Copolymerization of carbon dioxide and propylene oxide with zinc glutarate as catalyst in the presence of compounds containing active hydrogen

To enhance the catalytic copolymerization of CO₂ and propylene oxide catalyzed by zinc glutarate, the influence of trace of water, ethanol, and propanal on the catalytic activity, the resulted copolymer structure, and the molecular weight and molecular weight distribution of the copolymer were investigated extensively. The experimental results showed that the catalytic activity decreased remarkably in the presence of either trace of ethanol or water, but increased in the presence of trace of propanal. Both ¹H‐NMR and ¹³C‐NMR spectra suggested that the content of carbonate linkages of resulted copolymer was not effected obviously in the presence of above‐mentioned impurities, giving completely alternating poly(propylene carbonate) (PPC). GPC results indicated that these impurities reduced the molecular weights but broadened the molecular weight distributions of resulted copolymers. Finally, the byproduct contents including both propylene carbonate determined by GC and polyether increased with the increase of three impurity concentrations. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Compatibilization of the poly(lactic acid)/poly(propylene carbonate) blends through in situ formation of poly(lactic acid)‐b‐poly(propylene carbonate) copolymer

The in situ formation of poly(lactic acid)‐b‐poly(propylene carbonate) (PLA‐b‐PPC) block copolymers were carried out by the reaction between PLA and PPC in the presence of tetrabutyl titanate via transesterification. Molecular weight measurements and ¹³C nuclear magnetic resonance spectroscopy revealed that PLA‐b‐PPC block copolymers with higher molecular weight were obtained by controlling the reactivity point ratio between PLA chains and PPC chains in PLA/PPC reaction system. The sample with a composition of PLA:PPC = 40:60 (wt %) and a catalyst amount of 0.5 wt % had a more proportionable reactivity point ratio between PLA chains and PPC chains compared with other samples, resulting in a most conspicuous transesterification and inconspicuous chain scission reaction. Therefore, its high molecular weight fraction (M_w > 40.0 × 10⁴) increased 80%. The formation of macromolecular PLA‐b‐PPC copolymer could strengthen the entanglement between PLA and PPC molecular chains, which resulted in an increased viscosity of blends at low shear rate. In addition, the elongation at break of sample with a composition of PLA:PPC = 40:60 (wt %) and a catalyst amount of 0.5 wt % was nearly as twice as which without catalyst because of the improving miscibility of PLA domains and PPC matrix by the compatibilization of PLA‐b‐PPC copolymer. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46009.     

Mechanical properties of block poly(propylene carbonate‐cyclohexyl carbonate) investigated by nanoindentation and DMA methodologies

To extend the practical application of poly(propylene carbonate) (PPC), the chemical methods were used to improve its mechanical properties. In this connection, random copolymer poly(propylene‐cyclohexyl carbonate) (PPCHC) and di‐block copolymers poly(propylene carbonate‐cyclohexyl carbonate) (PPC‐PCHC) were synthesized. Dynamic mechanical analysis (DMA), nanoindentation and nanoscratch test were applied to evaluate their mechanical properties. The storage's modulus, Young's modulus (E) and hardness (H) obtained from DMA and nanoindentation tests showed that the introduction of the third monomer cyclohexene oxide (CHO) can greatly improve the mechanical properties of PPC, and that the block copolymer PPC‐PCHC hand better mechanical properties than the random copolymer PPCHC. The annealing treated PPC‐PCHCs exhibited deteriorated mechanical properties as compared with untreated PPC‐PCHC. From the results of scratch tests, the plastic deformation of PPC‐PCHC was smaller than those of PPC and PPCHC. Meanwhile, the plastic deformations of the heat‐treated PPC‐PCHCs were smaller than the untreated PPC‐PCHC because of the possible rearrangement of the molecular chains of PPC‐PCHC. The scratch hardness (H_s) of the block copolymer PPC‐PCHC is larger than random polymer PPCHC and PPC, but lower than the values of heat‐treated samples indicating that the surfaces' hardness of block polymers increase after heat treatment. These different measurement methodologies provide a more precise assessment and understanding for the synthesized block polymers. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Catalytic synthesis and characterization of an alternating copolymer from carbon dioxide and propylene oxide using zinc pimelate

