Polymer composites were prepared by in situ incorporation of sodium montmorillonite (NaMMT) and TiO2 into a growing terpolymer during polymerization of acrylonitrile (AN), N-vinyl-2-pyrrolidone (VP), and acrylic acid (AA). Several composites were formulated by altering the AN: VP: AA molar ratios and weight percentages of NaMMT and TiO2 fillers. Ultrafiltration (UF) membranes were prepared from these composites by phase inversion of their dimethyl acetamide (DMAc) solutions in water. The composite membranes were characterized and used for removal of a cationic dye, methylene blue (MB), from water in the presence of a polyelectrolyte sodium polyacrylate (NaPA) using polymer enhanced UF (PEUF). The effect of copolymer compositions, wt.% of clay and TiO2, and the concentration of the NaPA on flux and dye rejection were studied. The unfilled M20 copolymer membrane containing 20 M% of VP+AA and the same filled membrane containing 1 wt.% clay and 1 wt.% TiO2 exhibited a flux (L & centerdot;m(-2)& centerdot;h(-1))/rejection (%) of 135.67/93.7 and 146.7/95, respectively, from a feed of 0.15 mmol & centerdot;L-1 MB in the presence of 0.3 mmol & centerdot;L-1 NaPA, at a transmembrane pressure of 0.2 MPa. The filled membrane showed 94% degradation of 0.15 mmol & centerdot;L-1 MB for 100 min exposure to sunlight with a first order rate constant of 0.0054 min(-1).

Sodium alginate (SA) was grafted to poly (acrylonitrile-co-sodium acrylate-co-acrylic acid). The grafted copolymer was crosslinked with N. N, methylene bis acrylamide (MBA). Silver nanoparticles (AgNPs) were generated in situ within the growing polymer network by reducing 0.1 mM silver nitrate with 0.05 mM ascorbic acid (ASA). The effect of initiator concentration, total monomer concentration, SA weight%, MBA weight% and acrylonitrile (AN):sodium acrylate (NaAA)/ acrylic acid (AA) molar ratios on the grafting were studied. The nanocomposite was characterized and used for adsorption of methylene blue (MB) dye from water. The composite was also used for photocatalytic degradation of the dye in the presence of sun light. The Box-Behnken design (BBD) of response surface methodology (RSM) with different compositions resulted in an optimized composition of 5:1 M ratio of AN:NaAA/AA, 1 wt% MBA and 2 wt% SA. The nanocomposite (SACP5Ag) prepared with the optimized composition showed an equilibrium batch adsorption(q(e), mg/g)/removal(R)% of 245/98 from 50 mg/L MB dye in water and a q(e) /R% of 18.87/31.4 in a fixed bed adsorption at a feed inlet concentration(mgL(-1))/inflow rate (mLmin(-1))/bed height (mm) of 100/20/25. The composite showed a photocatalytic degradation efficiency of 98 % in sunlight for 80 min and a 1st order rate constant of 0.02 min(-1).

Photocatalytic membranes can simultaneously remove and degrade organic pollutants in water. Nano TiO2 and sodium montmorillonite (NaMMT) nanoclay were incorporated into poly (acrylonitrile-co-N-vinyl-2-pyrrolidone) copolymers during their synthesis via emulsion polymerization. A number of photocatalytic nanocomposites were prepared by altering the molar ratios of acrylonitrile and N-vinyl-2-pyrrolidone and the weight % of TiO2 and clay. These nanocomposites were converted into ultrafiltration membranes by the phase inversion technique. The membrane polymers were characterized. The contact angles, mechanical characteristics, molecular weight cut-off (MWCO), antifouling characteristics, and pore size distribution were used to analyze the resulting membranes. The membranes were utilized for the removal of cationic methylene blue dye from water in the presence of anionic sodium dodecylsulfonate (SDS) emulsifier by micellar-enhanced ultrafiltration (MEUF). The membrane fabricated with acrylonitrile:N-vinyl-2-pyrrolidone molar ratio of 10:1, 1% TiO2, 1% NaMMT, and an evaporation time/gelation temperature of 90 s/30 degrees C showed a flux/rejection of 88.1 L/m2h/98% for 50 mg/L methylene blue in the presence of 10 mM SDS at an operating pressure of 0.1 MPa. The same membrane showed 95.5% degradation after 150 min exposure to sunlight with a first-order rate constant of 0.0046 min-1.

