Rigid foam plastic opening and closed cell volume percentage determination - Database & Sql Blog Articles

This standard specifies the method for determining the percentage of open cell and closed cell volume of rigid foam. This standard applies to foams containing a plurality of small cells divided by polymer membranes or pore walls, which may be open-celled (communicated) or closed-celled (not in communication) or composites of these types. This standard replaces GB/T10799-1989.
The main changes of this standard compared with GB/T10799-1989 are as follows:
———Test instrument structure and operation method change: GB/T10799-1989 uses the pressure change method and volume expansion method to measure the impermeable volume, the instrument and operation method are different; this standard can only be measured by the volume expansion method. Through the volume.
———Test sample size change: GB/T 10799—1989 The sample size when measuring by volume expansion method is: length × width × thickness (100mm × 30mm × 30mm); in this standard, the standard sample is two cubes. The dimensions are: 2.5 cm x 2.5 cm x 2.5 cm. Another alternative configuration is two cylinders having a cross-sectional size of 6.25 cm2 and a height of 2.5 cm.
———Change in calculation method of open and closed porosity: GB/T10799—1989 is extrapolated from the test data; this standard is directly calculated by the relevant formula.
———Method of correcting the surface cell formed by cutting: At least three sets of samples with different ratios of surface area to geometric volume in GB/T10799-1989, three samples per group, and the apparent opening of the sample The volume percentage is then extrapolated for calibration; in this standard, the two samples are cut three times in parallel with the sides of the cube along the sides of the cube. A total of 16 smaller cubes are created by halving the two cubes, and the exposed surface area and the number of open cells generated during cutting are doubled, and then measured to obtain a correction value.