Preparation and characterization of soy protein plastics plasticized with waterborne polyurethane

Utilizing anionic waterborne polyurethane (WPU) as a plasticizer, for the first time, we prepared new soy protein isolate (SPI) plastics. The WPU was prepared by using the emulsion‐extending‐chain method, and mixed with soy protein in aqueous dispersion. The mixture was cast, cured, pickled and hot‐pressed to form SPI plastics plasticized with WPU. The plastics sheets were characterized by infrared spectroscopy, scanning electron microscopy, ultraviolet spectrophotometry and wide‐angle X‐ray diffraction, and their properties were measured by using dynamic mechanical analysis, differential scanning calorimetry and tensile testing. The results revealed that SPI plastics plasticized with WPU possess good mechanical properties, such as a tensile strength (σ_b) of 7–19 MPa, water resistance (σ_b(wet)/σ_b(dry) = 0.4–0.5), optical transmittance and thermal stability, because of the good miscibility and strong interaction between WPU and SPI. With an increase of WPU content from 20 to 50 wt%, the elongation at break (ε_b) value of the sheets increased from 50 up to 150 %, and is much higher than that of the pure SPI sheet. WPU as a plasticizer can play an important role in improving the properties of SPI plastics. Copyright © 2004 Society of Chemical Industry     

Effects of lignin as a filler on properties of soy protein plastics. II. Alkaline lignin

Blend plastics based on soy protein isolate (SPI) strengthened with alkaline lignin (AL) in the weight ratio of 10:0 to 5:5 were prepared with 40 wt % glycerol as a plasticizer by compression molding. The structure and mechanical properties of the blends were investigated by wide‐angle X‐ray diffraction (WAXD), differential scanning calorimetry (DSC), dynamical mechanical thermal analysis (DMTA), and tensile tests. The results indicated that the introduction of AL could effectively increase the tensile strength and Young's modulus, thermal stability, and elongation of the compositive plastics when the AL content ranged from 10 to 20 parts. Moreover, the blend plastics containing 50 parts AL exhibited maximum tensile strength (1.98 MPa) and much higher than that with the SP–AL0 sheet with AL alone (0.89 MPa). In addition, tests of water absorption proved that the introduction of hydrophobic AL effectively reduced water absorption and, hence, decreased water sensibility. Therefore, AL, a relatively low‐cost filler, plays a major role in enhancing the strength and water resistivity of soy protein plastics. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3291–3297, 2003     

Soy protein–lignosulphonate plastics strengthened with cellulose

A series of biodegradable plastics from soy protein and lignosulphonate (SL) were strengthened with cellulose powder (CP) by melt blending and compression molding. The effects on the morphology and properties of the blends of introducing CP were investigated by wide‐angle X‐ray diffraction, differential scanning calorimetry, dynamic mechanical thermal analysis, scanning electron microscopy, and tests of tensile and water absorption. It is worth noting that introducing CP obviously improved the mechanical properties and water resistivity of composite plastics. With an increase in CP content, the tensile strength and Young's modulus of the blend materials increased. The experimental results indicate that a certain degree of miscibility between SL and CP and a strong interaction among various molecules of the components, resulting in strengthened materials. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1685–1689, 2003     

Effects of lignin as a filler on properties of soy protein plastics. I. Lignosulfonate

A series of biodegradable plastics from soy protein isolate (SPI) and lignosulfonate (LS) with a weight ratio of 0:10 to 6:4 were prepared with 40 wt % glycerol as a plasticizer by compression molding. Their properties were investigated by wide‐angle X‐ray diffraction (WAXD), differential scanning calorimetry (DSC), dynamical mechanical thermal analysis (DMTA), scanning electron microscopy (SEM), and tensile tests. The results indicated that the introduction of a moderate LS content from 30 to 40 parts in the blends could simultaneously enhance the tensile strength, elongation, and Young's modulus of soy protein plastics alone. Studies of the water sensitivity of the materials suggested that the strong interaction between LS and SPI could restrict the effect of water on the swelling and the damage of the materials, resulting in lower water absorption. The improvement of the properties was attributed mainly to the existence of the beneficial microphase separation and the formation of crosslinked structures because of the introduction of LS into soy protein plastics. Therefore, a model of a crosslinked network formed from SPI molecules with an LS center was established based on the existence of strong physical interactions between LS and SPI. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3284–3290, 2003     