ABSTRACTPolyvinyl alcohol (PVA), sodium polyacrylate, and polyacrylonitrile are very effective for stabilizing and controlling the size of nanoparticles. Thus, PVA was grafted to the copolymer of acrylonitrile (AN) and acrylic acid/sodium acrylate (AA/NaAA) using N,N′‐methylenebisacrylamide comonomer–crosslinker (MBA). Silver nanoparticles (AgNPs) were synthesized in situ in the polymerization mixtures by reduction of AgNO3 with ascorbic acid. These nanocomposites were characterized and used for the removal and photocatalytic degradation of p‐nitrophenol (PNP) from water. Based on the Box–Behnken design of the response surface methodology, the nanocomposite prepared with the AN:NaAA/AA molar ratio/MBA wt.%/PVA wt.% of 5:1/0.5/2 and impregnated with AgNPs of 18–30 nm average size (noted as PVACP5Ag) showed the optimized results. PVACP5Ag showed the equilibrium batch adsorption (qe, mg/g) of 240.93 from 50 mg/L PNP in water and a qe of 36.2 in fixed bed adsorption at a feed inlet concentration (mgL−1)/inflow rate (mLmin−1)/bed height (mm) of 50/30/30. The same composite showed a degradation of 96% after 7 min of exposure to sunlight in the presence of NaBH4 with a first‐order rate constant of 0.3 min−1 and 90.3% degradation after 110 min of exposure with a first‐order rate constant of 0.01 min−1 without any reducing agent.

Methyl methacrylate (MMA) and methacrylic acid (MA) at different MMA: MA molar ratios were synthesized and crosslinked with N, N'-methylenebisacrylamide (MBA) by emulsion polymerization in the presence of carboxymethyl cellulose (CMC). Copper nanoparticles (Cu-NPs) were synthesized by the reduction of CuSO4 with ascorbic acid in situ in the growing polymer network. The CMC- grafted, Cu-NPs- filled, and MBA-crosslinked nanocomposites were characterized and the MMA: MA molar ratios, wt% of MBA crosslinker, and wt% of CMC, were optimized for batch adsorption of 50 mg/L of tetracycline from water using the Box-Behnken design (BBD) of response surface methodology (RSM). The nanocomposite prepared with an MMA: MA molar ratio of 5:1, 1 wt% MBA, and 1 wt% CMC (noted as C5G1Cu) exhibited a batch adsorption capacity, qe, of 242.46 mg/g and a removal percentage of 97 %. The same nanocomposite showed a qe of 24.2 mg/g and a removal percentage of 32 % for the column adsorption of 100 mg/L tetracycline at a flow rate of 20 mL/min and a bed height of 25 mm. The nanocomposite also exhibited a photochemical degradation of 87 % of tetracycline in visible light with a pseudo first-order rate constant of 0.02 min-1.

Cyanogenic glycosides are naturally occurring plant compounds that serve as chemical defences but pose significant health risks due to their potential to release hydrogen cyanide. Found in dietary staple foods such as cassava, bamboo shoots, and stone fruits, these compounds are particularly concerning in regions with high dependence on such foods. This review provides a detailed analysis of the toxicology of cyanogenic glycosides, focusing on their metabolism, the mechanisms underlying their toxicity, and their broader implications for human health and environmental safety. Traditional detection methods for cyanogenic glycosides and recent advancements in innovative sensing technologies are discussed. Special emphasis is placed on biosensor-based approaches, including electrochemical, optical, and fluorescence-based systems, which have demonstrated exceptional sensitivity, specificity, and rapid response times. These modern techniques are emerging as critical tools for ensuring food safety, particularly in high-risk regions. Integrating biosensors with digital technologies and data analytics is explored as a pathway to develop comprehensive, real-time monitoring systems for cyanogenic glycosides. The review also highlights regulatory frameworks' role in standardizing detection methodologies and ensuring public health. Challenges such as scalability, cost-effectiveness, and regional adoption are discussed alongside recommendations for multidisciplinary research and international collaboration. The findings underscore the potential of biosensor-based technologies to transform food safety protocols, while future research is needed to overcome existing limitations and achieve widespread implementation. This comprehensive overview informs strategies for reducing cyanogenic glycoside-related risks and enhancing global food safety.

