature of between 55 and 85 DEG C, adding 100 portions of acyl chloride by weight within 0.5 to 2 hours, and reacting continuously after adding the acyl chloride for 0.5 to 3 hours; adding 100 to 200 portions of water of which the temperature is between 70 and 80 DEG C by weight, mixing and then standing the mixture, and removing a salt solution at the bottom layer; adding 100 to 200 portions of water of which the temperature is between 70 and 80 DEG C by weight again, mixing and standing the mixture, and removing the water at the bottom layer; and dehydrating the mixture, filtering the mixture while the mixture is hot, and cooling the filtered mixture to obtain an alkyl ketene dimer. The method uses no solvent, is more environment-friendly and has simple process; and the product has high content of the alkyl ketene dimer, and has good water resisting effect when the product is used as a sizing agent. The obtained alkyl ketene dimer can be used for sizing paper sheets and can greatly improve the Cobb value of the paper sheets and enhance the ring crushing strength of the paper sheets.

Description

technical field

[0001] The invention relates to an alkyl ketene dimer, its preparation method and its application in paper sizing. Background technique

[0002] Alkyl ketene dimer is a kind of wax, and its molecular structure can be represented by the following formula:

[0003]

[0004] R 1 for C 4 ~C 30 Alkyl or C 4 ~C 30 Alkenyl, R 2 for hydrogen or C 1 ~C 8 alkyl.

[0005] The melting point of alkyl ketene dimer is 40-52°C. It is used as a sizing agent for papermaking pulp to make the paper impervious to water. It is used for food packaging paper or other corresponding purposes.

[0006] At present, in the domestic production of synthetic alkyl ketene dimers, the synthesis reaction temperature is lower than the melting point of alkyl ketene dimers, generally around 25°C. At this temperature, the reaction speed is slow, and a long holding time is required. Moreover, the viscosity of the material is high at this temperature. A large amount of toluene solvent n...

Images