Composite sheets with biodegradable polymers and paper,the effect of paper strengthening agents on strength enhancement,and an evaluation of biodegradability

Composite sheets composed of biodegradable polymers (BP) and paper were prepared, and their physical and biodegradable properties were investigated. The paper sheets were soaked in BP emulsions and cured at 100°C for 20 min. The wet strength of composite sheets with the same basis weight increased significantly with increasing BP content, although dry strength increased only moderately. A 0.5% addition of a common wet paper‐strengthening agent, poly(amidoamine‐epichlorohydrin) (PAE) resin, enhanced the wet strength, which reached 9.3 MPa, of composite sheets consisting of a BP : paper ratio of 20 : 80. Further enhancement was achieved by the addition of polyvinylamines (PVAm). The wet tensile strength of composite sheets consisting of BP and paper (20 : 80) increased by 27% with the addition of 0.2% PVAm and 0.5% PAE, whereas it was enhanced by only 3–4% with the addition of 0.7% PAE. The biodegradability of the composite sheets was somewhat retarded by the addition of PAE and PVAm. However, a 90% weight loss was observed 60 days after placing composite sheet samples in soil. A similar weight loss was observed after 45 days for composites without additives and after 30 days for base paper alone. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 861–866, 2005     

Effect of the synthesis route on the structure and properties of polyurethane/nitrokonjac glucomannan semi‐interpenetrating polymer networks

With a synthesis route differing from previous methods, novel semi‐interpenetrating polymer networks (semi‐IPNs), coded UNK‐II, were synthesized by the initial mixing of nitrokonjac glucomannan (NKGM) with castor oil in butanone and the subsequent addition of toluene diisocyanate (TDI) to begin the polymerization reaction in the presence of 1,4‐butanediol (BD) as a chain extender at 60°C. The results from dynamic mechanical analysis, differential scanning calorimetry, and ultraviolet spectroscopy indicated that a certain degree of microphase separation occurred between soft and hard segments of polyurethane (PU) in the UNK‐II sheets. The α‐transition temperature, glass‐transition temperature, heating capacity, and tensile strength increased with an increase in the NKGM content, and this suggested an interaction between PU and NKGM in the UNK‐II sheets. In a previous method, semi‐IPN materials (PUNK) were synthesized by the polymerization reaction between castor oil and TDI, and then this PU prepolymer was mixed with NKGM and cured in the presence of BD as a chain extender. The PUNK sheets had relatively good miscibility and mechanical properties. However, for UNK‐II sheets prepared by the method reported in this work, NKGM mainly played a role in reinforcement. When the NKGM content was less than 10%, the UNK‐II sheets exhibited good miscibility, tensile strength (26–28 MPa), and breaking elongation (130–140%), similar to those of PUNK materials. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1948–1954, 2003     

头发角蛋白塑料的制备和力学性能研究

将头发氧化后得到的角蛋白粉末用模压的方法制备了角蛋白塑料，考察了模压压强、模压温度、头发的氧化时间以及增塑剂水和甘油的含量等对角蛋白塑料力学性能的影响，并对其角蛋白塑料进行了热重分析和红外表征。实验结果表明随着模压压强的增大，塑料的最大拉伸强度升高，断裂伸长率降低。而模压温度对塑料的力学性能影响不大。随着氧化时间的延长，最大拉伸强度升高，断裂伸长率降低。水和甘油都是头发角蛋白塑料良好的增塑剂，水含量为26．8％或甘油含量为20％时的增塑作用最好，此时最大拉伸强度分别可达15．15MPa和25．33MPa，断裂伸长率分别为17．81％和9．65％。     