Styrene (St), 1,4 vinyl pyridine (4VP) monomers and divinyl benzene (DVB) monomer-cum-crosslinker at different molar ratios were subjected to emulsion polymerization in the presence of FeCl2, 6H2O/FeCl3 & sdot;4H2O followed by the treatment with an aqueous ammonia solution to produce several iron oxide nanoparticles (IONs) impregnated crosslinked copolymer composites. The resulting polymer metal nanocomposites (PMNCs) were characterized by FTIR, proton and 13C NMR, UV-visible spectroscopy, XRD, XPS, DLS, magnetic properties, SEM and TEM. The PMNCs were used for batch and column adsorption and photocatalytic degradation of p-nitrophenol (PNP) from water. The PMNC4 composite prepared with an styrene:4VP molar ratio of 5:1 (16.7 mol% 4VP), 4 wt.% DVB crosslinker and 0.025/0.05 molar ratios of Fe(II)/Fe(III) salts leads to an optimum batch equilibrium adsorption (qe, mg/g)/removal% of 496.36/99.3 PNP from aqueous PNP of concentration 100 mg/L. The same composite showed an equilibrium PNP adsorption (qe) of 114.2 mg/g polymer and a removal% of 26.8 for an inlet feed concentration (Ci, mg/L)/flow rate (Qt, mL/min)/bed height (h, mm) of 100/30/30 in a fixed bed. The PMNC4 polymer showed a photodegradation efficiency of 98% with a 1st order rate constant of 0.029 min-1 after 70 min of degradation of 100 mg/L PNP in solar light.HighlightsCopolymer network of styrene, 4 vinyl pyridine and DVB were synthesized.Iron oxide nanoparticles were introduced into the network in-situ during synthesis.The metal polymer nanocomposites (PMNCs) were characterized.Synthesis parameters were optimized with respect to batch adsorption of PNP.PMNCs showed excellent fixed bed adsorption and photocatalytic degradation of PNP. Synthesis and structure of the filled PMNC and column adsorption of PNP by the polymer.image

Removal of highly toxic chromium ions from water is of utmost necessity. The objective of the present work was to prepare a low-cost ultrafiltration (UF) membrane for removal of Cr (VI) from water. UF membranes were prepared by phase inversion from the copolymers of acrylonitrile (AN) and partially neutralized acrylic acid (AA)/sodium acrylate (NaAA). Three such copolymers, CP15, CP10, and CP5 were prepared by emulsion polymerization with feed AN: AA/ NaAA molar ratios of 15:1, 10:1 and 5:1, respectively. Silver nanoparticles (AgNP) were incorporated in-situ during the polymerization by chemical reduction of silver nitrate with ascorbic acid. CP5 and AgNP filled CP5AgNP UF membranes were prepared by varying the polymer concentration in dope solution (Cp), evaporation time (teva) and gelation temperatures (Tgel). Various characterizations confirmed the structure, morphology, presence of AgNP, flux decline and antifouling properties of the membranes. For polymer enhanced ultrafiltration (PEUF), CP5 and CP5AgNP membranes prepared with Cp/teva/Tgel of 13 wt%/90s/30 degrees C with a molecular weight cut off (MWCO) of 7.4 kDa and 5.7 kDa, respectively, showed a pressure normalized flux/rejection of 184.64Lm-2 h-1 bar-1/88.8% and 177.77Lm-2 h-1 bar-1/91%, respectively from a feed containing 100 mg/L of Cr (VI) in the presence of 0.5 wt% PVA.

Crystalline glass-ceramic fillers were prepared from calcium carbonate, silica, alumina, and calcium fluoride by heating and subsequent quenching in cold water. The fillers were incorporated into natural rubber (1,4-cis-polyisoprene) and the filled rubber composites were crosslinked with sulfur in the presence of different rubber additives. The unfilled and filled rubber composites were characterized. The transport properties of benzene, toluene, and p-xylene (BTX) through the rubber composites were studied in terms of sorption, diffusion, permeation, and mass transfer coefficients. The effect of the ceramic fillers on the mechanical, thermal and transport properties were studied. The sorption data at different temperatures were used for calculating activation energy of diffusion, permeation, free energy, and enthalpy of sorption. The BTX remained in the liquid state within the composite matrix as evident from negative Delta S. The diffusion coefficient (D) and mass transfer coefficient (kmtc) of BTX decreased with the increase in filler loading. Accordingly, for the transport of BTX the unfilled rubber showed a D (D x 107 cm2/s) and mass transfer coefficient (kmtc x 104 cm/s) of 5.67/3.97/2.96 and 7.71/7.08/7.04, respectively which decreased to 5.06/2.95/2.57 and 7.53/6.95/6.90, respectively for the composite containing 50 wt.% ceramic filler. Preparation, characterization and transport properties of ceramic filler loaded vulcanized NR composite.image