New zinc pimelate catalysts used for copolymerization of carbon dioxide and propylene oxide have been synthesized in high yield by a magnetic stirring method. The regular molecular structure of the zinc pimelate was confirmed by Fourier‐transform infrared spectroscopy and wide‐angle X‐ray diffraction techniques. Accordingly, poly(propylene carbonate) (PPC) can be synthesized from carbon dioxide and propylene oxide using these zinc pimelate catalysts. High catalytic efficiency (95.2 gram polymer per gram catalyst or 21 300 g of polymer per mole of zinc) was achieved by optimizing the PO/catalyst ratio. NMR measurement revealed that the PPC synthesized had an alternating copolymer structure. The thermal properties of PPC were determined by modulated differential scanning calorimetry and thermogravimetric analysis. The results demonstrated that the PPC copolymer exhibited an extremely high glass transition temperature of 44.27 °C and decomposition temperature of 257 °C, comparable with values reported in literature. Copyright © 2003 Society of Chemical Industry     

One‐pot regioselective and stereoselective terpolymerization of rac‐lactide,CO2 and rac‐propylene oxide with TPPMCl (M = Cr,Co, Al)/PPNCl binary catalyst

Tetraphenyl porphyrin metal compound (TPPMCl) (where the TPPMCl was TPPCrCl, TPPCoCl, TPPAlCl), in combination with cocatalyst PPNCl (bis(triphenylphosphine)iminium chloride, the molar ratio of TPPMCl to PPNCl was 1:0.5), was used to catalyze the polymerization of racemic lactide (rac‐LA) in racemic propylene oxide (rac‐PO) medium and the terpolymerization of rac‐LA, CO₂ and rac‐PO. It was found that these TPPMCl/PPNCl binary catalysts could initiate the stereoselective polymerization of rac‐LA in rac‐PO medium to form enriched isotactic polylactide (PLA) (P_i ≥ 68.0%) and terpolymerization of CO₂, rac‐LA, rac‐PO to form PPC‐PLA‐PPO (PPC, poly(propylene carbonate); PPO, poly(propylene oxide)) multiblock copolymer. In particular the PPC‐PLA‐PPO multiblock copolymer thus formed displayed high regioregularity and stereoregularity, and has high head‐to‐tail structure content in the PPC block (H‐T% ≥ 63.6%) and high isotacticity in the PLA block (P_i ≥ 64.0%). The influence of catalyst formula, the monomer feeding ratio, reaction temperature, carbon dioxide pressure and reaction time on the terpolymerization was investigated by ¹H NMR, ¹³C NMR, gel permeation chromatography, DSC and TGA. © 2018 Society of Chemical Industry     

Thermally stable poly(propylene carbonate) synthesized by copolymerizing with bulky naphthalene containing monomer

To enhance the thermal and mechanical properties of poly(propylene carbonate) (PPC), the terpolymers were synthesized from carbon dioxide, propylene oxide, and a third monomer, [(2‐naphthyloxy)methyl]oxirane (NMO) using supported zinc glutarate as catalyst. The structure of these terpolymers was confirmed by ¹H NMR spectroscopy. The catalytic activity, molecular weight, carbonate unit content, as well as thermal and mechanical properties were investigated extensively. The experimental results showed that the catalytic activity, molecular weight, and carbonate unit content decreased with the incorporation of NMO. DSC measurements indicated that the introduction of NMO increased the glass transition temperature from 38 to 42°C. TGA tests revealed that the thermal decomposition temperature (T_g?5%) of the synthesized terpolymer increased significantly, being 34°C higher than that of pure PPC. Accordingly, the mechanical properties proved also to be enhanced greatly as evidenced by tensile tests. These thermal and mechanical improvements are of importance for the practical process and application of PPC. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Melt processable and biodegradable aliphatic polycarbonate derived from carbon dioxide and propylene oxide

