Preparation Of Paraffin Emulsion And Their Properties

In the wood-based panel industry,wood-based goods have poor stability of wood size and quality due to the plant fiber with water absorption and hygroscopicity.A suitable waterproofing agent is necessary.The molten wax was early used to waterproof the wood.However,the immersion was not uniform and the consumption of wax was large.The paraffin emulsion as a water-proofing agent has advantages of high productivity,smooth coating,fast drying and low energy consumption.In this paper,the stable paraffin emulsion were prepared using a variety of non-ionic surfactant mixture,the water resistance and other properties of the emulsion were investigated.First,Non-ionic paraffin emulsion was prepared with Phase Inversion Emulsification(PIE)method.The emulsifier of A and B were used to prepare the paraffin emulsion.The stability of the emulsion,the particle size and the viscosity were characterized by a highspeed centrifuge,dynamic light scattering and rotational viscometer.The effects of HLB,the emulsifier dosage,emulsification time,emulsification temperature,and shear rate on various properties of paraffin emulsion were investigated.The paraffin emulsion show good performances when the HLB value is 9.5,dosage of emulsifier is 28%,emulsifying time is 40 min,emulsifying temperature is 87 ℃,and the shear rate is 1000 rad/min.As-prepared emulsion exhibits good centrifugal stability,dispersion level 3,viscosity of 25.4 mPa·s,the average particle size of 244.46 nm.The introduction of 6% oxidized polyethylene wax can greatly reduce the amount of emulsifier.When the dosage of emulsifier is 10%,the emulsion shows dispersion level 4,viscosity of 11.1 mPa·s,the average particle size of 509.59 nm.The wooden block absorbs at least 58.691% of water,the string has an expansion rate of 4.748%,the radial expansion rate is 2.789%,and the axial expansion rate is 0.038%.Second,Non-ionic paraffin emulsion was prepared with Phase Inversion Emulsification(PIE)method.The emulsifier of C and D were used to prepare the paraffin emulsion.The stability of the emulsion,the particle size and the viscosity were characterized by high-speed centrifuge,dynamic light scattering and rotational viscometer.The effects of HLB,the emulsifier dosage,emulsification time,emulsification temperature,and shear rate on various properties of paraffin emulsion were investigated.The paraffin emulsion show good performances when the HLB value is 12.2,dosage of emulsifier is 13.5%,emulsifying time is 40 min,emulsifying temperature is 110 ℃,and the shear rate is 1000 rad/min.As-prepared emulsion exhibits good centrifugal stability,dispersion level 4,viscosity of 79.2 mPa·s,the average particle size of 473.89 nm.The wooden block absorbs at least 57.936% of the mass of water,the string has an expansion rate of 4.925%,the radial expansion rate is 1.501%,and the axial expansion rate is 0.032%;Third,emulsifiers were prepared using the four surfactants,As,B,E,and F,The stability of the emulsion,the particle size and the viscosity were characterized by high-speed centrifuge,dynamic light scattering and rotational viscometer.The effects of HLB,the emulsifier dosage,emulsification time,emulsification temperature,and shear rate on various properties of paraffin emulsion were investigated.The paraffin emulsion shows good performances when the HLB value is 11.43,dosage of emulsifier is 10.5%,emulsifying time is 40 min,emulsifying temperature is 87 ℃,and the shear rate is 7000 rad/min As-prepared emulsion exhibits good centrifugal stability,dispersion level 2,viscosity of 46.43 mPa·s,the average particle size of 730.33 nm.The wooden block absorbs at least 57.936% of the mass of water,the string has an expansion rate of 2.807%,the radial expansion rate is 2.616%,and the axial expansion rate is 0.184%;The maximum load is 1.67 kN,the flexural strength is 37.6 mPa,the elastic modulus is 5067.76 mPa.