Background: In micellar-enhanced ultrafiltration (MEUF) the aggregates of small dye molecules with surfactant are retained on the membrane surface. Methods: Sodium montmorillonite (Na-MMT) nano clay particles were incorporated into the growing polymer matrix during the emulsion polymerization of acrylonitrile (AN) with acrylic acid/sodium acrylate (AA/NaAA) at varied comonomer ratios to prepare different nanocomposites. UF membranes were prepared from these composites by phase inversion at varied casting conditions. These casting variables were optimized with a BoxBehnken Design (BBD) of the response surface methodology (RSM) model for a MEUF of 50 mg/L of a cationic dye methylene blue (MB) in the presence of 10 mM of an anionic surfactant sodium dodecyl sulfate (SDS). The polymer and the UF membranes prepared with the optimized composition were also characterized and used for permeation flux and rejection% at varied process conditions. The parameters of resistance series model and micellar efficiency were estimated. Results: The membrane prepared with the AN:AA-NaAA molar ratio/clay weight%/evaporation time/gel temperature of 5:1/ 1 %/109 s/30 C-degrees and SDS concentration of 10 mM showed an optimized flux/rejection of 555.1 Lm(-2)h-1 h(-1) /95 % in a cross flow mode at a 3 bar operating pressure . The unfilled membrane with a similar composition showed a flux/rejection of 566.5 Lm(-2)h(-1) h(-1) /93 %.

NaMMT clay incorporated and maleic acid (MA) crosslinked polyvinyl alcohol (PVA)-chitisan (CS) interpenetrating network (IPN) type nanocomposite membranes were prepared for dehydration of acetone by pervaporation (PV). FTIR, XRD, SEM, UV spectroscopy, mechanical properties, contact angle measurement, and DTA-TGA were used to characterize these membranes. The effect of clay, CS, and MA on the flux and separation factor for water were statistically optimized by Box-Behnken design (BBD). Accordingly, the membrane prepared with 39.3 wt.% CS, 3 wt.% each of MA and NaMMT nanoclay showed a flux/separation factor of 0.176-0.733 kg/m(2)h/ 277-168 for the pervaporative dehydration of 99 wt.% acetone.

Vinylsulfonic acid (VSA), acrylamide (AM) and N, N methylene bis acrylamide(MBA) were copolymerized by radical polymerization in the presence of gum ghatti (GG) and treated water hyacianth (WH) in water. Several composite copolymers were prepared by varying the i) AM: VSA molar ratios ii) wt% of GG and iii) wt% of treated WH based on a Box-Behnken Design(BBD) of a response surface methodology (RSM) model with three input variables and the batch adsorption capacity (mg/g) of 100 mg/L Cd (II) from water as response. The composite polymer was characterized by Fourier transform Infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis(TGA), X-ray photo electron spectroscopy (XPS), compressive strength, pH reversibility, pH at point zero charge (pHPZC), Brunauer-Emmett-Teller (BET) surface area and scanning electron microscopy (SEM). The network parameters of the composites were determined. The copolymer composite prepared with AM: VSA of 5:1 containing 10 wt% GG and 4 wt% treated WH showed an optimum batch adsorption capacity of 399.15 mg/g Cd (II) from water containing 100 mg/L Cd (II). The same composite showed an adsorption capacity of 170.1 mg/g and a removal% of 31.5 at a feed concentration/feed flow rate/bed height of 150 mgL(-1)/30mLmin(-1)/30 mm in a fixed bed column.