Properties of crosslinked casein/waterborne polyurethane composites

Waterborne polyurethane (WPU) and casein (1 : 1 by weight) were blended at 90°C for 30 min, and then were crosslinked by adding 1–10 wt % ethanedial to prepare a series of sheets. Their structure and properties were characterized by using infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, dynamic mechanical analysis, and tensile testing. The results indicated that crosslinked blend sheets exhibited a certain degree of miscibility, and exhibited much higher tensile strength and water resistivity than did the WPU, casein, and the uncrosslinked blend from WPU and casein. When the ethanedial content was 2 wt %, the tensile strength and elongation at break of crosslinked sheets achieved 19.5 MPa and 148% in the dry state, and 5.0 MPa and 175% in the wet state, respectively. A 2 wt % content of ethanedial plays an important role in the enhancement of mechanical properties, thermal stability, and water resistivity of the blends of WPU and casein as a result of intermolecular crosslinking. This work provided a new protein plastic with good water resistivity. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 332–338, 2004     

Miscibility and properties of blend materials from waterborne polyurethane and carboxymethyl konjac glucomannan

We prepared composite materials by blending waterborne polyurethane (WPU) and carboxymethyl konjac glucomannan (CMKGM) with CMKGM content from 15 to 80 wt % in an aqueous system. The structures and properties of the blend materials were characterized by FTIR, dynamic mechanical analysis, ultraviolet spectroscopy, scanning electron microscopy, wide‐angle X‐ray diffraction, thermogravimetric analysis, and tensile testing. The results indicated that the blend sheet with 80 wt % CMKGM exhibited good miscibility and higher tensile strength (89.1 MPa) than that of both WPU (3.2 MPa) and CMKGM (56.4 MPa) sheets. Moreover, with an increase of CMKGM content, the tensile strength, Young's modulus, and thermal stability increased significantly, attributed to intermolecular hydrogen bonding between CMKGM and WPU. Based on the experimental results, the blend materials have good, or a certain degree of, miscibility over the whole range of composition ratio of WPU to CMKGM. In addition, the blend materials exhibited organic solvent resistance. This work not only provided a simple method to prepare environmentally friendly materials, but also expanded the application of CMKGM. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 77–83, 2004     

A New Network Composite Material Based on Soy Dreg Modified with Polyurethane Prepolymer

A series of biodegradable, soy‐protein‐based, composite materials was prepared by introducing castor‐oil‐based polyurethane prepolymer (PUP) into soy dreg (SD) without the addition of plasticizers, via extrusion and a compression‐molding process. The effects of the NCO/OH molar ratio and the PUP content on the structure and properties of the resulting materials were studied by Fourier‐transform infrared spectroscopy, scanning electron microscopy, differential scanning calorimetry, dynamic mechanical thermal analysis, tensile testing, swelling experiments, and biodegradability testing. The results revealed that the ? NCO group in the PUP played a vital role in improving the compatibility and elasticity, as a result of the formation of a cross‐linking network structure with the ? NH₂, ? NH, and ? OH groups in SD containing protein and cellulose. Increasing the NCO/OH molar ratio to 2.0 resulted in an enhancement of the degree of cross‐linking, leading to a higher tensile strength (24 MPa), glass‐transition temperature (52 °C) and water‐resistivity of the composite materials. The unreacted SD also served as a filler in the cross‐linked networks and enhanced the tensile strength of the composites. The biodegradation testing showed that the composites exhibited biodegradability under the condition of fungus culture.

     

Effect of coal filler on the properties of soy protein plastics

The influence of ultrafine coal filler (UFC) content on tensile properties, water absorption, and biodegradability of soy protein plastics were investigated. The addition of UFC in the soy protein plastics, with different content of glycerol as a plasticizer, was at different ratio varying from 10:0 to 6:4. Blend sheets of the soy protein composites were prepared by the compression molding processing. The results show that, with 23.08 wt % glycerol, the tensile strength and elongation at break for the soy protein sheet with coal filler (range from 5 to 30 parts) can be enhanced as compared with nonfilled soy protein plastics. Water resistance of the soy protein plastics improves with the increase in UFC content. The derivative thermogravimetry (DTG) curves indicate a double‐stage degradation process for defatted soy flour (SPF), while three‐stage degradation process for soy plastics and the soy protein composites. FT‐IR, XPS, and SEM were applied to study the interfacial interaction between coal macromolecules and soy protein molecules in UFC filled soy protein plastics. The results demonstrated that there is strong interfacial interaction in the soy protein plastics caused by the compression molding processing. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3134–3143, 2006     