Alternating poly(propylene carbonate)s (PPC)s were successfully synthesized from carbon dioxide and propylene oxide in higher yield than previously reported. Such thermally stable and high molecular weight copolymers were achieved by optimizing the reaction conditions. The molecular structural change and mechanical properties of the alternating copolymer subjected to melt extrusion were examined by means of modulated differential scanning calorimetry (MDSC), thermogravimetric analysis (TGA), NMR, and tensile tests. The MDSC and TGA results showed that the alternating copolymer generally exhibits a high glass‐transition temperature of above 40°C and a decomposition temperature of above 250°C. These PPCs can be readily melt processed under conditions similar to those for commercial polyolefins. For instance, they can be melt extruded in a temperature range from 150 to 170°C under varying extrusion pressures. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3301–3308, 2003     

Essential work of fracture (EWF) analysis for compression molded alternating poly(propylene carbonate)

In this investigation, the main objective was to study the mechanical properties of alternating poly(propylene carbonate) copolymer (PPC). The PPC used in this study was derived from propylene oxide and carbon dioxide using zinc glutarate as catalyst. The molecular weight of the PPC copolymer used in this study has M?_n～33,000. The synthesized PPC was compression molded into sheets of thickness ～1mm. The fracture toughness of the PPC films was determined using the essential work of fracture (EWF) technique, at a laboratory temperature of 20°C, and a loading rate of 1 mm/min. During the EWF measurement, a significant amount of plastic deformation has taken place around the initial ligament region. The measured specific total fracture work (w_f) was observed to vary in a linear fashion with the specimen ligament (l), and hence satisfied the basic requirement for EWF analysis. The specific essential fracture work (w_e) for the PPC film was measured to be 11.0 kJ/m². The PPC showed a prominent recovery behavior. The severely deformed region surrounding the fracture ligament was observed to recover completely 8 days after fracture testing. Polym. Eng. Sci. 44:580–587, 2004. © 2004 Society of Plastics Engineers.     

Synthesis and characterization of alternating copolymer from carbon dioxide and propylene oxide

High yield and pure zinc glutarate catalysts used for copolymerization of carbon dioxide and propylene oxide have been synthesized in different solvents by ultrasonic methodology. For the purposes of comparison, low‐yield zinc glutarates were also synthesized via mechanical stirring method with other synthetic conditions remaining unchanged. Fourier Transform Infrared Spectroscopy and wide‐angle X‐ray diffraction techniques confirmed the presence of high‐quality zinc glutarate catalysts. Accordingly, poly(propylene carbonate) (PPC) can be synthesized from carbon dioxide and propylene oxide using the zinc glutarate catalysts. It was confirmed that the as‐prepared PPC had an alternating copolymer structure together with high molecular weight. The thermal and mechanical properties of the obtained PPC copolymer were determined by means of differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and tensile test. DSC and TGA results showed that the PPC copolymer exhibited high glass transition temperature (39.39°C) and decomposition temperature (278°C) when compared to their corresponding values reported in the literature. Tensile test showed that the PPC film exhibited superior mechanical strength. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2327–2334, 2002     

Facile synthesis of ethylene–propylene fully alternating copolymer and comparison with random copolymer of similar composition

A precisely sequenced ethylene–propylene (EP) fully alternating copolymer was synthesized via trans‐1,4‐polymerization of isoprene catalyzed by Ziegler–Natta catalyst followed by hydrogenation. This EP copolymer was used as model polymer for studying structure–property relationship. An ethylene–propylene random copolymer (ethylene–propylene rubber [EPR]) with similar ethylene content was also prepared for comparison, and the effect of comonomer sequence distribution on properties was investigated. The copolymer chain structures were monitored by ¹H and ¹³C NMR and Fourier translation infrared. Differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical analysis, and tensile tests were employed to determine the thermal and mechanical properties. The fully alternating copolymer EP gives a more precise glass transition comparing than EPR. Further understanding on thermal properties and aggregation behavior of ethylene–propylene copolymers is made possible by this comparative study. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45816.     

