Abstract:

Animal glue exhibits excellent properties that non- toxic and unharmful, easy to coacervation at room temperature, poor flowing ability and the low compression strength of sand mould, in order to solve the problem which need to be modified. On the condition of alkaline decomposition, glycerol and dextrin is used as modifier of animal glue. The experimental results are given as the graft copolymerization and esterification crosslinking of modifier of glycerol and dextrin onto the animal glue can be carried out. The best ratio of modifier which is got by experiment (mass ratio) is as follow∶Animal glue∶glycerol∶ethanol dextrin=100∶10∶10∶10, and the optimal modification reaction should be performed at 75 ℃ with a reaction time of 90 min.Then measured the modified animal glue binder, surface tension is 26.451 mN/m and the compressive strength reached 3.30 MPa, the mechanism of modification is analyzed by infrared spectrometer, it is considered that there are a reaction happened among the materials. The tests show that glycerol, ethanol and dextrin composite modifiers can reduce animal glue surface tension, improve the surface wettability, and increased compression strength.

Key words: compressive strength, modifier, surface tension, animal glue