Search

Cottonseed protein has been shown to have promising adhesive properties as an eco-friendly and effective polymeric wood adhesive. In this work, we adopted the biomimetic concept from mussel adhesio...

Storage of immunosensors has been rarely studied despite its importance for technology transfer to diagnostic companies. In this study was proposed a novel stabilizer storage solution of an electrochemical immunosensor for the detection of Salmonella. A commercial stabilizer solution for immunoglobulin was also tested for the devices. The immunosensors were kept in solution for 15, 30, 60, 90 and 120 days at refrigerated (4 ºC) and room temperature (25 ºC). There was a statistical difference (p < 0.05) between the two stabilizer solutions and the temperatures. The best condition found for the storage of the immunosensors was the formulated solution under refrigeration (4 ºC).

Due to their hygroscopic characteristics, equilibrium moisture contents of agricultural products and byproducts are important factors of their quality. Defatted cottonseed meal (CSM), washed cottonseed meal (WCSM) and cottonseed protein isolate (CSPI) can be used as energy and protein sources of animal feedstuff or industrial raw materials. Information on their moisture adsorption behaviors is needed for their storage conditions and quality control. Thus, this work measured the equilibrium moisture sorption isotherms of CSM, WCSM and CSPI, at 15, 25, 35 and 45 °C. When the moisture contents of the samples were compared at a constant temperature, the general trend of decreasing moisture content was in the order of CSPI &lt, WCSM &lt, CSM for water activity &lt, 0.6, but the trend reversed to the order of CSM &lt, CSPI for water activity &gt, 0.6. Relevant sorption isotherm equations were tested for accurate fit to the moisture adsorption data. Modelling results indicated that the G.A.B. (Guggenheim-Anderson-de Boer) model was a consistently good fit for the data among all sample types and all temperatures. This work provides some insight on designing or selecting appropriate procedures for the handling, aeration, storage and processing of these cottonseed meal products. In particular, it suggests that moisture content should be kept at around 8% for safe storage of these products at room temperature (around 25 °C) but below 5% when they are exposed to higher temperature conditions (e.g., &gt, 45 °C).

Roasting is a technological process in some food applications of agricultural products. To investigate the composition changes of the extractable functional/bioactive components of cottonseed, in this work, glandless cottonseed kernels were roasted at 110, 120, 140 and 150 °C for 15 min, respectively. The UV/vis data of the 80 % ethanol extracts found that roasting increased the level of phenolic compounds. Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry of the extracts identified about 44 % to 55 % of total formulas as potential phenolic compounds. Roasting (up to 140 °C) mainly increased carbohydrate-, lignin-, and tannin-like compounds while lipid-like compounds decreased. The compositional changes at 150 °C were less than those at 140 °C, attributed to devolatilization at the higher temperature. The information of chemical profiling of cottonseed and the roasting impact would be greatly useful in enhanced utilization of cottonseed as nutrient and functional foods or food supplements.

The interests in biobased wood adhesives have been steadily increasing in recent years. Cottonseed protein isolate has shown potential as a renewable biobased adhesives. For a better understanding ...

In order to decrease the usage of formaldehyde and petroleum-derived raw materials, there has been a lot of interest in using protein-based wood adhesives as more eco-friendly and less hazardous al...

There has been increasing interest in recent years in the use of agro-based raw materials for the production of bio-friendly and sustainable products. Plant-based proteins are among the popular materials being studied. In particular, cottonseed protein (a byproduct of cotton fiber production) is widely available and has useful properties. Although not as well-known as soy protein, cottonseed protein has been shown to be a potentially valuable raw material for numerous applications. In this review, the latest developments in isolation, composition and molecular weight, chemical and enzymatic modifications, and non-food applications are delineated. Among these applications, films and coatings, interfacial and emulsifying applications, adhesives, and bioplastics seem to attract the most attention. A particular effort has been made to cover the literature on these topics in the past 10 years.