Carbon dioxide/propylene oxide coupling reaction catalyzed by chromium salen complexes

A series of chromium/Schiff base complexes N,N′-bis(salicylidene)-1,2-phenylenediamino chromium^III X were prepared and employed for the alternating copolymerization of carbon dioxide with racemic propylene oxide in the presence of (4-dimethylamino)pyridine. The effect of the complex structure and reaction conditions on the catalytic activity, the poly(propylene carbonate)/cyclic carbonate (PPC/PC) selectivity, and the polymer head-to-tail linkages was examined. The experiments indicated that N,N′-bis(3,5-di-tert-butylsalicylidene)-1,2-phenylenediamino chromium^III (NO₃) exhibited the highest PPC/PC selectivity as well as polymer head-to-tail linkages and N,N′-bis(3,5-dichlorosalicylidene)-1,2-phenylenediimino chromium^III (NO₃) possessed the highest catalytic activity among these chromium/Schiff base complexes. The structure of the produced copolymer was characterized by the IR, ¹H NMR, and ¹³C NMR measurements. Almost 100% carbonate content of the resulting polycarbonate were obtained with the help of these effective catalyst systems under facile conditions.     

Copolymerization of carbon dioxide and propylene oxide using zinc adipate as catalyst

Zinc adipate was synthesized from zinc oxide with adipic acid by different methods. Their chemical structure and crystalline morphology were determined by Fourier transform infrared spectroscopy (FTIR), wide‐angle X‐ray diffraction (WXRD), and scanning electron microscopy (SEM) techniques. The results showed that the zinc adipate synthesized under magnetic stirring possessed higher degree of crystallinity than that synthesized under mechanical stirring due to the different stirring strength, and therefore exhibited greater catalytic activity for the copolymerization between CO₂ and propylene oxide (PO). The optimum condition for the copolymerization of CO₂ and PO was also investigated. Very high catalytic activity of 110.4 g polymer/g catalyst was afforded under optimizing copolymerization condition. NMR spectra revealed that the synthesized poly(propylene carbonate) (PPC) had a highly alternating copolymer structure. DSC and TGA examinations showed that the glass transition temperature and decomposition temperature of the PPC with M_n = 41,900 Da were 27.7 and 248°C, respectively. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 200–206, 2006     

Modification of LLDPE using esterified styrene maleic anhydride copolymer: Study of its properties and environmental degradability

Linear low‐density polyethylene (LLDPE) was blended with decanol‐esterified styrene maleic anhydride copolymer (MDESMA) with an aim to enhance the environmental degradability of polyethylenes. Styrene‐maleic anhydride copolymer (SMA) was synthesized by precipitation polymerization, using benzoyl peroxide (BPO) as initiator. SMA was esterified with a long‐chain monoalcohol, n‐decanol, using methyl ethyl ketone (MEK) as solvent at 80°C to obtain monoesterified styrene‐maleic anhydride (MDESMA). Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimeter (DSC), and thermogravimetric analysis (TGA) were performed to characterize SMA and MDESMA. IR spectra of MDESMA showed a decrease in intensity of peak responsible for carbonyl absorption of a five‐membered ring anhydride group along with broadening of carboxyl O? H stretching peak. TGA showed two‐stage degradation for SMA and MDESMA. LLDPE was blended with MDESMA in single‐screw extruder and blends were characterized thermally by DSC and TGA. A single endothermic melting peak of LLDPE/MDESMA blend was observed. Films of the blends, formed by compression molding, showed an increase in modulus of elasticity but a decrease in elongation at break with increasing concentration of MDESMA. LLDPE/MDESMA blend compositions when kept in phosphate/citric acid buffer solution (pH ～ 8) showed initial weight gain because of water absorption and subsequently loss in weight due to dissolution of soluble component of blends. Film samples of blends kept for soil burial also showed similar behavior. Contact‐angle measurement of film samples of the blends showed an increase in value on soil burial, indicating degradation/dissolution of MDESMA. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 102–108, 2004     

Improved mechanical properties,barrier properties and degradation behavior of poly(butylenes adipate-co-terephthalate)/poly(propylene carbonate) films

