Abstract Polymeric composite materials, presenting a practical solution for sealing non-metallic expansion joints under extreme conditions such as high temperatures and harsh chemical and physical abrasion, were investigated in this scientific study to discern the impact of welding parameters on their degradation and properties. The study entailed the bonding of polymeric composite blankets through hot plate pressing with a PTFE film, encompassing variations in temperature, duration, and load application. The findings elucidated that lower temperatures and shorter processing times failed to achieve optimal blanket adhesion, while higher temperatures led to material degradation, subsequently diminishing the mechanical strength of the welded joint. In contrast, extended processing times and the application of load during welding demonstrated a positive correlation, enhancing the mechanical strength of the joint by ameliorating interfacial adhesion. This research underscores the critical significance of carefully selecting welding parameters to ensure the peak performance and durability of polymeric composite structures. materials nonmetallic non metallic abrasion properties film temperature duration adhesion contrast correlation structures

Abstract This work consisted of studying polyglycerols in an acidic and micellar environment. The effects on surface tension, micellisation, and the Gibbs free energy of interface liquid-liquid (w/o) for directing the etherification of monomer glycerol with n-hexanol, n-octanol, n-decanol, n-dodecanol, and micellar solutions of sodium dodecylsulfate and dodecylbenzenesulfonic acid were studied at 70, 90 and 130°C . Polyglycerols with low weights and prepolymers were obtained. Theoretical methods such as density functional theory and molecular dynamics simulations were used to examine the effects of surface tension, the conformations of glycerol, and the position of the hydroxyl group of alcohols. A theoretical analysis (DFT/B3LYP) of the potential energy surface of glycerol and alcohols allowed finding stable conformations of the molecule, differing in the relative arrangement of hydroxyl groups. Our results helped achieve a better understanding of the interaction complex process of surfactant/catalyst of glycerol reactions in biphasic systems. environment tension micellisation liquidliquid liquid w/o wo w o (w/o nhexanol, nhexanol n hexanol, hexanol n-hexanol noctanol, noctanol octanol, octanol n-octanol ndecanol, ndecanol decanol, decanol n-decanol ndodecanol, ndodecanol dodecanol, dodecanol n-dodecanol 70 9 130C C 130 obtained DFT/B3LYP DFTB3LYP DFTBLYP DFT B3LYP B LYP (DFT/B3LYP molecule groups surfactantcatalyst surfactant catalyst systems 7 13 DFTB BLYP 1

Abstract Plasticulture improves crop quality and yield through polymeric films, but their improper disposal harms the environment due to humidity and contamination. This study aimed to develop biodegradable mulch films using soybean and peanut hulls and poly (butylene-adipate-co-terephthalate) (PBAT). The residues were characterized by thermogravimetric analysis and mulch films were evaluated by water absorption, contact angle and mechanical properties. The thermal behavior of the residues indicated stability below 200ºC. The agro-waste improved hydrophobicity but increased the water absorption values of the films by up to 18.5x (PBAT/SH5 after 14 days). Micrographs obtained by scanning electron microscopy indicated an important distribution of residue particles and formation of agglomerates, leading to lower mechanical performance. The study found that agro-industrial residues in powder form can be added to the polymeric matrix to produce biodegradable mulch films through traditional processing techniques. This approach has the potential to contribute to a more sustainable production system. contamination butyleneadipatecoterephthalate butylene adipate co terephthalate (butylene-adipate-co-terephthalate PBAT. PBAT . (PBAT) properties 200ºC ºC agrowaste agro waste 185x x 18 5x PBAT/SH5 PBATSH5 PBATSH SH5 SH (PBAT/SH 1 days. days days) agglomerates performance agroindustrial industrial techniques system (PBAT PBAT/SH

Abstract Waterborne polyurethane (WPU) coatings used for moisture protection of surfaces have been used broadly. They have been considered environmentally friendly because their synthesis releases less or no volatile organic compounds (VOCs) to the atmosphere. With the Covid-19 pandemic concerns, cleaning protocols of these surfaces have been applied and scientific knowledge about the effects of these liquids on WPU surfaces is necessary. In this work, diffusion experiments were performed using four liquids, in pure WPU and WPU filled with graphene oxide (GO). Detergent had the most severe effect on polyurethane films, causing severe cracks and weight loss. Diffusion parameters of HCl 5% and HCl 10% were greater in WPU/GO nanocomposites than in pure WPU. Mechanical tests under chemical aging showed that alcohol reduced most the tensile strength and Young modulus. Overall, GO protected the films for all liquid exposures, increasing their tensile strength and Young modulus. (WPU broadly VOCs (VOCs atmosphere Covid19 Covid 19 Covid-1 concerns necessary work GO. . (GO) loss 5 10 WPUGO modulus Overall exposures Covid1 1 Covid- (GO