This special issue of the Journal of Agricultural and Food Chemistry (JAFC) is a highlight of the Agricultural and Food Chemistry Division (AGFD) technical program at the 258th National Meeting of the American Chemical Society (ACS) in San Diego, CA, U.S.A., on August 25-29, 2019. At the conference, AGFD had 44 oral sessions at 19 symposia and 100 poster presentations with more than 400 abstract submissions. The technical program covered a broad range of current research and development topics in agricultural and food chemistry, including bioactive food components, diet and human nutrition, utilization of agricultural materials in food systems, food packaging, nanotechnology, and food safety, as well as several special award symposia. This is the first JAFC special issue that highlights an ACS national meeting program with joint efforts from AGFD.

The purpose of this work was to explore the possibility of using cotton gin trash (CGT) as an inexpensive and biodegradable filler for poly(vinyl alcohol) (PVOH). CGT was milled and screened to give fine particles, and the particles less than 150 um in size were used together with three PVOH polymers (with 1–20% vinyl acetate levels) to form composites. Up to 60% by weight of CGT could be incorporated into PVOH to form composite films. Relative to PVOH, these PVOH/CGT films showed reduced tensile strength and elongation at break but enhanced Young’s modulus. CGT was chemically modified through acetylation and succinylation; however, no significant improvement in mechanical properties was observed with these modifications, although acetylated CGT did exhibit somewhat improved elongation at break relative to unmodified CGT for the two PVOH polymers with higher vinyl acetate contents. Thus, for PVOH applications that need reduced cost but can tolerate decreased tensile strength and elongation, cotton gin trash can be used as a cost-effective filler.

Xylan is a major type of hemicellulose that has attracted a lot of research and development activities. It is often derivatized in order to improve its properties. In the literature, hydrophobic modification of polymers is often used to produce surfactant-like materials and associative thickeners. In this work, we have derivatized xylan with alkyl ketene dimer (AKD) and two types of alkenyl succinic anhydrides (ASAs). The xylan-AKD derivatives have been made at 90 &deg, C, using dimethyl sulfoxide as solvent and 4-dimethylaminopyridine as promoter. Samples with degrees of substitution (DS) up to 0.006 have been produced. The xylan-ASA derivatives have been synthesized at 120 &deg, C in dimethyl sulfoxide with DS up to 0.105&ndash, 0.135. The structures of these products have been confirmed with NMR and FT-IR. These xylan derivatives increase the structural diversity of xylan and provide additional options for people seeking to use hydrophobically modified polysaccharides in their applications.

Iron nanoparticles (FeNP) present excellent magnetic properties and chemical stability, and for this reason, they are often configured into materials for a variety of potential uses in medical, biotechnological, and other applications. In this work, iron oxide nanoparticles functionalized with galactomannan (FeNP/Gal) from Caesalpinia pulcherrima were synthesized and submitted to characterization and evaluation of the cytotoxic activity. The functionalized nanoparticles were synthesized by co-precipitation and subjected to a process of surface modification with galactomannan and epichlorohydrin. These nanomaterials were characterized using infrared spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential thermogravimetric analysis (DTA), and scanning electron microscopy (SEM). 1D and 2D nuclear magnetic resonance (NMR) spectroscopy were also used in the structural analysis of the galactomannan. In addition, in vitro study was carried out to evaluate the cytotoxic activity of the FeNP/Gal nanoparticles on human cells of the HEK-293 strain (ATCC® CRL-1573). The FeNP/Gal nanoparticles had an average diameter of 13 ± 2 nm as opposed to 11 ± 2 nm for unreacted FeNP. The infrared spectrum of the FeNP/Gal nanoparticles presents characteristic absorbance bands of their chemical constituents, confirming that the iron oxide nanoparticles were functionalized with galactomannan. The cytotoxicity assay for the FeNP/Gal nanoparticles did not show significant cytotoxicity against HEK 293-Human embryonic kidney cell lines below 800 µg/mL However, this study points out the possibility of using hemicellulose and other plant-based polysaccharides to produce nanostructured materials for ​​tissue engineering and other biomedical applications.