Isopropyl alcohol (IPA) selective membranes were prepared from poly(methyl methacrylate-co-butyl acrylate) copolymers based on their relative solubility parameter values. Several such copolymers were synthesized by varying the methyl methacrylate (MMA) and butyl acrylate (BA) molar ratios. The membranes prepared from these copolymers were characterized and used for pervaporative recovery of IPA from water in a dead end-cross flow pervaporation(PV). The effect of MMA molar% of the membranes and the feed concentration of IPA on the total flux(J), permeability(P), separation factor(beta PV) and membrane selectivity (alpha) for IPA were also studied. The effect of concentration polarisation was eliminated at a feed flow rate of 80 mL/min. Accordingly, for 4 wt% IPA in feed the membrane prepared from the copolymer containing 92 M% MMA showed a thickness normalised flux of 56.7 mu mkgm-2h- 1 and beta PV of 62 for IPA in PV with a feed flow rate of 100 mL/min. The 4 wt% IPA in the feed was concentrated to 72.06% after PV.

Analysis of tribological parameters of polymers and polymer-based composites (PBCs), including nanocomposites, and their evaluation by several test methods are industrially very significant. Tribotesting is very important for the characterization of friction, lubrication, and wear. The mechanism of these parameters appears in many tribological applications. In fact, the ranking and selection of polymers, PBCs, and lubricants for prevailing equipment or new applications are based on this analysis and testing. Lubricant performance is also evaluated by different tribological tests. Tribological tests are necessary for an in-depth understanding of the tribological parameters, which enables proper designing, construction, and functioning of different tribological systems. These tests and analysis, including new testing methods for PBCs, are included in this chapter. In fact, PBCs consisting of polymers filled with natural fibers or nanoparticles are being increasingly explored in the aviation industry, construction, automotive parts, bearings, and many others, which demand new test analysis. Accordingly, several types of wear and sliding friction of materials subjected to different American Society for Testing and Materials-based test rigs simulating real-time condition are described in detail. Factors such as interface temperature and surface roughness affecting wear in dry and wet conditions have been explained. Types of lubrication regimes and fundamentals of rolling, sliding, and sliding contact test methods are also included in this chapter.

Partially neutralized acrylic acid (AA)/sodium acrylate (NaAA) and N, N & PRIME;-methylenebisacrylamide (MBA) were subjected to intercalative copolymerization in aqueous solution of polyvinyl alcohol (PVA) in the presence of sodium montmorillonite (NaMMT) nano clay to prepare filled semi-interpenetrating network (FSIPN) type composite polymer networks. Filled Full IPN (FFIPN) composites were prepared in a similar way by additional crosslinking of PVA with maleic acid (MA) crosslinker. The polymers were characterized with FTIR, NMR, XRD, TGA, SEM, EDAX, TEM, XPS, DLS, PZC, and pH reversibility test. The synthesis variables were optimized with respect to batch adsorption of 100 mg/L each of methyl violet (MV) and congo red (CR) dye as response using the central composite design (CCD) of response surface methodology (RSM). The FFIPN prepared from polyacrylic acid (PAA)/sodium polyacrylate containing PVA/Clay/MBA/MA of optimized composition of 4/1.5/0.75/4 (wt.% of AA/NaAA), respectively, showed an optimized adsorption (mg/g adsorbent) of 459.16/417.31 of MV/CR as single dye and 438.01/417.31 of MV/CR in 1:1 binary mixtures of 100 mg/L feed concentration. The FFIPN showed an adsorption (mg/g) of 41.54/37.61 and removal% of 88.5/80.12 at a feed flow rate, bed height, and feed inlet concentration of 20 mL/min, 20 mm, and 50 mg/L, respectively.

Polymer metal nano-composites (PMNC) were synthesized by integrating different weight percentage of chitosan (CS), N,N '-methylenebisacrylamide (MBA) crosslinked poly(acrylic acid-co-hydroxyethyl methacrylate) copolymer and Cu nanoparticles (CuNPs). CuNPs were generated in situ during polymerization by reducing CuSO4.5H(2)O with ascorbic acid. The presence of the CuNPs in the polymer network, functionality, crystallinity, morphology, size distribution of the CuNPs, elemental composition, thermal characteristics, network parameters, pH sensitivity, and strength of the composites was evaluated. The CuNP-loaded PMNC4 composite prepared with 10:1 acrylic acid : hydroxyethyl methacrylate molar ratio, 1 wt% each of initiator and MBA crosslinker and 4 wt% CS showed a photodegradation efficiency of 64% in 5 h for 50 mg/L methyl violet dye in water. The same polymer showed a rejection of 91.45% and a mass transfer coefficient of 4.14 x 10(-5) cm/s for continuous adsorption of 20 mg/L Pb(II) ion in water in a fixed bed of height 22 mm for an inflow rate of 30 ml/min.

