Gel Characteristics of Urea-Formaldehyde Resin under Shear Flow Conditions

Abstract EN

Urea-formaldehyde resin (UFR), one of chemical grouts in which the major ingredients are urea-formaldehyde and resin, is widely used in Chinese coal mines grouting.

The gel characteristics of urea-formaldehyde resin (UFR) chemical grout under static conditions have been studied by many researchers.

However, there is little research carried out on the gel characteristics under shear flow conditions.

In fact, chemical grout like UFR keeps in shear flow conditions before gelling in the grouting process.

In order to investigate the gel characteristics of UFR in shear flow conditions, an apparatus which consists of a magnetic stirrer and a viscometer was established.

Magnetic stirrer was used to shear UFR at different velocity.

Then the changes of UFR viscosity could be recorded by viscometer.

As a result, the gel characteristics were summarized under different shear rates, and a formula of gelling is derived.

The results show that the grouting flow rate influences the gelling time.

Faster flow rates will cause longer gelling time, which means that the time for the grout to gel during the flowing process under shear flow conditions is longer than that under static conditions.