New functional foods and beverages can be developed using bioactive compounds present in pequi oil. Complex coacervation is an encapsulation method used for preserving bioactive molecules, especially those that are hydrophobic or sensitive to high temperatures. The objective of this work was to produce and characterize pequi oil microparticles using cashew gum/gelatin matrix (CG/GE) through complex coacervation. Gum Arabic (GA) was also studied in comparison with CG. The coacervation process was performed without pequi oil to determine the ideal proportions of the matrix components, followed by the embedding of the oil inthe microparticles for evaluation. Satisfactory microparticles were produced at pH 4.5 in the weight ratios of CG/GE = 2:1 and GA/GE = 1:3. Pequi oil release was greater in acidic pH, especially at pH 2 for the CG/GE matrix. The encapsulation efficiency for CG/GE and GA/GE was 72.53% (±4.80) and 82.77% (±6.09), respectively . The results showed that the CG/GE combination seemed very promising as anencapsulation matrix, especially for food applications involving pH values higher than 3.

Currently, there is an increasing interest in the use of biopolymers in industrial applications to replace petroleum-based additives, since they are abundantly available, renewable and sustainable. Cottonseed protein is a biopolymer that, when used as a modifier, has shown improved performance for wood adhesives and paper products. Thus, it would be useful to explore the feasibility of using cellulose nanomaterials to further improve the performance of cottonseed protein as a paper strength agent. This research characterized the performance of cottonseed protein isolate with/without cellulose nanofibers (CNFs) and cellulose nanocrystals (CNCs) to increase the dry strength of filter paper. An application of 10% protein solution with CNCs (10:1) or CNFs (50:1) improved the elongation at break, tensile strength and modulus of treated paper products compared to the improved performance of cottonseed protein alone. Further analysis using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) indicated that the cottonseed protein/nanocellulose composites interacted with the filter paper fibers, imparting an increased dry strength.

Cottonseed protein is a potential alternative to formaldehyde-based adhesives as a renewable resource without negative environmental impact in use. Like other protein-based adhesives, unmodified cottonseed protein isolate needs improved water resistance. Thus, in this work, the effects of phosphoric acid (H3PO4), dipotassium hydrogen phosphate (K2HPO4), calcium oxide (CaO), and calcium hydrogen phosphate (CaHPO4) at four concentrations (i.e., 20, 40, 60, and 80 mM) on the adhesive strengths of cottonseed protein isolate were evaluated. Compared with control (protein without modifiers), H3PO4 (20 and 40 mM) increased dry, wet, and soaked strength by 20–30, 72–88, and 24–30%, K2HPO4 (40 and 60 mM) by 8–22, 2–10, and 1–8%, CaO (20 and 40 mM) by 8–16, 11, and 6%, and CaHPO4 (40, 60, and 80 mM) by 12–26, 6–13, and 7–14%, respectively. Cottonseed protein with 40 mM H3PO4 had the best adhesive performance, especially water resistance (88% higher in the wet strength than control), due to the increased crosslinking at its isoelectric point caused by acidity of H3PO4 (pH, 4.13). Solid state 13C nuclear magnetic resonance spectroscopic analysis showed that the amino groups interacted with these P compounds in the blending adhesives. Finally, an optimized protein adhesive preparation was applied to bond 3-ply pine plywood. The water resistance of these 3-ply strips passed the industrial soak test as Type II plywood used for hardwood and decorative plywood, indicating that the adhesive under optimal conditions can be used as a green and environment-friendly adhesive resource in wood industry.

