Local and cooperative molecular mobilities in thermoplastic polymers

Effect of Blending on the Structure of Thermoplastic Interpenetrating Polymer Networks

“…7a) reveal the features already discussed: [4] (i) a small jump at the glass transition temperature T g ffi 227 + 2 K of the amorphous phase of CPU and a broad endothermic process (heat of melting DH m à ¼ 74 + 4 J g 21 ) at the melting temperature T m ¼ 332 K of oligomeric butylene adipate glycol (BAG) microcrystals of CPU and (ii) the usual endothermic peak overlapped to a sudden jump from glassy to rubber-like behavior at T g ffi 359 + 2 K of neat S-b-AA(K þ ). DSC traces of t-IPNs containing 90 and 10 wt.% of CPU (CPU/S-b-AA(K þ ) ¼ 90/10 and 10/90) exhibit, respectively:…”

“…[4,5] Films of thermoplastic CPU/S-b-AA(K þ ) blends having different weight fractions and referred to as t-IPNs, [1,6,7] were prepared by casting from 20%-solutions in dioxane onto Teflon plates and subsequent evacuation to constant weight. In order to avoid undesirable effects due to contamination from absorbed water moisture, [4] the samples were dried at about 330 K under vacuum of 10 24 mbar for 12 h before each run of measurements and then analyzed by maintaining the experimental chamber under a controlled atmosphere of nitrogen. Thermograms were determined by using a Perkin-Elmer Pyris1 differential scanning calorimeter (DSC), calibrated with indium and zinc standards.…”

“…[3] A recent study [4] of the thermal and mechanical properties of one t-IPN based on styrene/acrylic acid block-copolymer (S-b-AA(K þ )) and semicrystalline polyurethane (CPU) gave indications about significant deviations of the studied properties from a simple dilution effect, implying a limited miscibility of the two polymeric components.…”

Effect of Specific Interactions on Structure‐Property Relationships of Thermoplastic IPNs Based on Polyurethane and Styrene‐co‐Acrylic Acid Ionomers

“…Among the various polymer pairs compatibilized by use of ionic interactions, polymer blends based on polyurethanes have received special attention due to their potential applications and academic interest. [7][8][9] Polymer blends of this type can be classified as thermoplastic interpenetrating polymer networks (TIPNs), which are usually formed from two or more physically crosslinked polymers, such as block-copolymers, semicrystalline or ion-containing polymers, where the physical bonds play the role of effective crosslink sites. [10] It is well known that polymer blends of the TIPNs type exhibit lower degree of phase separation of the components and improved physicalchemical properties (flexibility, tensile and impact strengths, chemical resistance etc.)…”

Phase-Separated Interpenetrating Polymer Networks

“…Thermoplastic AIPNs based on the same CPU and (styrene-acrylic acid) ion-containing (K + ) block copolymer (S-b-AA (K)) prepared by mechanical blending of components in a common solvent were investigated using DMTA and DSC techniques by Bartolotta et al [223]. The local and cooperative molecular mobility of individual CPU, S-b-AA (K), and thermoplastic AIPN of composition CPU/S-b-AA (K) = 80 : 20 (mass %) has been investigated.…”