Synthesis,characterization and properties of organoclay‐modified polyurethane/epoxy interpenetrating polymer network nanocomposites

organoclay‐modified polyurethane/epoxy interpenetrating network nanocomposites (oM‐PU/EP nanocomposites) were prepared by adding organophilic montmorillonite (oMMT) to interpenetrating polymer networks (IPNs) of polyurethane and epoxy resin (PU/EP) which had been prepared by a sequential polymerization technique. Wide‐angle X‐ray diffraction (WAXD) and transmission electronic microscopy (TEM) analysis showed that the interpenetrating process of PU and EP improved the exfoliation and dispersion degree of oMMT. The effects of the NCO/OH ratio (isocyanate index), the weight ratio of PU/EP and oMMT content on the phase structure and the mechanical properties of the oM‐PU/EP nanocomposites were studied by tensile testing and scanning electronic microscopy (SEM). Water absorption tests showed that the PU/EP interpenetrating networks and oMMT had synergistic effects on improvement in the water resistance of the oM‐PU/EP nanocomposites. Differential scanning calorimetry (DSC) analysis showed that PU was compatible with EP and that the glass transition temperature (T_g) of the oM‐PU/EP nanocomposites increased with the oMMT content up to 3 wt%, and then decreased with further increasing oMMT content. The thermal stability of these nanocomposites with various oMMT contents was studied by thermogravimetric analysis (TGA), and the mechanism of thermal stability improvement was discussed according to the experimental results. Copyright © 2005 Society of Chemical Industry     

The effect of composition and the level of crosslinking of the poly(methylmethacrylate) phase on the properties of natural rubber‐poly(methylmethacrylate) semi‐2 interpenetrating polymer networks

The effects of the PMMA content and the cross‐linker level in the poly(methylmethacrylate) component on the dynamic and physico‐mechanical properties of semi‐2 interpenetrating polymer networks based on natural rubber and poly(methylmethacrylate) were determined. The miscibility of the components in these semi‐2 interpenetrating polymer networks was determined using the loss tangent data, obtained from dynamic mechanical thermal analysis and the interphase contents were calculated from modulated scanning calorimetric data. Some component mixing in these semi‐2 interpenetrating polymer networks was evident from these modulated differential scanning calorimetric and dynamic mechanical thermal analysis data. The degree of component mixing increased with cross‐linker level in the PMMA phase. The PMMA content in the semi‐2 IPNs has a significant effect on the tensile and hysteresis behavior of these semi‐2 interpenetrating polymer networks. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Structure–properties investigations in hydrophilic nanocomposites based on polyurethane/poly(2–hydroxyethyl methacrylate) semi‐interpenetrating polymer networks and nanofiller densil for biomedical application

Nanocomposites based on sequential semi–interpenetrating polymer networks (semi–IPNs) of crosslinked polyurethane and linear poly(2‐hydroxyethyl methacrylate) filled with 1–15 wt % of nanofiller densil were prepared and investigated. Nanofiller densil used in an attempt to control the microphase separation of the polymer matrix by polymer–filler interactions. The morphology (SAXS, AFM), mechanical properties (stress–strain), thermal transitions (DSC) and polymer dynamics (DRS, TSDC) of the nanocomposites were investigated. Special attention has been paid to the raising of the hydration properties and the dynamics of water molecules in the nanocomposites in the perspective of biomedical applications. Nanoparticles were found to aggregate partially for higher than 3 and 5 wt % filler loading in semi–IPNs with 17 and 37 wt % PHEMA, respectively. The results show that the good hydration properties of the semi–IPN matrix are preserved in the nanocomposites, which in combination with results of thermal and dielectric techniques revealed also the existence of polymer–polymer and polymer–filler interactions. These interactions results also in the improvement of physical and mechanical properties of the nanocomposites in compare with the neat matrix. The improvement of mechanical properties in combination with hydrophilicity and biocompatibility of nanocomposites are promising for use these materials for biomedical application namely as surgical films for wound treatment and as material for producing the medical devises. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43122.     