There is current interest in active packaging, where the packaging material exhibits desirable functions in addition to containment of product. One of these functions is to reduce the oxygen content in the package in order to minimize product oxidation and spoilage, and prolong product shelf-life. In this work, we have developed novel nanocomposites, comprising cellulose nanocrystals and Pd nanoparticles embedded in an ethylene–vinyl alcohol copolymer (EVOH). The nanocellulose is a critical component in the nanocomposite because it acts not only as reducing agent for PdCl2 but also as support for the dispersion of Pd nanoparticles on EVOH film and enhances the physical properties of the EVOH. Pd nanoparticles react with oxygen to serve as oxygen scavenger. The cellulose nanocrystals have also been optionally oxidized, and the increased presence of carboxyl groups favored a better distribution of the Pd nanoparticles, thereby enabling improved oxygen absorption. These features make the nanocomposites promising candidates as active packaging materials. Included in this work are the preparation and the characterization of these materials.

Recently, there has been an increasing trend toward replacing conventional fossil-based plastics with bioplastics that are eco-friendly and biodegradable. In this work, blends of polycaprolactone (...

High performance nanocomposites with good interfacial miscibility and phase separated morphology have received a lot of attention. In this work, cellulose nanocrystals (CNCs) were first grafted with hydrophobic poly(methyl methacrylate) (PMMA) chains to produce modified CNCs (PMCNCs) with increased thermal stability. Such surface-tailored CNCs effectively influenced the phase morphology and improved the mechanical properties of poly(butyl acrylate-co-MMA) (PBA-co-PMMA) nanocomposites. Morphological analysis indicated the presence of microphase separation in PMCNCs/PBA-co-PMMA nanocomposites with PBA as the soft domain and PMMA as well as CNCs as the hard domain. The nanocomposites with 10 wt% PMCNCs/PBA-co-PMMA showed increases in Young’s modulus of more than 20-fold and in tensile strength of about 3-fold compared to those of the unmodified PBA-co-PMMA copolymer. Therefore, the PMCNCs played a crucial role in controlling the interfacial miscibility and tuning the phase morphology of the nanocomposites. It is also essential to understand the role played by microphase separation in achieving nano-scaled morphological control and in fine-tuning the resultant composite properties.

Cellulose is often described as a mixture of crystalline and amorphous material. A large part of the general understanding of the chemical, biochemical and physical properties of cellulosic materials is thought to depend on the consequences of the ratio of these components. For example, amorphous materials are said to be more reactive and have less tensile strength but comprehensive understanding and definitive analysis remain elusive. Ball milling has been used for decades to increase the ratio of amorphous material. The present work used 13 techniques to follow the changes in cotton fibers (nearly pure cellulose) after ball milling for 15, 45 and 120 min. X-ray diffraction results were analyzed with the Rietveld method; DNP (dynamic nuclear polarization) natural abundance 2D NMR studies in the next paper in this issue assisted with the interpretation of the 1D analyses in the present work. A conventional NMR model’s paracrystalline and inaccessible crystallite surfaces were not needed in the model used for the DNP studies. Sum frequency generation (SFG) spectroscopy also showed profound changes as the cellulose was decrystallized. Optical microscopy and field emission-scanning electron microscopy results showed the changes in particle size; molecular weight and carbonyl group analyses by gel permeation chromatography confirmed chemical changes. Specific surface areas and pore sizes increased. Fourier transform infrared (FTIR) and Raman spectroscopy also indicated progressive changes; some proposed indicators of crystallinity for FTIR were not in good agreement with our results. Thermogravimetric analysis results indicated progressive increase in initial moisture content and some loss in stability. Although understanding of structural changes as cellulose is amorphized by ball milling is increased by this work, continued effort is needed to improve agreement between the synchrotron and laboratory X-ray methods used herein and to provide physical interpretation of the SFG results.