Poly(butylene adipate-co-terephthalate) (PBAT) was blended with poly(propylene carbonate) (PPC) by a twin screw extruder and then the blends were made onto films via the blown film technique. PPC dispersed uniformly in the PBAT matrix, and the glass transition temperature (T _g ) of PBAT were decreased with the increasing content of PPC. Wide angle X-ray diffraction confirmed that the crystallite dimension of PBAT was decreased after blending PBAT with the amorphous PPC. The results of mechanical tests indicated that the PBAT/PPC films showed high tensile strength and tear strength. In addition, the PBAT/PPC films showed high carbon dioxide permeability and moderate oxygen and nitrogen permeability. After embedding in soil, the weight loss and mechanical properties analysis demonstrated that the films were remarkably biodegraded. These findings contributed to application of the biodegradable materials, such as design and manufacture polymer packaging.     

Poly(propylene carbonate) polyurethane self‐polishing coating for marine antifouling application

In this contribution, a series of environmentally friendly thermoplastic poly(propylene carbonate) polyurethane (PPCU) were prepared by two‐step condensation polymerization and used to fabricate antifouling coatings. The poly(propylene carbonate) (PPC) segments served as degradable moieties. Quartz crystal microbalance with dissipation (QCM‐D) measurements revealed that the polyurethane could degrade in the presence of enzyme and the degradation rate increases with the decrease of the molecular weight of the polyurethane. Investigation on the hydrolytic degradation behavior and the release rate test of the antifoulants in artificial seawater also demonstrated that the hydrolysis rate and the release rate increased as the molecular weight decreased, which makes the coating controllable at the hydrolysis rate range of 0.012–0.051 g/(m²d). Marine field tests and algae settlement assay tests revealed that the polyurethane coating possessed antibiofouling ability due to its self‐renewal property and the release of antifoulants. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43667.     

Preparation of poly(propylene carbonate)/nano calcium carbonate composites and their supercritical carbon dioxide foaming behavior

Biodegradable polymer foams are attracting extensive attention in both academic and industrial fields. In this study, an emerging biodegradable polymer, poly(propylene carbonate) (PPC), was compounded with nano calcium carbonate (nano‐CaCO₃) and foamed via supercritical carbon dioxide for the first time. Four concentrations of nano‐CaCO₃, 1, 3, 5, and 10 wt %, were used and the thermal properties of PPC/nano‐CaCO₃ composites were investigated. The glass‐transition temperature and thermal decomposition temperature of the PPC/nano‐CaCO₃ composites increased with the addition of nano‐CaCO₃. The morphologies of the PPC/nano‐CaCO₃ composites and the rheological results showed that homogeneous dispersions of nano‐CaCO₃ and percolated nano‐CaCO₃ networks were achieved at a nano‐CaCO₃ content of 3 wt %. Therefore, the finest cell diameter (3.13 μm) and highest cell density (6.02 × 10⁹ cells/cm³) were obtained at the same nano‐CaCO₃ content. The cell structure dependences of PPC and PPC with a nano‐CaCO₃ content of 3 wt % (PPC‐3) foams on the foaming pressure and temperature were investigated as well. The results suggested that the cell structure of PPC‐3 was more stable at different foaming conditions due to the networks of nano‐CaCO₃. Moreover, the change in pressure was more influential on the cell structure than the temperature. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42248.     

Preparation and properties of biodegradable poly(propylene carbonate)/starch composites

Biodegradable composites of poly(propylene carbonate) (PPC) reinforced with unmodified cornstarch were compounded in a batch mixer followed by compression molding. The effects of reinforcement on the morphology, static and dynamic mechanical properties, as well as thermal properties of PPC/starch composites, were investigated. Tensile tests showed that incorporation of starch improves the stiffness and tensile strength of composites significantly. Scanning electron microscopic examination revealed the existence of good interfacial adhesion between the fillers and PPC matrix. Moreover, experimental results indicated that the starch addition leads to a significant improvement in the thermal stability of the composites. This paper demonstrates that the incorporation of low‐cost and biodegradable cornstarch into PPC provided a practical way to produce completely biodegradable and cost‐competitive composites with good mechanical properties. Polym. Eng. Sci. 44:2134–2140, 2004. © 2004 Society of Plastics Engineers.     

