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A novel route to adamantane substituted diene copolymers is demonstrated using emulsion polymerization, with an improved monomer synthesis. Heterogenous dehydration of 2‐(1‐adamantyl)‐3‐buten‐2‐ol using Amberlyst®‐15 cationic exchange resin at ambient temperature gave 2‐(1‐adamantyl)‐1,3‐butadiene (1) in excellent yield and presents an attractive alternative monomer synthesis route. Emulsion polymerization of 1 and mixtures of 1 and isoprene was carried out at room temperature using redox pair, hydroperoxide initiator. All poly(1) and poly(1‐ran‐isoprene) samples were soluble in common organic solvents and exhibited high 1,4‐microstructure. A continuous increase in glass transition temperature from −63 to 172°C was observed by increasing the ratio of 1 in the comonomer feed of poly(1‐ran‐isoprene), and Tg values were in good agreement with the Fox equation. After complete hydrogenation to poly(1‐vinyladamantane‐alt‐ethylene‐ran‐propylene‐alt‐ethylene), a continuous increase in Tg was observed from −55 to 152°C. The high solubility and improved access to 2‐(1‐adamantyl)‐1,3‐butadiene opens the door to exploration of diene polymers with enhanced high temperature properties. [ABSTRACT FROM AUTHOR]

Corrugated cardboard (CCB) comprises a substantial portion of municipal solid waste, of which ~5% is wax coated CCB (WCCB) to enhance its performance. WCCB cannot be recycled, making it a suitable resource to recover wax and produce char. The WCCB was characterized for its extractable wax, lignin, and carbohydrate contents and by thermogravimetric analysis to study its thermal degradation behavior. WCCB was preliminarily examined by pyrolysis‐gas chromatography–mass spectrometry to determine product composition. WCCB samples were then pyrolyzed in auger and tube reactors at 450, 500, and 550°C, and their pyrolysis wax‐oil and char products characterized. WCCB and char were subjected to proximate, ultimate, surface area, analyses. The highest char yield was 36% at 450°C, and the highest wax‐oil yield was 53% at 550°C in the tube reactor. The wax‐oil fraction contained mainly alkanes, alkenes, and dienes (C9–C36), and chain length decreased with pyrolysis temperature. This wax fraction could be recovered and used as bunker fuel (C12–C40) or further converted to diesel (C10–C20). [ABSTRACT FROM AUTHOR]

Peas are an underutilized crop that do not require allergen labeling and are rarely genetically modified. Peas contain less protein than soy and vary in protein composition. Because peas contain more starch than soy and less lipids, an alternative procedure for pea tofu production needs to be developed to prevent excessive starch gelatinization while promoting curd development. To accomplish this, a response surface model design was utilized to determine optimal oil addition, cook time, and salt concentration. Treatment ranges were from 0.0% to 4.2% for oil addition, 60–134 min for cook time, and 5.0%–9.2% for MgCl2 addition. Treatments had varying effects on tofu texture. Cook time was directly proportional to the hardness and could be used to match the soft, firm, and extra firm texture targets of conventional soy tofu. Protein secondary structure was not related to gel strength, indicating a system with synergies between multiple components other than protein. This research will help satisfy the growing demand for alternatives to soy‐based foods. [ABSTRACT FROM AUTHOR]