Indicadores colorimetricos sao sistemas que podem facilmente ser introduzidos a embalagens, a fim de informar ao consumidor a cerca da qualidade do produto. Amonia e gerada durante a deterioracao do pescado e pode ser monitorada por meio de indicadores colorimetricos. Neste trabalho objetivou-se eletrossintetizar filmes de polianilina para a deteccao da amonia por meio da mudanca de cor. Filmes foram eletrodepositados por voltametria ciclica e cronoamperometria em meio acido sobre superficie de ITO. O filme crescido por voltametria ciclica apresentou uma morfologia mais plana e um limite de deteccao de 0,05 mol L -1 . O filme crescido por cronoamperometria apresentou uma morfologia de rede interconectada, um limite de deteccao de 0,015 mol L −1 e uma mudanca de cor verde para azul mais perceptivel visualmente. Assim, recomenda-se produzir o filme por cronoamperometria para a producao de um indicador colorimetrico para deteccao da amonia em funcao do limite de deteccao e da melhor visualizacao da mudanca de coloracao.

Water washed cottonseed meal (WCSM) is an excellent bio-adhesive resource because of its cost-effective extraction process and environmentally friendly performance. To evaluate the effects of protein content on the adhesive performance of cottonseed meal-based adhesives, we reconstituted cottonseed meal products with protein contents ranged from 34.9% to 94.8% by blending different amounts of WCSM, cottonseed protein isolate (CSPI), and residues after protein extraction (CSIR). Their physicochemical properties and three types of adhesive strengths (dry, wet, and soaked) were measured with press temperatures at 100, 150 and 170 °C. The morphological and rheological data showed that the low-protein-content adhesives with a high amount of residual cotton hull and fiber possessed poor spreadability and adhesive strength. Molecular and thermal analysis suggested that protein ratio had a stronger influence than press temperature to thermal property and adhesive strength. With these data, multiple linear regression models were established, providing analytical tools to predict the bonding strength affected by protein content and press temperature in cottonseed meal-based adhesives. On the other hand, the blends with 65–70% of protein content demonstrated the bonding performance and flowability comparable to highest protein product CSPI (94.8% protein) within the acceptable standard deviations. Thus, these observations and data could be helpful in set-up of industrial standard requirements and quality control for protein content in cost-effective adhesive-grade WCSM products.

This study focuses on the production and characterization of electrosprayed cashew gum (CG) microparticles that encapsulate β-carotene. CG is an inexpensive, non-toxic polysaccharide obtained from Anacardium occidentale trees. Encapsulation of β-carotene in CG was performed by electrospraying from two emulsion formulations (water : oil ratios 80:20 and 90:10 (v/v)) in which the dispersed phase consisted of β-carotene dissolved in castor oil, and the continuous phase was a CG aqueous solution. Spherical particles with smooth surface and medium size between 3 and 6 μm were obtained. The particles produced from the 90:10 (v/v) emulsion showed a loading capacity of 0.075 ± 0.006 % and a minor amount of extractable β-carotene, 10.75 ± 2.42 %. ATR-FTIR confirmed the absence of interaction between the particles’ components. CG demonstrated to offer thermoprotection, and photoprotection for short periods of time. These results make CG a viable candidate to encapsulate bioactive compounds via electrospraying for agricultural, food and pharmaceutical applications., This work was supported in part by the U.S. Department of Agriculture, Agricultural Research Service.

Cotton is one of the most important and widely grown crops in the world. Understanding the synthesis mechanism of cotton fiber elongation can provide valuable tools to the cotton industry for improving cotton fiber yield and quality at the molecular level. In this work, the surface and thermal characteristics of cotton fiber samples collected from a wild type (WT) and three mutant lines (Li1, Li2-short, Li2-long, Li2-mix, and liy) were comparatively investigated. Microimaging revealed a general similarity trend of WT ≥ Li2-long ≈ Li2-mix &gt, Li1 &gt, Li2 short ≈ liy with Ca detected on the surface of the last two. Attenuated total reflectance Fourier transform infrared (ATR FT-IR) spectroscopy and thermogravimetric measurements also showed that Li2-short and liy were more similar to each other, and Li2-long and Li2-mix closer to WT while Li1 was quite independent. FT-IR results further demonstrated that wax and amorphous cellulose were co-present in fiber structures during the fiber formation processes. The correlation analysis found that the FT-IR-based maturity parameter was well correlated (p ≤ 0.05) to the onset decomposition temperature and all three weight-loss parameters at onset, peak, and end decomposition stages, suggesting that the maturity degree is a better parameter than crystallinity index (CI) and other FT-IR parameters that reflect the thermal stability of the cotton fiber. In summary, this work demonstrated that genetic mutation altered the surface and thermal characteristics in the same way for Li2-short and liy, but with different mechanisms for the other three mutant cotton fiber samples.