Abstract Scaffolds with osteoconductivity, biocompatibility and good mechanical properties are promising for local drug release of sodium alendronate (ALN), a first-choice drug for treatment of bone tissue diseases, with low bioavailability. The viability to manufacture poly (L-lactic acid) (PLLA)/poly (methyl methacrylate) (PMMA) filaments containing ALN in different proportions, through extrusion, followed by scaffolds using 3D printing by fusion deposition modelling (FDM) and to investigate the influence of processes in mixtures drove this study. Differential scanning calorimetry (DSC), spectroscopy in the infrared region with Fourier transform (FTIR/ATR), and X-ray diffractometry (XRD) analysis indicated that PMMA decelerates crystallinity and confers malleability to PLLA/ALN mixture, besides its good processability and miscibility with PLLA and no relevant changes in physicochemical properties of components. Field emission scanning electron microscopy (SEM/FEG) showed good interfacial compatibility between PLLA/PMMA and homogeneously dispersed drug crystals in matrix. PLLA-PMMA-ALN scaffolds were manufactured by accurate with interesting properties for bone tissue engineering. osteoconductivity ALN, , (ALN) firstchoice first choice diseases bioavailability Llactic L lactic acid PLLA/poly PLLApoly /poly methyl methacrylate (PMMA proportions extrusion D FDM (FDM study DSC, DSC (DSC) FTIR/ATR, FTIRATR FTIR/ATR FTIR ATR (FTIR/ATR) Xray X ray XRD (XRD PLLAALN mixture components SEM/FEG SEMFEG SEM FEG (SEM/FEG PLLAPMMA matrix PLLAPMMAALN engineering (ALN (DSC (FTIR/ATR

Abstract The inlet velocity of thermoplastic in injection molds plays a crucial role in obtaining high-quality polymer parts and the final performance of the product. It is known that the way the polymer is injected into the mold can directly affect important properties, such as the distribution of internal stresses, the cooling rate and the formation of surface defects. However, there are injection molding machines that only control injection pressure and dosage, making it difficult to obtain the gate inlet velocity into the mold cavity. Besides, some molds have many injection channels as well as complex inlet geometries, which make a challenging task to identify the inlet velocity. This study presents numerical and experimental approaches on how to determine the entry velocity in thermoplastic injection molds. The main results showed that these methods are highly efficient and contribute to identifying the gate inlet velocity with good accuracy. highquality high quality product properties stresses defects However dosage cavity Besides geometries accuracy

Abstract This study examines the effect of processing parameters and reactive extrusion on the mechanical, thermal, morphological, and rheological properties of low-density polyethylene (LDPE) and sepiolite composites (LDPE/sepiolite: 95/5 wt/wt) produced by in situ reactive extrusion in a twin-screw extruder. Using a design of experiments, the contribution of the factors reverse mixing elements (RE), maleic anhydride (MA), and dicumyl peroxide (DCP) was determined. The results showed that a better interaction between LDPE and sepiolite phases occurred when reactive extrusion was carried out, leading to a satisfactory balance between mechanical properties and thermal stability behavior. The rheology analysis revealed that a more pronounced solid-like behavior was achieved in the composite prepared by reactive extrusion and in the presence of the filler. The SEM micrographs showed the appearance of a network-like morphology in the composite processed in the presence of additives and sepiolite filler. morphological lowdensity low density (LDPE LDPE/sepiolite LDPEsepiolite (LDPE/sepiolite 955 95 5 95/ wt/wt wtwt wt twinscrew twin screw extruder experiments RE, RE , (RE) MA, MA (MA) DCP (DCP determined out solidlike solid like filler networklike network 9 (RE (MA

Abstract This paper investigates evidence regarding the influence of a CaSt2 residual additive in the optical properties of a commercial polystyrene. This work proposes an in-line optical detector operating by illuminating the polymer with a red monochromatic light in order to evaluate its thermal behavior during a heat cycling. The detection system was bench validated by measuring the light absorption of aqueous solutions of organic acid dyes. The system showed great sensitivity in detecting the contamination’s effect on the polymer, as a great impact on the polymer’s behavior was observed due to the presence of the additive during different thermal cycles. The detector system showed that the salt’s presence elevates absorbance by five times when the temperature is higher than its fusion temperature. The in-line optical detector has proved to be suitable to quantify the presence of additives that affects the polymer’s optical properties. CaSt polystyrene inline line cycling dyes contaminations contamination s polymers cycles salts salt