Structuring and characterization of a novel microporous PVDF membrane with semi‐interpenetrating polymer networks for vacuum membrane distillation

In this paper, by using the non‐solvent induced phase separation (NIPS) process, a new microporous membrane with semi‐interpenetrating polymer network (semi‐IPN) was produced in which PDMS polymer is crosslinked and PVDF polymer is linear. For the fabrication of the membrane, tetraethylorthosilicate (TEOS) was used as the crosslinking agent and dibutyltin dilaurate (DBTDL) was used as the catalyst. By changing the mass ratio of PDMS/TEOS, the structure and the performance of the prepared membrane were studied. The membranes were also investigated by scanning electron microscopy (SEM‐EDX), X‐ray diffraction (XRD), attenuated total reflection Fourier transform infrared (ATR‐FTIR) spectroscopy, capillary flow porometer, thermogravimetric analysis (TGA), water contact angle (WCA), etc. Through the experiments we found that the semi‐IPNs structure was more likely produce the sponge‐like pores and was more favorable to the mechanical properties, pore structure and thermal stability of the membranes. Using the PDMS–PVDF membranes for the VMD desalt of the NaCl solution (30 g/L), 99.9% salt rejection and reasonable fluxes were obtained, which make us believe that it could be possible to use the semi‐IPNs PDMS–PVDF membrane to treat real sea water for its desalt. POLYM. ENG. SCI., 57:1311–1321, 2017. © 2017 Society of Plastics Engineers     

Semi‐interpenetrating polymer networks based on polyurethane and poly(vinyl pyrrolidone) obtained by photopolymerization: Structure‐property relationships and bacterial adhesion

A range of semi‐interpenetrating polymer networks (semi‐IPNs) based on polyurethane (PU) and poly(vinyl pyrrolidone) (PVP) have been synthesized and characterized with respect to their thermodynamic characteristics, morphology, mechanical properties, surface properties, water sorption and bacterial adhesion. The free energies of mixing of PU and PVP in semi‐IPNs have been determined by the vapor sorption method and were shown to be positive for all compositions. The surface properties of semi‐IPNs were investigated using the dynamic contact angle analysis. It was shown that the advancing contact angle changes from 83.1° to 65.3° with increasing PVP from 7.05% to 57.38%. Scanning electron microscopy demonstrated that the semi‐IPNs are two‐phase systems with incomplete phase separation. The mechanical properties reflect the changes in structure of semi‐IPNs with increasing of amounts of PVP in the system. Incorporation of PVP into the semi‐IPN with PU restricts the ability of PVP to sorb water. As infection is likely to be caused by bacterial adherence to biomedical implants, the bacterial adhesion data suggests that the semi‐IPNs with PVP content below 22.52% may be useful for biomedical material applications. Polym. Eng. Sci. 44:940–947, 2004. © 2004 Society of Plastics Engineers.     

Radiation synthesis and environmental responsiveness of semi‐interpenetrating polymer networks composed of poly(dimethyl–aminoethyl methacrylate) and poly(ethylene oxide)

Semi‐interpenetrating polymer networks (semi‐IPNs) composed of poly(dimethyl–aminoethyl methacrylate) (PDMAEMA) and poly(ethylene oxide) (PEO) were synthesized by γ‐radiation; three semi‐IPNs with 80 : 20, 90 : 10, and 95 : 5 weight ratios of DMAEMA/PEO were obtained by use of this technique. The gel–dose curves showed that the hydrogels were characterized by a structure typical of semi‐IPNs and the results of elemental analysis supported this point. The temperature‐induced phase transition of semi‐IPNs with the composition of 95 : 5 was still retained, with the lower critical solution temperature of PDMAEMA shifting from 40 to 27°C. The temperature sensitivity of the other two semi‐IPNs gradually disappeared. The pH sensitivity of three semi‐IPNs was still retained but the pH shifted slightly to lower values with increasing PEO content in the semi‐IPNs. The effect of PEO content in semi‐IPNs on their environmental responsiveness was discussed. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2995–3001, 2004     

Thermal,optical, and water sorption properties in composite films of poly(ether imide) and bismaleimides: Effect of chemical structure