Four different morphological plant parts of Musa spp. (banana and plantain) residues obtained from the rainforest belt of Nigeria were investigated. The study undertook Fourier transform infrared (FTIR) spectroscopy, X‐ray diffraction (XRD), and physicochemical analysis. The total crystallinity (TCI) and lateral order (LOI) indices showed that the cellulose crystallinity for banana pseudo‐stem (LOI‐5.18; TCI‐0.37) and banana rachis (LOI‐4.25; TCI‐0.44) were relatively higher than for the banana (LOI‐0.11; TCI‐0.20) and plantain (LOI‐0.17; TCI‐0.18) peels. The XRD analysis confirmed the presence of starch in the peels and cellulose I in the structural samples (rachis and the pseudo‐stem). A further demonstration of the marked differences between the morphological parts of Musa spp was highlighted in the analysis of the FAMES extract as banana peels (21 mg g−1 of biomass) and plantain peels (20 mg g−1 of biomass) had the highest quantity of palmitic acids whereas the eicosanoic, behnic, and lignoceric acids were absent in the peels. The relatively high ash content (≤12.30 wt %) in the Musa spp. samples may necessitate a pretreatment process prior to deployment for bioenergy or chemical extraction purposes. Furthermore, kinetic studies, which involved differential Friedman's and integral Flynn–Wall–Ozawa techniques, and analytical pyrolysis of the residues were undertaken. The activation energy varied continuously with conversion; reaching a peak of >290 kJ/mol. The analytical pyrolysis detected acids, sugar derivatives, and phenolic compounds in significant concentrations for all biomass samples. © 2018 American Institute of Chemical Engineers Environ Prog, 37: 1901–1907, 2018 [ABSTRACT FROM AUTHOR]

The properties of old newspaper fibers (ONPF) reinforced recycled polypropylene (rPP) composites (ONPF/rPP) have been studied. The effect of alkaline and neutral deinking treatments of ONPF was investigated. The tensile and flexural strength of ONPF/rPP composites were significantly improved when compared to the neat rPP. Composites from neutral deinked fibers showed slightly better mechanical strength than that reinforced by alkaline deinked fibers. The effect of the ONPF deinking treatment on the water absorption of the composites was notable. Thermogravimetric analysis revealed that deinked ONPF/rPP composites had lower thermal stability. Differential scanning calorimetry showed deinking treatment reduced the degree of crystallinity of composites as compared to the undeinked composites. X‐ray diffraction was used to characterize the crystallization structures of composites. Scanning electron microscopy micrographs of 20 wt% ONPF/rPP composites showed well fiber dispersion in the matrix. Interfacial adhesion was decreased in the deinked samples due to removal of ink particles. POLYM. COMPOS., 39:3537–3544, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

This study investigated the production of crude bio-oils from three laboratory cultivated and two commercial grade algal biomass sources via hydrothermal liquefaction (HTL) process. Results demonstrated the crude bio-oils generated from laboratory cultivated algae fed 5% anaerobic digestion effluent as sole nutrient source have similar thermochemical characteristics as comparison with that of derived from commercial algae. The HTL conditions were optimized (300°C for 20 min) and the generated bio-oils were characterized by gas chromatography mass spectrometry, Fourier transform infrared spectroscopy, and electrospray ionization-mass spectrometry analyses and simulated distillation by thermogravimetric analysis. The bio-oil yields were between 28 and 41%. The bio-oils were mainly comprised of fatty acids and alkanes. These bio-oils can be further upgraded and refined into value added transportation fuels and chemicals. © 2017 American Institute of Chemical Engineers Environ Prog, 36: 781-787, 2017 [ABSTRACT FROM AUTHOR]

BACKGROUND: In 2012, 9.3 million head of dairy cows in the USA produced an estimated 20 million metric tons of manure solids, but little value was gained from this manure. There is a pressing need to enhance manure resource recovery efforts, as dairy manure has potentially significant environmental impacts. This study evaluated components of an integrated suite of biological processes designed to maximize resource recovery from dairy manure, in which algae grown on polyhydroxyalkanoate (PHA) production effluent (PHA-algae) were fermented and anaerobically digested to determine process impacts. RESULTS: A 10% PHA-algae supplement produced 11% more volatile fatty acids (VFA) during fermentation and 11% more methane during anaerobic digestion (AD) (vs. dairy manure); the PHA-algae biogas also contained a higher percentage (62.7 vs. 59.1%) of methane than manure biogas. Algal augmentation exhibited no negative effect on fermenter or AD operation. Quantitative polymerase chain reaction (PCR) showed that the ADs contained substantial populations of both acetoclastic and hydrogenotrophic methanogens, which, given the heterogeneous substrate, enhanced process stability. There were significant differences between PHA-algae batches, and large quantities of COD were released during algae freezing. CONCLUSION: PHA-algae yielded more VFA during fermentation, and a more methane-rich biogas following AD than dairy manure. A 10% PHA-algae supplement caused no process disturbance in normal manure flora. [ABSTRACT FROM AUTHOR]

