Low-temperature thermal expansion micro-sphere

Abstract

The invention relates to a low-temperature thermal expansion micro-sphere. The micro-sphere is formed in the mode that a shell formed by polymerizing unsaturated alkene monomers wraps inert hydrocarbons. Each unsaturated alkene monomer is composed of acrylonitrile, acrylics and a vinyl acetate monomer. The total mass of each unsaturated alkene monomer is 100 wt% as the calculation datum, the acrylonitrile accounts for 40-80 wt%, the acrylics accounts for 5-55 wt%, and the vinyl acetate accounts for 1-40 wt%. The defects that pollution is caused easily, the production cost is increased and a micro-sphere can not be foamed easily in the prior art are overcome. The low-temperature thermal expansion micro-sphere does not contain halogen, can be synthesized under the low pressure and even under the normal pressure, has the good foaming ability, and is free from pollution and low in cost.

Description

technical field [0001] The invention relates to a chemical product, in particular to low-temperature heat-expandable microspheres. Background technique [0002] Low-temperature heat-expandable microspheres refer to particles with a core-shell structure formed by encapsulating inert hydrocarbons with a polymer shell. When the microspheres are heated to a certain extent, the polymer shell softens, and the gas pressure generated by the boiling of the hydrocarbon wrapped inside promotes the expansion of the microspheres, and when the heating is stopped, the microspheres remain in the expanded state. [0003] Before the present invention was made, the synthesis of low-temperature thermal expansion microspheres mainly combined the following two methods at present: one was to add more polymer monomers with a lower glass transition temperature, such as vinylidene chloride; the other was to use low-boiling hydrocarbons , such as isobutane. However, the large addition of vinylidene ...

AI Technical Summary

Problems solved by technology

However, the large addition of vinylidene chloride is not only easy to cause pollution, but also not in line with the sustainable development of the current environment-friendly economy

In addition, during the reaction process, a high-pressure container is required and high pressure is applied to reduce the volatilization of low-boiling hydrocarbons, which not only increases the production cost, but also increases the risk in the production process, while low-boiling alkanes are easier to Through the polymer shell, which is not good for microsphere foaming

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