Two series of semi‐interpenetrating polymer network (semi‐IPN) composite films, PEI/bismaleimide (UTBM) and PEI/fluorinated BMI (UTFBM) were prepared using a thermoplastic PEI and two different crosslinkable imide moieties. The effects of chemical structure and content of crosslinkable imide moieties on thermal stability, dielectric properties, and water sorption have been investigated. Glass transition temperature and weight loss temperatures increased with increase in the content of crosslinkable imide moieties, indicating the enhanced thermal stability of the semi‐IPN composite films. The refractive indices of the semi‐IPN composite systems increased with increasing crosslinkable imide moieties due to the higher polarizabilities of atoms. The water sorption of the semi‐IPN composite films was significantly decreased by the incorporation of crosslinkable imide moieties, which are interpreted by morphological structure. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Tuning the Mechanical Properties of BIEE‐Crosslinked Semi‐Interpenetrating,Double‐Hydrophilic Hydrogels

Double‐hydrophilic, semi‐interpenetrating (semi‐IPN) hydrogels are synthesized by encapsulating hydrophilic polyvinylpyrrolidone (PVP) linear chains in structure‐defined 1,2‐bis‐(2‐iodoethoxy)ethane (BIEE)‐crosslinked (poly(2‐(dimethylamino)ethyl methacrylate) (pDMAEMA) hydrogels. A series of semi‐IPN double‐hydrophilic hydrogels are prepared in which the pDMAEMA/BIEE content is kept the same and only the PVP content is varied, from 0 up to 33 wt%. The mechanical properties of the water‐swollen hydrogels are experimentally evaluated under unconfined compressive loading conditions, while a nonlinear hyperelastic constitutive equation is used to predict their mechanical response. No significant difference is found in the mechanical response of the semi‐IPN PVP/pDMAEMA/BIEE hydrogel containing 5 wt% PVP compared to the pDMAEMA/BIEE analog, however, for greater loading percentages (15 and 33 wt% of PVP), the semi‐IPN hydrogels exhibit less stiffness/higher ductility. Furthermore, in vitro biocompatibility studies are carried out for the pDMAEMA/BIEE and the semi‐IPN PVP/pDMAEMA/BIEE, indicating that both the formulations exhibit no toxicity in cultured cells.     

Dynamic mechanical modeling of PEI/dicyanate semi‐IPNs

The dynamic mechanical behavior of polyetherimide(PEI)/dicyanate semi‐interpenetrating polymer networks (semi‐IPNs) was analyzed by using the conventional Takayanagi model for the sea‐island morphology (PEI content of 10% or below) and a polyhedron model, which we developed for the dicyanate nodular structure (PEI content of 20% or above). The model parameters for the Takayanagi model were determined by the volume fraction of the PEI dispersed phase and Kerner's equation, while the model parameters for the polyhedron model were simply calculated by introducing a phase continuity factor. Both models correlate well with the morphology revealed in the micrographs except near the transition temperature of the PEI‐rich phase. The additional shift toward higher temperature found in the nodular structure was due to the intermixed phase composition, and the effect was quantified by measuring the calorimetric transition temperature. The dynamic mechanical modeling for the dual‐phase morphology (PEI content of 15%) and for the semi‐IPNs showing a morphology spectrum were also successfully accomplished by combining the Takayanagi model and the polyhedron model.     

Salt and pH sensitive semi‐interpenetrating polyelectrolyte hydrogels poly(HEMA‐co‐METAC)/PEG and its BSA adsorption behavior

A novel semi‐interpenetrating poly(2‐hydroxyethyl methacrylate) (pHEMA) based polyelectrolyte hydrogel [p(HEMA‐co‐METAC)/PEG] was prepared by copolymerizing HEMA with the cationic monomer 2‐methacryloyloxyethyltrimethyl ammonium chloride (METAC) in the presence of polyethylene glycol (PEG) with different content and molecular weight (MW 4000 and 400). The chemical structure of the gels was confirmed by FT‐IR spectroscopy, morphology study was performed by scanning electron microscope (SEM), thermal stability was revealed by thermogravimetric analysis (TGA), and the mechanical properties were determined by electronic universal testing machine. Swelling studies showed introduction of cationic monomer METAC led to high water content, and the obvious salt and pH sensitive properties were observed which proved the smart behavior of the semi‐interpenetrating polymer networks (IPNs) gels. In addition, the effect of temperature and some important biological solution on swelling behavior were reported. Cytotoxicity test demonstrated that synthesized gels owned satisfactory cytocompatibility and were convenient for the application as biomaterials. Finally, the weak bovine serum albumin (BSA) adsorption on semi‐IPNs by introducing METAC and controlling the content of PEG in gels demonstrated that they were of good protein resistance effect in biomedical applications. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41537.     