ABSTRACT The melting, isothermal and nonisothermal crystallization behaviors of poly(3-hydroxybutyrate) (PHB) have been studied by means of temperature modulated differential scanning calorimetry (TMDSC) and conventional DSC. Various experimental conditions including isothermal/annealing temperatures (80, 90, 100, 105, 110, 120, 130, and 140°C), cooling rates (2, 5, 10, 20, and 50°C/min) and heating rates (5, 10, 20, 30, 40, and 50°C/min) have been investigated. The lower endothermic peak ( Tm1) representing the original crystals prior to DSC scan, while the higher one ( Tm2) is attributed to the melting of the crystals formed by recrystallization. Thermomechanical analysis (TMA) was used to evaluate the original melting temperature ( Tmelt) and glass transition temperature ( Tg) as comparison to DSC analysis. The multiple melting phenomenon was ascribed to the melting-recrystallization-remelting mechanism of the crystallites with lower thermal stability showing at Tm1. Different models (Avrami, Jeziorny-modified-Avrami, Liu and Mo, and Ozawa model) were utilized to describe the crystallization kinetics. It was found that Liu and Mo's analysis and Jeziorny-modified-Avrami model were successful to explain the nonisothermal crystallization kinetic of PHB. The activation energies were estimated in both isothermal and nonisothermal crystallization process, which were 102 and 116 kJ/mol in respective condition. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42412. [ABSTRACT FROM AUTHOR]

ABSTRACT Poly(3-hydroxybutyrate) (PHB) and poly( l-lactic acid) (PLLA) were individually cross-linked with dicumyl peroxide (DCP) (0.25-1 wt %) by reactive melt processing. The cross-linked structures of the polymer gel were investigated by nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopies. The size of the polymer crystal spherulites, glass transition temperature ( Tg), melting transition temperature ( Tm), and crystallinity were all decreased as a result of cross-linking. Cross-linking density (ν e) was shown to increase with DCP concentration. Based on parallel plate rheological study (dynamic and steady shear), elastic and viscous modulus ( G″ and G′), complex viscosity (η*) and steady shear viscosity (η) were all shown to increase with cross-linking. Cross-linked PHB and PLLA showed broader molar mass distribution and formation of long chain branching (LCB) as estimated by RheoMWD. Improvements in melt strength offer bioplastic processors improved material properties and processing options, such as foaming and thermoforming, for new applications. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41724. [ABSTRACT FROM AUTHOR]

ABSTRACT Lignin-based thermal responsive dual shape memory copolymeric elastomers were prepared with a highly branched prepolymer (HBP, A2B3 type) via a simple one-pot bulk polycondensation reaction. The effect of fractionated lignin type (with good miscibility in the HBP) on copolymer properties was investigated. The thermal and mechanical properties of the copolymers were characterized by DMA, DSC, and TGA. Tensile properties were dominated by HBP <45% lignin content while lignin dominated >45% content. The copolymers glass transition temperature ( Tg) increased with lignin content and lignin type did not play a significant role. Thermally stimulated dual shape memory effects (SME) of the copolymers were quantified by cyclic thermomechanical tests. All copolymers had shape fixity rate >95% and >90% shape recovery for all compositions. The copolymer shape memory transition temperature ( Ttrans) increased with lignin content and Ttrans was 20°C higher than Tg. Lignin, a renewable resource, can be used as a netpoint segment in polymer systems with SME behavior. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41389. [ABSTRACT FROM AUTHOR]