Abstract The objective of this study was to characterize the physicochemical-mechanical properties of corn and cassava starch films reinforced with CNF via Tape-Casting. There were differences in size and shape of the starch granules. Corn starch nanocomposites (NCO) showed a significant increase in tensile strength (5.14 to 25.58 MPa) and significant decrease in strain (24.81 to 2.76%) as the CNF concentration increased. Among the cassava starch nanocomposites (NCA), only the cassava starch sample with 1% CNF (NCA-1) showed significant difference both in the maximum stress (4.94 MPa) and strain (15.17%). The corn starch sample with 2% of CNF (NCO-2) presented a lower roughness and NCA-1 a smooth surface. There was no difference in chemical composition between the samples. The CNF-free starch films showed more transparency than other films. The NCA showed more transparency than NCO. Tape-casting technique unveils enhanced mechanical properties of cellulose nanofiber-reinforced starch films. Starch nanocomposites exhibit improved tensile strength and surface characteristics. physicochemicalmechanical physicochemical TapeCasting. TapeCasting Tape Casting. Casting Tape-Casting granules NCO (NCO 5.14 514 5 14 (5.1 2558 25 58 25.5 MPa 24.81 2481 24 81 (24.8 2.76% 276 2 76 increased NCA, , (NCA) 1 NCA1 (NCA-1 4.94 494 4 94 (4.9 15.17%. 1517 15.17% . 15 17 (15.17%) NCO2 (NCO-2 NCA- samples CNFfree free Tapecasting casting nanofiberreinforced nanofiber characteristics 5.1 51 (5. 255 25. 24.8 248 8 (24. 2.76 27 7 (NCA (NCA- 4.9 49 9 (4. 151 15.17 (15.17% (NCO- 5. (5 24. (24 2.7 4. (4 15.1 (15.17 ( (2 2. 15. (15.1 (15. (15 (1

Abstract In this study, thyme essential oil was added to poly (butylene adipate-co-terephthalate) (PBAT) films in a variety of compositions (0, 1, 2, 5, 10, 15, and 20% w/w), and the effect of the essential oil on the PBAT's characteristics was evaluated. The films were produced using the casting technique. Thyme essential oil (EO) was evaluated by mid-infrared, gas chromatography-mass spectrometer, and antimicrobial activity. The films were evaluated by mid-infrared, mechanical, and thermal tests. The results demonstrated that EO has a higher concentration of o-cymene and antimicrobial activity against the bacteria Escherichia coli and Staphylococcus aureus. The films were analyzed for their mechanical and thermal properties according to the compositions tested. The films have shown promise for use as active packaging. study butylene adipatecoterephthalate adipate co terephthalate adipate-co-terephthalate PBAT (PBAT 0, 0 (0 1 2 5 10 15 20 w/w, ww w/w , w w/w) PBATs s technique (EO midinfrared, midinfrared mid infrared, infrared mid-infrared chromatographymass chromatography mass spectrometer tests ocymene o cymene aureus tested packaging (

Abstract This paper investigates the electrical, morphological, and mechanical behavior of ultrathin layer-by-layer polyaniline/poly(vinyl sulfonic acid) (PANI/PVS) ultrathin films for ammonia gas sensing. Atomic force microscopy shows that the PANI/PVS surface's roughness increases almost linearly with the number of PANI/PVS bilayers, while the surface morphology varies from a rod-like structure to a film-like architecture. Impedance measurements and their representation by a Cole-Cole model confirm this transition at ~15 bilayers. The designed sensor shows low response time (< 1 min), an optimal operating frequency range (1–100 Hz), high stability and sensibility to ammonia (~ 98 kΩ/ppm), and low sensibility to strain (~ 3.6 kΩ/%). This study suggests that hopping carriers' concentration remains constant, and hopping carriers' mobility changes with the number of bilayers. The simultaneous analysis of morphology with complex impedance measurements is a strategy for enhancing the electrical performance of low-cost and flexible organic sensing devices. morphological layerbylayer layer polyaniline/polyvinyl polyanilinepolyvinyl polyaniline/poly vinyl polyaniline poly acid PANIPVS PANI PVS (PANI/PVS surfaces s bilayers rodlike rod like filmlike film architecture ColeCole Cole 15 ~1 < ( min, min , min) 1–100 1100 100 (1–10 Hz, Hz Hz) ~ 9 kΩ/ppm, kΩppm kΩ/ppm kΩ ppm kΩ/ppm) 36 3 6 3. kΩ/%. kΩ/% . kΩ/%) carriers constant lowcost cost devices polyvinyl polyanilinepoly 1–10 110 10 (1–1 kΩ/ 1–1 11 (1– 1– (1

