Properties of interpenetrating network polymers

It is difficult to generalize. If one of the two polymers behaves as an elastomer and the other is a hard plastic at room temperature, the IPN formed may be either a reinforced rubber or an impact-resistant plastic, depending on the ratio of the two. And preparation conditions.
The results of electron microscopy studies show that IPN has two continuous phases, forming a complex "cell" structure. The wall of the "cell" and the inside of the "cell" are respectively composed of two kinds of polymers. The size of this "cell" is roughly in the range of 50-100 nanometers. In many cases, there are smaller microstructures in the wall and inside of the "cell", with a size of 10-20 nanometers. This fine structure is obviously caused by the interpenetration of networks, but due to these structures The size of the formed micro-area is much smaller than the wavelength of visible light, so a typical IPN is a transparent material.
IPN has also proved that there are two phases in the dynamic mechanical spectrum, but the glass transition zone of the two phases is shifted and obviously widened, and the damping effect is also increased (especially the increase between the two glass transition zones) More), so IPN has the function of silencing or damping in a wide temperature range. IPN, like other thermosetting materials, cannot be reshaped after cross-linking and curing, which is its disadvantage.