ABSTRACT Lignin based thermal-responsive elastomers were produced by a melt polycondensation reaction with a long alkyl chain hyperbranched poly(ester-amine-amide) (B3-A2-CB31). The effect of lignin content on elastomers properties was investigated. The thermal and mechanical properties of the copolymers were characterized by DMA, DSC, and TGA. The morphology of the copolymer was examined by SEM. Tensile properties were dominated by HBP <25% lignin content while lignin dominated >25% content. The copolymers glass transition temperature ( Tg) increased with lignin content. The elastomer with 30% lignin content demonstrated optimal mechanical properties (tensile strength 5.3 MPa, Young's modulus 8.9 MPa, strain at break 301%, and toughness 1.03 GPa). Thermally stimulated dual shape memory effects (SME) of the copolymers were quantified by cyclic thermomechanical tests. The transition temperature ( Ttrans) of the polymer was able to be controlled (room to body temperature) by varying the amount of lignin added which broadens the range to medical applications. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41103. [ABSTRACT FROM AUTHOR]

A novel silica nanospring (NS) supported cobalt catalyst for Fischer-Tropsch synthesis (FTS) was synthesized and investigated, and the results were compared with those of a conventional cobalt catalyst. The NS catalyst was prepared using deposition of Co followed by thermal assisted reduction and characterized by scanning electron microscopy-energy dispersive spectroscopy, transmission electron microscopy, N2 physisorption, X-ray powder diffraction, X-ray photoelectron spectroscopy, and H2-temperature programmed reduction. FTS performance was evaluated in a quartz fixed-bed microreactor (230°C, H2:CO ratio 2:1), and the products were trapped and analyzed with gas chromatography-thermal conductivity detector (GC-TCD, gases) and gas chromatography-mass spectrometry (GC-MS, semivolatiles) to determine the percentage of CO conversion and selectivity. Semivolatile products from both catalysts were C6-C18 hydrocarbons. Even though the NS FTS catalyst was not fully reduced during the activation period it still showed higher FTS activity than the conventional catalyst, which is attributed to the higher accessibility of the gases to the Co on the NS surface. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 693-698, 2014 [ABSTRACT FROM AUTHOR]

ABSTRACT The bioplastic poly(3-hydroxybutyrate- co-3-hydroxyvalerate) (PHBV), was isolated from a bioreactor using mixed microbial consortia fed volatile fatty acids (VFA), from fermented dairy manure, as the carbon source. The molar fraction of 3-hydroxyvalerate (3HV) amounted to 0.33 mol mol−1 for two isolated PHBV samples as determined by GC-MS and 1H-NMR spectroscopy. The chemical, thermal, and mechanical properties were determined. The PHBVs had relatively high Mw (∼790,000 g mol−1). Only a single glass transition temperature ( Tg) and melting point ( Tm) were observed. Isolated PHBVs exhibited good flexibility and elongation to break as compared with commercial PHBVs with lower HV. The diad and triad sequence distributions of the monomeric units were determined by 13C-NMR spectroscopy and followed Bernoullian statistics suggesting that the PHBVs were random. The PHBV sequence distribution was also characterized by electrospray ionization-mass spectrometry (ESI-MSn) after partial alkaline hydrolysis to oligomers showing a random 3HV distribution. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40333. [ABSTRACT FROM AUTHOR]

ABSTRACT Polyurethanes (PU) were synthesized from lignin by first preparing a prepolymer from esterified sugar-based trihydroxyl compound xylaric acid and a 20 mol % excess of methylene diphenyl diisocyanate. The prepolymer was crosslinked with 5, 10, and 15 wt % of an industrial soda lignin, and polyethylene glycol was used to bring soft segments into the material structure. The total amount of bio-based starting materials was as high as 35%. Evidence for the reaction between the prepolymer and lignin was observed using Fourier transform infrared spectroscopic analysis and 13C nuclear magnetic resonance spectroscopy. The thermal properties of the materials were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The mechanical and viscoelastic properties of the materials were determined by dynamic mechanical analysis (DMA). The glass transition temperatures ( Tg) obtained from DSC and DMA showed a trend of increasing Tg with the increasing amount of lignin. A similar trend was observed with TGA for the increasing thermal stability up to 550oC with the increasing amount of lignin. The lignin-polyurethanes obtained were stiff materials showing high Young's modulus values. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39714. [ABSTRACT FROM AUTHOR]