Novel nanocomposite hydrogels were successfully prepared by blending and crosslinking sodium alginate (SA), poly(vinyl alcohol) (PVA) and cellulose nanofibers (CNFs) in the presence of a fertilizer formulation containing nitrogen (N), phosphorus (P) and potassium (K). The hydrogels had a macroporous flexible core and a microporous semi- interpenetrating polymer network (IPN) shell. The crystalline nature of the NPK chemicals was retained in the hydrogel nanocomposite network. Furthermore, the SA/CNF/PVA-based hydrogels showed a higher water-retention capacity in both deionized water and mixed soil. The swelling behavior in various physiological pH, salt and alkali solutions exhibited good sensitivity. The NPK release from SA/CNF/NPK and SA/CNF/PVA/NPK hydrogels was controlled by Fickian diffusion in both water and soil based on the Korsmeyer-Peppas release kinetics model (n

Cashew gum (CG) shows promise of being useful as an agro-based raw material for the production of eco-friendly and biodegradable polymers. In this work, we modified this water-soluble polymer with alkenyl succinic anhydride in order to attach a hydrophobic group to it. The modification used two reagents: octenyl succinic anhydride and tetrapropenyl succinic anhydride. Reactions were conducted at 120 &deg, C using dimethyl sulfoxide as a solvent, with conversions better than 88%. Samples with degrees of substitution (DS) between 0.02 and 0.20 were made. The resulting polymers were characterized using 1H NMR, 13C NMR, FTIR, TGA, and GPC. The addition of the hydrophobe decreased the affinity of cashew gum for water absorption. Hydrophobically modified polysaccharides are often used as polymeric emulsifiers, thickeners, and compatibilizers, we anticipate that these new hydrophobically modified CGs may be used for the same applications.

Polyhydroxyalkanoates (PHAs) are considered promising “green” alternatives to synthetic polymers because they are bio-derived, biodegradable and biocompatible. The properties of bacterial PHA copolymers depend on their microstructures, which can be modified with the use of different fermentation processes and feed materials. Thus, it is desirable to have an improved testing method for the determination of PHA microstructures. In this work, a detailed NMR analysis of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) microstructure was made. Previously only two of the hydroxyvalerate 13C NMR peaks have been assigned at the triad level. In this work, three of the 13C hydroxyvalerate peaks and two of the hydroxybutyrate peaks were found to be split into four peaks each due to comonomer sequence effects. Using eight copolymer samples with a wide compositional range, we were able to assign all these peaks to B-centered and V-centered triad sequences. Through curve deconvolution, the triad intensities were determined. These triad sequence intensities can then be analyzed via both the first-order Markovian and two-component Bernoullian models to obtain more in-depth information on copolymer composition and comonomer reactivities., The authors would like to thank the Spanish Ministry of Science and Innovation (MICI) through the RTI2018-097249-B-C21 program number and the EU H2020 YPACK (reference number 773872) for funding.

As the 2019, 2020, and 2021 presidents of the American Chemical Society (ACS), it is our pleasure to extend our well-wishes to the Federation of Asian Chemical Societies (FACS) in the inaugural issue of AsiaChem. ACS is proud to support the efforts of partner chemical societies around the world, particularly regional collaborators like FACS. The creation of this publication is a monumental step for FACS and we are pleased to be a part of this historic edition.