Effects of silica nanoparticles on tribology performance of poly(Epoxy Resin‐Bismaleimide)‐based nanocomposites

Introduction of small nanoparticles into polymer matrix increases the mechanical, tribological, and thermal properties of nanocomposites. In this study, poly(epoxy resin‐bismaleimide‐diaminodiphenylmethane) (EP‐BMI‐DDM) copolymers filled with silica nanoparticles (SNPs) were successfully fabricated through in situ suspension polymerization. To enhance the interfacial adhesion of silica particles to the polymer matrix, the nanoparticles were organo‐modified by silane coupling agent. Results of tensile strength test revealed that increased toughness of the composites was attributed to the microcavitations induced by organo‐modified SNPs (OSNPs). Proper loadings of OSNPs can play a critical role in antifriction performance, with optimal friction coefficient of 0.17 (2 wt% OSNPs content). Thermostabilities of the nanocomposites were characterized by differential thermal gravimetric analysis. At the maximum rate of weight loss of EP‐BMI‐DDM/3 wt% OSNP, the temperature measured 452°C, which is 52°C higher than that of pure EP‐BMI‐DDM copolymers (400°C). The produced nanocomposites feature good thermostability and self‐lubrication can be widely used as wearable material under severe working conditions with higher temperature. POLYM. ENG. SCI., 59:274–283, 2019. © 2018 Society of Plastics Engineers     

Effect of hybrid network formation on adhesion properties of polycyanurate/polyurethane semi‐interpenetrating polymer networks

The adhesion characteristics of modified polycyanurates based on the principle of semi‐interpenetrating polymer networks (semi‐IPNs) have been studied. It has been shown that the formation of a polycyanurate network in the presence of linear polyurethane (LPU) leads to increasing adhesion strength to aluminum and titanium. The peculiarities of polycyanurate network (PCN) formation in the presence of different amounts of LPU are discussed. It has been found that chemical incorporation of LPU into PCN occurs during network formation owing to chemical interaction of urethane groups with cyanate groups of growing PCN. At LPU content in the initial composition up to around 20 wt% only a hybrid network is formed. The maximal values of adhesive strength to aluminum and titanium are achieved at LPU content of 20–25%, corresponding to formation of a hybrid network. The further increase of LPU content leads to the presence of non‐incorporated LPU (semi‐IPN formation) in the adhesive layer and to reduction of the adhesive strength.     

Curing and mechanical properties of dicyanate/poly(ether sulfone) semi‐interpenetrating polymer networks

Semi‐interpenetrating polymer networks (semi‐IPNs) composed of a dicyanate resin and a poly(ether sulfone) (PES) were prepared, and their curing behavior and mechanical properties were investigated. The curing behavior of the dicyanate/PES semi‐IPN systems catalyzed by an organic metal salt was analyzed. Differential scanning calorimetry was used to study the curing behavior of the semi‐IPN systems. The curing rate of the semi‐IPN systems decreased as the PES content increased. An autocatalytic reaction mechanism was used to analyze the curing reaction of the semi‐IPN systems. The glass‐transition temperature of the semi‐IPNs decreased with increasing PES content. The thermal decomposition behavior of the semi‐IPNs was investigated. The morphology of the semi‐IPNs was investigated with scanning electron microscopy. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1079–1084, 2003     

Preparation and properties of porous poly(sodium acrylate‐co‐acrylamide) salt‐resistant superabsorbent composite