Totally bioresorbable composites prepared from poly(l‐lactide)‐co‐(trimethylene carbonate) copolymers and poly(l‐lactide)‐co‐(glycolide) fibers as cardiovascular stent material

This paper aims to evaluate the potential of totally bioresorbable composites as cardiovascular stent material. Copolymers were synthesized by ring‐opening polymerization of L ‐lactide (LLA) and 1,3‐trimethylene carbonate (TMC) with LLA‐TMC ratios of 3/1, 4/1, and 5/1 and characterized by nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), and differential scanning calorimetry (DSC). Wt. 5% of poly(L ‐lactide)‐co‐(glycolide) (PLGA) fibers are used to reinforce PTMC‐LLA copolymer matrices to prepare totally bioresorbable composites. Heat treatment under vacuum and oxygen plasma treatment are applied to improve the mechanical performance of the composites in terms of eliminating the imperfections inside, enhancing interfacial affinity, surface roughness, and enriching surface oxidative chemical bonds. After plasma treatment, the viscosity and tensile strength of the fibers decrease, but the surface chemical bonds are enriched and surface roughness is increased. The composites with 15‐min plasma‐treated fibers and 2 h heat treatment exhibit the highest tensile strength of 46 MPa, i.e., very close to that of PLLA (48 MPa), which is usually used as biodegradable stent material. Moreover, the tensile modulus of the above composite is 1711 MPa, which is only 34% of PLLA's modulus (4985 MPa). Therefore, novel composites with sufficient tensile strength and better flexibility are obtained as promising cardiovascular stent material. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers     

Soy protein‐based nanocomposites reinforced by supramolecular nanoplatelets assembled from pluronic polymers/β‐cyclodextrin pseudopolyrotaxanes

The self‐assembled rigid supramolecular nanoplatelets (SN) from Pluronic polymers with various lengths of polyethylene oxide (PEO) and β‐cyclodextrin have reinforced the soy protein isolate (SPI)‐based biodegradable plastics in terms of strength and modulus but at the expense of elongation. Meanwhile, the water resistance, which limited the application of the SPI plastics, was also enhanced. The structure and properties of nanocomposites were characterized by X‐ray diffraction, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), tensile test, and water uptake test. The low loading of nanoplatelets was able to disperse into SPI matrix homogeneously, which resulted in reinforcement in nanocomposites. With an increase of nanoplatelets loading, the repulsion between nanoplatelets and SPI matrix occurred, accompanying with the formation of rectangle objects, resulted in a decrease of mechanical performance of the nanocomposites. The nanoplatelets with longest free PEO segments produced highest strength with least loss of elongation by virtue of enhanced association with SPI matrix mediated by PEO segments. Meanwhile, the nanoplatelets with moderate length of free PEO segments showed optimal water resistance. Herein, the reinforcing function of a supramolecular nanoplatelet, similar to the structure of layered silicate, was verified. © 2007 Government of Canada. Exclusive worldwide publication rights in the article have been transferred to Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Self‐supporting‐film from starch,poly(vinyl alcohol), and glutaraldehyde: Optimization of composition using response surface methodology

Use of starch based biodegradable packaging film can partially reduce the landfilling problem from non‐biodegradable petroleum based alternatives. The aim of this work was to optimize raw material blend composition containing corn‐starch (CS), and low amount of poly(vinylalcohol) (PVA) and glutaraldehyde (GA) to produce self‐supporting‐film (SSF), using response surface methodology. Rotatable central composite design was used to evaluate the effect of CS (6.25–7.50), PVA (0.00–1.25), and GA (0.00–1.25), in g/100 mL of the blend, on tensile strength (TS), percent elongation (%El), and water vapor permeability (WVP) of the film. The most significant (p < 0.01/0.05) factors were: CS and GA for TS, CS and PVA for El, and PVA for WVP. The SSFs were thin, flexible and transparent; the optimum composition (g/100 mL) to maximize TS and El, and minimize WVP was 7.50 (CS), 0.875 (PVA), and 0.125 (GA), which produced SSF showing TS: 11.66 MPa, %El: 8.56, and WVP: 0.13 g mm/m² /kPa/h. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44436.     