Biologically derived polyesters known as polyhydroxyalkanoates (PHAs) represent a potentially "sustainable" replacement to fossil‐fuel‐based thermoplastics. However, current commercial practices that produce PHA with pure microbial cultures grown on renewable, but refined, feedstocks (i.e., glucose) under sterile conditions do not represent a sustainable commodity. Here, we report on PHA production with a mixed microbial consortium indigenous to an activated sludge process on carbon present in municipal wastewaters. Reactors operated under anaerobic/aerobic and aerobic‐only mode and fed primary solids fermenter liquor maintained a mixed microbial consortium capable of synthesizing PHA at 10 to 25% (w/w), while reducing soluble COD by approximately 62 to 71%. More critically, an aerobic batch reactor seeded from the anaerobic/aerobic reactor and fed fermenter liquor achieved approximately 53% PHA (w/w). Results presented suggest that environmentally benign production of biodegradable polymers is feasible. We further used PHA‐rich biomass to produce a natural fiber‐reinforced thermoplastic composite that can be used to offset advanced wastewater treatment costs. [ABSTRACT FROM AUTHOR]

Complete structures, including the location of N-acetylneuraminic acid (Neu5Ac) residues, were assigned for the core regions of Campylobacter jejuni serotypes O:1, O:4, and O:23 and O:36 lipopolysaccharides (LPS). In continuation of earlier studies, structure determinations of liberated oligosaccharides and, where necessary, of intact LPS, were by [sup1]H-NMR spectroscopy, Smith degradation, chromium trioxide and enzymic degradations, in conjunction with methylation studies supported by fast-atom-bombardment mass spectrometry and linkage analyses by gas chromatography/mass spectrometry. It was concluded on the basis of the following structures, in which each was linked 1→5 to a terminal 3-deoxy-D-manno-octulosonic acid residue, that the core regions with qualitatively similar sugar compositions showed serotypic differences in one or more of their sequences, linkage types, and anomeric configurations: (formula???).The outer regions of each structure carry Neu5Ac residues linked 2→3 to available β-D-Galp residues and show striking similarities with various glycosphingolipids of the ganglioside family. However, Neu5Ac epitopes are not apparently involved in determining serospecificity. [ABSTRACT FROM AUTHOR]

Over 9 million dairy cows generate an estimated 226 billion kg of wet manure annually in the USA. To help mitigate dairy greenhouse gas ( GHG) emissions associated with the degradation of this organic-rich waste, manure can be processed via anaerobic digestion ( AD) to methane and ultimately electricity. This potential value of AD has generated high-level dairy-industry support for broad-scale technology deployment; however, on-the-ground AD realization has been impeded by process stability/reliability concerns and poor economics. Considering these challenges but recognizing that AD represents a fundamentally sound manure-management approach, an interdisciplinary research team has completed proof-of-concept investigations on an integrated process that will concurrently improve manure management economics and reduce dairy GHG emissions. The integrated processes center on a two-stage fermentation/ AD system that can generate methane quantity/quality comparable to conventional single-stage AD. Molecular level investigations confirm that the AD is highly enriched with a unique and synergistic microbial population which yielded a more resilient and stable process. Beyond AD, algae grown on nitrogen/phosphorus-rich AD supernatant in a photobioreactor yielded biomass concentrations approaching 1.0 g L-1; despite an apparent growth lag/inhibition associated with excess organic acids and ammonia, algae growth was significant. Environmental life cycle assessment ( LCA) demonstrated that the two-stage AD configuration coupled with algae production can reduce GHG emissions by approximately 60% as compared with a traditional anaerobic lagoon. The end result is a manure-management platform that can increase US dairy viability and sustainability. Ongoing investigations are aimed at process refinement with an ultimate commercialization goal. © 2013 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]