There is increasing interest in agro-based, biodegradable and eco-friendly wood adhesives as partial replacements for petroleum-based adhesives. In this work, we studied the adhesion of cottonseed ...

In this study, a polysaccharide and a protein were combined to form a polyblend that can be used for food packaging. Cashew gum (CG) and gelatin (G) films were generated by the casting method with the help of the central composite rotational design. When filmogenic solutions of 2.5–7.5 g of G and CG were dissolved in 100 mL water with 10% glycerol, the resulting films were compact and homogeneous with no pores present. Different CG/G ratios were examined for water vapor permeability (WVP), thickness, solubility, mechanical and thermal properties, surface morphology, and biodegradability. The results showed that at around 1:1 CG/G weight ratio the solubility decreased, reaching the minimum value at the CG composition of 45%. The blend of 50/50 CG:G showed the best WVP (1.16 g mm k Pa−1 h−1 m−2). For elongation at break, the combination of 5 g CG and 2.5 g G provided the best results with over 100% elongation. The films were shown to be easily biodegradable, producing as much CO2 as starch during the 22 days of an aerobic biodegradability test.

Acylation of polysaccharides is a commercially important reaction and is usually performed in a process involving the polysaccharide, an acid anhydride, and an inorganic acid. As an alternative to inorganic acid, many catalysts, including some metal chlorides, have been previously reported as catalysts. In this work, we took a more comprehensive look at several metal chlorides to observe trends and reactivities among them, particularly relating to reaction temperature, time, and amount of acetic anhydride used. Iodine was also included for comparison. Almost all the metal chlorides studied were found to be active as catalysts for the acetylation of starch under suitable reaction conditions. However, each metal chloride had a somewhat different reactivity with a different optimal temperature needed for satisfactory reactions to take place. The molecular weight of the starch acetate products decreased in all cases observed. The reactivity trends among the metal halides seemed to correlate both with ...

Although hemicellulose is found widely in nature, it is currently under-utilized as a raw material for commercial applications. It would be desirable to find new uses for hemicellulose in order to add value to this agro-based material. A common type of hemicellulose is xylan, which is found in a number of wood species and in cotton. In this work we prepared cationic and anionic xylan derivatives and characterized them by 13C NMR, FT-IR, size exclusion chromatography (SEC), thermal analysis, and rheology. In particular, the 13C NMR spectra of carboxymethyl xylan (CMX) and quaternary ammonium-adducted xylan (QAX) were fully assigned with the help of samples with different degrees of substitution. SEC indicated that the beechwood xylan showed a bimodal molecular weight distribution, but with derivatization the distribution tended to become unimodal. Thermal analysis and rheology studies did not uncover any surprises; the solution of xylan and its derivatives exhibited mostly Newtonian behavior. The blends of CMX and QAX produced a precipitate at almost all ratios, indicating the formation of a polyelectrolyte complex. When cationic and anionic xylan samples were added together to paper, the paper dry strength increased. Thus, the combination of cationic/anionic xylan may be of interest in selected applications.

Nonwoven fabrics have grown in popularity in recent years due to their overwhelming usage in a wide range of consumer products. Cotton-based nonwovens are of particular interest because of their ability to be recycled and reused, resulting in a more environmentally friendly product compared to their petroleum-based counterparts. The current research characterized the use of cottonseed protein as an additive to increase the dry strength of cotton-based nonwovens. The tensile strength of nonwovens was found to increase as the concentration of protein applied was increased. At 11% protein concentration, the tear strength and burst strength increased significantly (relative to the nonwoven by itself) by 288% (machine direction) and 295%, respectively. Further characterization by thermogravimetric analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy suggested that cottonseed protein interacted with the cotton fiber in the nonwoven fabric to produce the increased dry strength.