Interpenetrating polymer networks, the state of the art

Abstract

Interpenetrating polymer networks are combinations of two crosslinked polymers. Often, they exhibit dual phase continuity, meaning that both phases extend continuously throughout the sample. Recent research on IPNs has shown that both nucleation and spinodal decomposition mechanisms are important in the kinetics of phase separation.If the polymers are almost miscible, a microheterogeneous morphology will develop. Under these conditions, the glass transition of the IPN may be very broad, extending the range between the glass transition of the two homopolymers. Such materials are useful for sound and vibration damping. The loss and storage modulus, and tan δ behavior of polymers and IPNs in the glass transition region were evaluated on a quantitative basis, in order to characterize their damping behavior better. Corrections for background in dynamic mechanical spectroscopy studies will be discussed. The storage modulus of polystyrene at 25°C was selected as a standard. The development of a group contribution analysis of the integral area under the linear loss modulus‐temperature curves, the loss area, LA, is reviewed, and applied to a number of acrylic, styrenic, and vinyl statistical copolymers and IPNs. Each moiety in a polymer is shown to contribute to LA on a simple, additive basis.New research emphasizes the role of morphology and phase continuity in determining LA. The system cross‐poly(vinyl methyl ether)‐inter‐cross‐polystyrene was selected, because its phase diagram in the blend state is well known, and it has become both a model and interesting system to investigate. Midrange IPN compositions exist as two phases at room temperature, as illustrated by dynamic mechanical spectroscopy.

Formation of a Liquid-Crystalline Interpenetrating Poly(ionic liquid) Network Hydrogel

“…Volatiles were removed in vacuo to yield a waxy white solid (4.02 g, 26%). 1 Polymer Synthesis. Poly(1-(10-(acryloyloxy)decyl)-3-methylimidazolium) chloride, poly[AcrC 10 mim þ ][Cl -] (2), was prepared using the procedure previously described.…”

“…Interpenetrating polymer networks (IPNs) consist of two distinct polymer components which are interlaced on a molecular length scale and resist separation due to noncovalent physical entanglement. , IPNs can be prepared by reaction of the constituents simultaneously or sequentially. Sequential IPNs can be formed by first swelling a network polymer after which a second monomer is introduced and polymerized.…”

Applications of Modulated Temperature Differential Scanning Calorimetry to Polymer Blends and Related Systems

“…Most of the papers describe the synthesis and morphological behaviour [98,[101][102][103][104][105][106][107][108][109], status and developments [110,111], properties [112] and industrial applications [113][114][115][116] and self-organisation [117] of IPNs. In recent years, a significantly increasing number of commercial IPN products ranging from false teeth to ion-exchange resins, high impact plastics, thermoplastics, adhesives, vibration damping materials and high temperature alloys have been developed.…”