Sodium montmorillonite (NaMMT) nanoclay particles were incorporated in-situ in the copolymer matrix of Poly (acrylonitrile-co-ethyl acrylate) during its synthesis from different molar% of acrylonitrile (AN) and ethyl acrylate (EA) monomers by emulsion polymerization. Similar polymerization was also carried out in the presence of iron salts to generate iron nanoparticles (FeNP) in situ in the membrane matrix. The membranes were characterized by FTIR, NMR, molecular weight (M v ), XRD, DTA-TGA, SEM, TEM, EDAX, contact angles for hydrophilicity and mechanical properties. The sorption and permeation of acetone-water binary mixtures through these membranes were analyzed in terms of solvent-solvent and solvent-membranes interaction and also by solvent coupling with Flory-Huggins, ENSIC and six-parameter solution diffusion model. The synthesis variables were optimized with the central composite design (CCD) of response surface methodology (RSM). The filled membranes showed high sorption and pervaporation selectivity for water for dehydration of acetone, while for similar filler loading FeNP-filled membranes showed higher flux and selectivity than NaMMT clay filled membrane. The membrane prepared with AN:EA molar ratio of 5:1 and filled with 2 wt% NaMMT clay showed a flux(kg/m 2 h)/selectivity of 0.903/125.2, which further increased to 0.937/140 for the same membrane filled with 5 wt% FeNP for 90 wt% feed acetone.

Several interpenetrating network (IPN) type hydrogels were made by free radical crosslink copolymerization of acrylic acid (AA) in an aqueous solution of guar gum (GG). N’N-methylene bis acrylamide (MBA) was used as a crosslinker. The hydrogels were prepared by varying the synthesis variables such as concentration of the initiator, crosslinker, AA monomer and GG polymer in water. These hydrogels were characterized by FTIR, 13CNMR, SEM, XRD DTA-TGA and mechanical properties. The effect of the synthesis variables, solution pH, and the salts present in water on the swelling, diffusion and the network parameters of the hydrogels were studied. The release kinetics of a model drug pyridoxine hydrochloride (vitamin B6) was studied with these semi-IPN type polymers. The release rate of pyridoxine from the polymer at a solution pH of 7.5 was faster than its release rate at a pH of 1.5 due to its shrinkage at this low pH. The IPN prepared with 1wt% initiator, 1wt% crosslinker, 25 wt.% AA in water and 4 wt.% GG showed a high entrapment efficiency of 94% and a sustained release rate of 95% for pyridoxine drug in 30 h. The drug release data showed a close fitting to the Korsmeyer–Peppas model.

Pectin grafted polyacrylic copolymer hydrogels were made by free radical crosslink copolymerization of acrylic acid (AA) and acrylamide (AM) in an aqueous solution of pectin. N ' N-methylene bis acrylamide (MBA) was used as a crosslinker. During the polymerization reaction the attapulgite (APG) filler was also incorporated in situ into the network of the copolymer gel. Several filled hydrogels were prepared by varying the amount of pectin and APG filler. These hydrogels were characterized by FTIR, 13C NMR, XRD, TGA, SEM, mechanical properties, DMA, swelling, diffusion characteristics and network parameters. The release kinetics of a model drug diltiazem hydrochloride (DT) was studied with these hydrogels. The wt% of pectin, APG and MBA was optimized with a central composite design (CCD) model of response surface methodology (RSM) with equilibrium swelling ratio (ESR), drug adsorption (mg/100 mg gel) and drug release% in 16 h as response. Accordingly, the hydrogel prepared with 5:1 AA:AM molar ratio, 25 wt% monomer concentration, 1% each of initiator and MBA concentration, 18 wt% pectin and 2 wt% APG showed an optimized ESR of 17.75, drug loading of 27.58 and a drug release % of 92.5 in 16 h at a solution pH of 7.4.