Self-reinforcement of polypropylene by flow-induced crystallization during continuous extrusion

Self-reinforced polypropylene (PP) sheets have been prepared from melt flow-induced crystallization through a conical slit die fed by a conventional extruder. Their structure and properties, influenced by the die pressure ranging from 20 to 50 MPa and die outlet temperature, are studied by scanning electron microscopy observation, differential scanning calorimetry analyses, tensile strength, and light transmittance measurements. At a die outlet temperature of 162°C and a pressure above 30 MPa, conspicuous increases in the melting peak, tensile strength, and light transmittance (they can be used to characterize the self-reinforcement degree of sheet) are observed. The self-reinforcement degree, however, increases only slightly with increasing pressure as it exceeds 40 MPa. Raising the die outlet temperature from 162 to 172°C results in a further increase in the self-reinforcement degree (for example, a highest tensile strength of 288 MPa) while keeping the pressure at 40 MPa, so bulk PP materials with high properties can be produced from continuous melt extrusion under pressures lower than 40 MPa. Furthermore, the melt temperature plays an important role in determining the properties of self-reinforced polymeric materials. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67:2111–2118, 1998     

Preparation and Characterization of Bioblends from Gelatin and Linear Low Density Polyethylene (LLDPE) by Extrusion Method

Abstract

Bioblends are composites of at least one biodegradable polymer with a non-biodegradable polymer. Successful development of bioblends requires that the biodegradable polymers be compatible with other component biodegradable/synthetic (non-biodegradable) polymers. Bioblends from LLDPE and gelatin were prepared by extrusion and hydraulic heat press technique. The gelatin content in the bioblends was varied from 5 to 20 wt%. Various physico-mechanical properties such as tensile, bending, impact strength (IS), thermal ageing and soil degradation properties of the LLDPE/gelatin bioblends with different gelatin contents were evaluated. The effect of thermal ageing on mechanical properties was studied. The mechanical properties such as tensile modulus (TM), bending strength (BS), bending modulus (BM) were found to increase with increasing gelatin content up to 20 wt%, however tensile strength (TS) and elongation at break (%E _b) were decreased with increasing gelatin content. Impact strength value increased with increasing gelatin content up to 10 wt% and then decreased slightly with increasing gelatin content. The blend containing 20 wt% gelatin showed relatively better mechanical properties than other blends. The values of TS, TM,%E _b, BS, BM and IS for the bioblend with 20 wt% gelatin content are 5.9MPa, 206.3MPa, 242.6%, 12.1MPa, 8 MPa and 13.7 J/cm², respectively. Water uptake increases with increasing soaking time in water and weight loss due to soil burial also increases with increasing gelatin content in the blends but both are significantly lower than that of pure gelatin sheet. Weight loss values after thermal ageing increase with time, temperature and increasing gelatin content in the blend but are much lower than pure gelatin. Mechanical properties such as TS, TM are increased and %E _b is decreased after thermal ageing at 60°C for 30 min. Consequently, among all of the bioblends prepared in this work the blend having 20% gelatin content yields properties such that it can be used as a semi-biodegradable material.     