Preparation,thermal properties,and morphology of graft copolymers in reactive blends of PHBV and PPC

Chemical modification of poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV) with glycidyl methacrylate (GMA) monomer, followed by reactively blending with end‐capped poly(propylene carbonate) (PPC) (50 wt%) was carried out during melt processing with dicumyl peroxide (DCP) initiation. The two kinds of graft copolymers of PHBV‐g‐GMA and PHBV‐g‐PPC were extracted with Soxhlet's apparatus, respectively. These grafting reaction mechanisms were proposed and the presence of grafting copolymers was confirmed by weight analysis, FTIR and NMR. The methyne carbon of GMA is confirmed to attach to quaternary carbon of the PHBV backbone. The epoxy groups in the copolymer of PHBV‐g‐GMA were capable to react with the carboxyl groups of end‐capped PPC, resulting in the formation of PHBV‐g‐PPC copolymer in situ. Their thermal properties and morphology were also characterized by DSC, WAXD, POM, and AFM. It revealed that after GMA grafting, the degradation of PHBV decreased and the nucleation of PHBV improved. The crystallinity degree, spherulites dimension and phase segregation between the two macromolecules decreased after PHBV grafted with PPC. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers     

Membranes of triphenylsilyl substituted polyphenylene oxide in the permeation of propylene and propane gases

Poly(2,6‐dimethyl‐1,4‐phenylene oxide) (PPO) was chemically modified by the attachment of a bulky triphenylsilyl (TPS) group substituent (～30 mol %) to study its impact on hydrocarbon gas permeation. A membrane of the modified PPO (TPS–PPO) was tested for the permeation of pure propylene and propane gas and that of their 55:45 binary mixture at 30 ± 2°C. Gravimetric single‐gas equilibrium sorption studies were carried out to determine the gas solubility coefficients and diffusion coefficients to assess their role in the gas permeation mechanism of the membranes. Characterization studies were done to determine the interrelationship between the transport properties and the polymer structure. The studies included density, fractional free volume, Fourier transform infrared spectroscopy, ¹H‐NMR, differential scanning calorimetry, wide‐angle X‐ray diffraction, tensile testing, and scanning electron microscopy. The TPS–PPO membrane was found to be 3 times more permeable to propylene and 3.8 times more permeable to propane with a small decrease in the propylene/propane ideal permselectivity (3.37) when compared to that of unmodified PPO (4.25). TPS–PPO could be a potential membrane material for the efficient recovery of propylene and propane from mixtures with permanent gases such as those found in refinery off‐gas. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

The functions of crystallizable ethylene‐propylene copolymers in the formation of multiple phase morphology of high impact polypropylene

The functions of crystallizable ethylene‐propylene copolymers in the formation of multiple phase morphology of high impact polypropylene (hiPP) were studied by solvent extraction fractionation, transmission electron microscopy (TEM), selected area electron diffraction (SAED), nuclear magnetic resonance (¹³C‐NMR), and selected reblending of different fractions of hiPP. The results indicate that hiPP contains, in addition to polypropylene (PP) and amorphous ethylene‐propylene random copolymer (EPR) as well as a small amount of polyethylene (PE), a series of crystallizable ethylene‐propylene copolymers. The crystallizable ethylene‐propylene copolymers can be further divided into ethylene‐propylene segmented copolymer (PE‐s‐PP) with a short sequence length of PE and PP segments, and ethylene‐propylene block copolymer (PE‐b‐PP) with a long sequence length of PE and PP blocks. PE‐s‐PP and PE‐b‐PP participate differently in the formation of multilayered core‐shell structure of the dispersed phase in hiPP. PE‐s‐PP (like PE) constructs inner core, PE‐b‐PP forms outer shell, while intermediate layer is resulted from EPR. The main reason of the different functions of the crystallizable ethylene‐propylene copolymers is due to their different compatibility with the PP matrix. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012