A novel semi‐interpenetrating polymer networks (semi‐IPNs) porous salt‐resistant superabsorbent composite was prepared by copolymerization of partially neutralized acrylic acid and acrylamide using polyethylene glycol as semi‐IPNs composite, N,N′‐methylenebisacrylamide, triene propanol phosphate, and trihydroxymethyl propane glycidol ether as crosslinking agents, methanol, propanol, and butanol as foaming agents, and L ‐ascorbic acid and peroxide hydrogen as initiators. To improve the properties of swollen hydrogel, such as strength, resilience, permeabilities, and dispersion, the copolymer was surface‐crosslinked, and then blended with aluminum sulfate, sodium carbonate, and sodium 1‐octadecanol phosphate in the course of post treatment. The influences of reaction conditions on properties of superabsorbent composite were investigated and optimized, and the water absorbency of superabsorbent composite prepared at optimal conditions in 0.9 wt% NaCl aqueous solution under atmospheric pressure and certain load (P ≈ 2 × 10³ Pa) were 61 g g^?1 and 16.7 g g^?1, respectively. Moreover, the swelling rate reached 22.003 × 10^?3 g (g s)^?1. And the excellent hydrogel properties, such as hydrogel strength, resilience, permeabilities, and dispersion were also obtained. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers     

Phase separation in the polyurethane/poly(2‐hydroxyethyl methacrylate) semi‐interpenetrating polymer networks synthesized by different ways

The thermal, dynamic mechanical analysis, morphology and mechanical properties of semi‐interpenetrating polymer networks based on crosslinked polyurethane (PU) and poly(2‐hydroxyethyl methacrylate) (PHEMA) synthesized by photopolymerization and by thermopolymerization have been investigated. The thermal analysis has evidenced the two glass temperature transitions in the semi‐IPNs and this is confirmed by the thermodynamic miscibility investigation of the systems. The Dynamic Mechanical Analysis spectra have shown that the phase separation is more significant in the thermopolymerized semi‐IPNs: the tan δ peaks of constituent polymers are more distinct and the minimum between the two peaks is deeper. The calculated segregation degree values of semi‐IPN's components are significantly higher for thermopolymerized semi‐IPNs, thereby the process of phase separation in the thermopolymerized semi‐IPNs is more developed. The structures of two series of samples investigated by SEM are completely different. The mechanical properties reflect these changes in structure of semi‐IPNs with increasing amount of PHEMA and with the changing of the method of synthesis. The results suggest that the studied semi‐IPNs are two‐phase systems with incomplete phase separation. The semi‐IPN samples with early stage of phase separation demonstrate higher mechanical characteristics. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers     

Novel semi‐interpenetrating network structural phase change composites with high phase change enthalpy

High phase change enthalpy, controllable temperature, and stable shape can expand the application of phase change materials (PCMs) in energy storage. In this study, a series of novel form‐stable PCMs with high phase change enthalpy (169–195 J/g) and controllable temperature (45.3–61.4°C) were prepared. The PCMs exhibited a semi‐interpenetrating polymer network (semi‐IPN) structure resulting from the combination of polyethylene glycol (PEG) and a three‐dimensional (3‐D) network gel. The gel itself featured an inherent phase change characteristic and a 3‐D network structure. Thus, it improved the phase transition enthalpy of the materials and facilitated the formation of a semi‐IPN that endowed the materials with excellent form‐stable properties. In addition, the latent heat of the composites (169–195 J/g) is much higher than most of the previously reported composites using PEG as phase change component (68–132 J/g). © 2017 American Institute of Chemical Engineers AIChE J, 64: 688–696, 2018     

Graphene nanoplatelet‐reinforced semi‐crystal poly(arylene ether nitrile) nanocomposites prepared by the twin‐screw extrusion

Graphene nanoplatelet reinforced semi‐crystal poly(arylene ether nitrile) (PEN/GN) nanocomposites were prepared by an economically and environmentally friendly method of twin‐screw extrusion technique. The feasibility of using PEN/GN nanocomposites was investigated by evaluating their thermal behaviors, mechanical, and morphological properties. Thermal studies revealed that GN could act as nucleating agents but decreased the whole crystallinity in/of PEN/GN nanocomposites. Mechanical investigation manifested that GN had both strengthening effect (increase in flexural modulus and strength) and toughening effect (rise in the elongation and impact strength) on the mechanical performance of semi‐crystal PEN nanocomposites. Heat treatment can further increase their mechanical performances due to the increased crystallinity and release of inner stress. With the small addition of GN (<5 wt%), the morphology of PEN was changed from brittle to ductile, and GN showed good dispersion and adhesion in/to the PEN matrix. This work shows that in the semi‐crystal polymer/filler systems, besides the dispersion states of fillers and interactions between fillers and polymer matrices, the crystallinity of the nanocomposites affected by the existence of filler and the residual stress are also two key factors determining the mechanical properties. POLYM. COMPOS., 35:404–411, 2014. © 2013 Society of Plastics Engineers     