Mechanical properties and biodegradability of crosslinked soy protein isolate/waterborne polyurethane composites

With anionic waterborne polyurethane (WPU) as a plasticizer and ethylene glycol diglycidyl ether (EGDE) as a crosslinker, we successfully prepared crosslinked soy protein isolate (SPI) plastics. Anionic WPU was mixed with SPI and EGDE in an aqueous dispersion at room temperature. The mixed aqueous dispersion was cast and cured, and the obtained material was pickled and hot‐pressed to produce the crosslinked SPI/WPU sheets. The resulting sheets containing about 60 wt % SPI were characterized with infrared spectroscopy, scanning electron microscopy, atomic force microscopy, dynamic mechanical analysis, and tensile testing, and biodegradation testing of the sheets was performed in a mineral salt medium containing microorganisms. The results revealed that the crosslinked SPI/WPU plastics with EGDE concentrations of 2–4 wt % possessed high miscibility, good mechanical properties, and water resistivity. In addition, the crosslinked sheets could be biodegraded, and the half‐life of the biodegradation for a sheet crosslinked with 3 wt % EGDE was calculated to be less than 1 month. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 465–473, 2005     

Utilizing discarded plastic bags as matrix material for composites reinforced with chicken feathers

High‐ density polyethylene (HDPE) in used plastic bags was reinforced with chicken feathers to develop composites in an effort to add value and reduce the amount of the plastics and feathers disposed in landfills. Feathers are biodegradable, derived from renewable resource, and are inexpensive and HDPE in plastic bags is mostly discarded in landfills. Utilizing feathers as reinforcement for HDPE composites will provide an opportunity to develop environmentally friendly composites. In this research, HDPE plastic bags were reinforced with chicken feathers and the flexural, tensile and acoustic properties were studied. It was found that incorporating feathers substantially improved the flexural properties and tensile modulus. At the optimum condition, the HDPE‐feather (50/50) composites had flexural strength of 13.9 MPa and stiffness of 0.45 N/mm compared to 9.8 MPa and 0.29 N/mm for 100% HDPE. The 50/50 HDPE‐feather composite had similar tensile strength but more than twice the tensile modulus of neat HDPE. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Mechanical properties of ultrahigh-molecular-weight polyethylene fiber-reinforced PE composites

Three types of high-strength polyethylene (PE) fiber-reinforced composite sheets were made by compression molding at the vicinity of melting point of the fiber. Sheet I was molded from only PE fibers. Sheets II and III were prepared by the compression molding of PE fiber with conventional high- and low-density polyethylene films, respectively. The mechanical properties, thermal behavior, and morphologies of the sheets have been investigated and compared with each other. The tensile strength and elastic modulus of sheet III are 660 MPa and 14 GPa, respectively, which were 60 and 30 times higher than those of typical low-density PE film. Although the elastic modulus of sheet III is 6 GPa less than that of sheet II, the tensile strength of 660 MPa is highest in the three types of sheets prepared in this study. The mechanical properties of sheets II and III were about half of predicted theoretical ones. It was concluded that the interfacial adhesion between PE fiber and PE matrix was an important factor to improve the mechanical properties of this PE sheet. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 1431–1439, 1998     

Effects of molecular weight and arm number on properties of star‐shape styrene–butadiene–styrene triblock copolymer

A star‐shape styrene–butadiene–styrene triblock copolymer SBS (802) was synthesized and fractionated into four fractions coded as 802‐F1 (four arms), 802‐F2 (two arms), 802‐F3 (one arm), and 802‐F4 by repeating fractional precipitation. Their weight‐average molecular weight (M_w) was measured by size‐exclusion chromatography combined with laser light scattering to be 16.0 × 10⁴, 8.2 × 10⁴, 4.3 × 10⁴, and 1.19 × 10⁴, respectively. The samples were, respectively, compression‐molded and solution‐cast to obtain the sheets coded as 802C, 802‐F1C, 802‐F2C, and 802S, 802‐F1S, 802‐F2S. The structures and mechanical properties of the sheets were characterized by ¹H‐NMR, scanning electron microscope, wide‐angle X‐ray diffractometer, tensile testing, and dynamic mechanical thermal analysis. The results indicated that the compression‐molded 802‐F1C exhibited the higher tensile strength (σ_b, 28.4 MPa) and elongation at break (ε_b, 1610%), and its optical transmittance is much higher than those of 802C and 802‐F2C. This work revealed that the star‐shape SBS with four arms could be helpful in the enhancement of the properties as a result of good miscibility of the compression‐molded SBS sheets. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 832–840, 2005