Semi‐interpenetrating polymer networks based on polyurethane and polyvinylpyrrolidone. II. Dielectric relaxation and thermal behaviour

Semi‐interpenetrating polymer networks (semi‐IPNs) based on crosslinked polyurethane (PU) and linear polyvinylpyrrolidone (PVP) were synthezised, and their thermal and dynamic mechanical properties and dielectric relaxation behavior were studied to provide insight into their structure, especially according to their composition. The differential scanning calorimetry results showed the glass transitions of the pure components: one glass‐transition temperature (T_g) for PU and two transitions for PVP. Such glass transitions were also present in the semi‐IPNs, whatever their composition. The viscoelastic properties of the semi‐IPNs reflected their thermal behavior; it was shown that the semi‐IPNs presented three distinct dynamic mechanical relaxations related to these three T_g values. Although the temperature position of the PU maximum tan δ of the α‐relaxation was invariable, on the contrary the situation for the two maxima observed for PVP was more complex. Only the maximum of the highest temperature relaxation was shifted to lower temperatures with decreasing PVP content in the semi‐IPNs. In this study, we investigated the molecular mobility of the IPNs by means of dielectric relaxation spectroscopy; six relaxation processes were observed and indexed according the increase in the temperature range: the secondary β‐relaxations related to PU and PVP chains, an α‐relaxation due to the glass–rubber transition of the PU component, two α‐relaxations associated to the glass–rubber transitions of the PVP material, and an ionic conductivity relaxation due to the space charge polarization of PU. The temperature position of the α‐relaxation of PU was invariable in semi‐IPNs, as observed dynamic mechanical analysis measurements. However, the upper α‐relaxation process of PVP shifted to higher temperatures with increasing PVP content in the semi‐IPNs. We concluded that the investigated semi‐IPNs were two‐phase systems with incomplete phase separation and that the content of PVP in the IPNs governed the structure and corresponding properties of such systems through physical interactions. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1191–1201, 2003     

聚苯乙烯互穿聚合物网络研究进展

综述了聚苯乙烯互穿聚合物网络的研究进展,阐述了分步互穿聚合物网络、同步互穿聚合物网络、半互穿聚合物网络和胶乳互穿聚合物网络的制备方法,介绍了组成和制备方法对PS互穿聚合物网络的相态结构和互穿聚合物网络相容性的影响。阐述了PS互穿聚合物网络的组成和结构对于力学性能、热力学性能、流变性能、气体透过率和吸附性的影响,最后综述PS互穿聚合物网络存在的问题及发展趋势。     

Semi‐ and full‐interpenetrating polymer networks based on polyurethane produced from canola oil and poly(methyl methacrylate)

Semi‐ and full‐interpenetrating polymer networks (IPNs) were prepared using polyurethane (PUR) produced from a canola oil‐based polyol with primary terminal functional groups and poly(methyl methacrylate) (PMMA). The properties of the material were studied and compared using dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), and tensile measurements. The morphology of the IPNs was investigated using atomic force microscopy (AFM). Semi‐IPNs demonstrated different thermal mechanical properties, mechanical properties, phase behavior, and morphology from full IPNs. Both types of IPNs studied are two‐phase systems with incomplete phase separation. However, the extent of phase separation is significantly more advanced in the semi‐IPNs compared with the full IPNs. All the semi‐IPNs exhibited higher values of elongation at break for all proportions of acrylate to polyurethane compared with the corresponding full IPNs. These differences are mainly due to the fact that in the case of semi‐IPNs, one of the constituting polymers remains linear, so that it exhibits a loosely packed network and relatively high mobility, whereas in the case of full IPNs, there is a higher degree of crosslinking, which restricts the mobility of the chains. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009