Abstract Bio-high density polyethylene (BHDPE) films with organoclay and antimicrobial additives (zinc pyrithione) were evaluated. The composites were prepared in a single-screw extruder using the melt intercalation technique, and the films were obtained by flat extrusion. The diffractograms indicated the formation of an intercalated nanocomposite (BHDPE/6 wt% of clay). Infrared spectra suggested that the polymer predominates over the antimicrobial agent bands. Thermal stability was slightly reduced by up to 3°C. The clay and antimicrobial agent reduced the melting point and crystallinity of BHDPE by up to 12 °C and 13.3%, respectively. In addition, the presence of clay and antimicrobial agent significantly (p < 0.05) affected all mechanical properties. Proliferation of Staphylococcus aureus demonstrated that both evaluated additives did not significantly (p > 0.05) inhibit microbial growth. The results emphasize a promising application of the films for packaging that does not require antimicrobial control, with films highlighted by 6 wt% of clay. Biohigh Bio high (BHDPE zinc pyrithione singlescrew single screw technique extrusion BHDPE/6 BHDPE6 (BHDPE/ wt . clay) bands 3C C 3 3°C 1 133 13 13.3% respectively addition p 0.05 005 0 05 properties growth control BHDPE/ 13.3 0.0 00 13. 0.

Abstract One of the most widespread applications of poly(lactic acid) (PLA) is as a raw material in the form of filaments for 3D printing. To improve final disposal alternatives and minimize their effects on the environment, the aim of this study is to determine the biodegradability of 3D-printed PLA waste composted in a landfill with leachate soil and garden soil for 90 days and 180 days. The soil characteristics and material properties were evaluated by laboratory analyses. Changes in soil chemical composition and the loss of microorganisms were recorded. The thermal and mechanical properties of PLA did not change significantly, but fungal colonies, encrustation, and changes in the original colour were found, indicating the onset of surface biodegradation of the samples. Controlled conditions or longer periods would be needed to maintain an ecosystem favourable to biodegradation; otherwise, PLA could accumulate in the environment, causing future pollution problems. polylactic poly lactic acid (PLA D printing environment 3Dprinted Dprinted printed 9 18 analyses recorded significantly colonies encrustation found samples otherwise problems 1

Abstract Fossil-origin plastics have raised great concerns due to their non-biodegradable nature. Biodegradable polymers can be an alternative for these materials’, however they have higher cost. The use of agro-industrial waste in blends with biopolymers can provide cheaper materials’ with improved properties. This study aims to develop low-cost biodegradable materials by extrusion and thermoplastic injection using oat hulls, polybutylene succinate (PBS), and starch. Six formulations with different concentrations of oat hulls (0-56% w/w) were extruded in a single-screw extruder, and then the materials were produced by thermoplastic injection. The extrusion aligned the oat hull fibers, making the material dimensionally stable. The oat hulls enhanced stiffness and reduced material density compared to non-hull counterparts. Besides that, the oat hulls are a low-cost agro-industrial byproduct, and it was possible to produce biodegradable materials with up to 56% hulls and only 20% PBS. These biodegradable materials are environmentally friendly and non-toxic. Fossilorigin Fossil origin nonbiodegradable non nature materials, , cost agroindustrial agro industrial properties lowcost low PBS, PBS (PBS) starch 056% 056 0 56 (0-56 w/w ww w singlescrew single screw extruder fibers stable nonhull counterparts that byproduct 20 nontoxic. nontoxic toxic. toxic non-toxic (PBS 05 5 (0-5 2 (0- (0 (

Abstract This article details the development of hybrid composites with a PLA matrix filled with coffee husks, potassium feldspar, and Bahia Beige marble. Comprehensive analysis included FTIR, hardness, contact angle, density tests, SEM for microstructural insights, and XRF for optimizing raw material compositions. Also, variance analysis was applied in all results. The study revealed that these biodegradable composites hold promise for sustainable applications. Density variations were noted due to particle compaction, and hardness slightly decreased with coffee husks, attributed to uneven component distribution. Increased hydrophilicity was observed with filler addition. SEM confirmed strong interfacial adhesion, and color consistency was maintained. Notably, coffee husks significantly enhanced the degradation rate of PLA, achieving a 100% higher rate compared to pure PLA. The presence of calcium and potassium minerals offers additional benefits for soil health. The study suggests that thermoformed, multi-layered composite capsules can be fully biodegradable, promoting environmental sustainability in coffee capsule production. feldspar marble FTIR angle tests insights compositions Also results applications compaction distribution addition adhesion maintained Notably 100 health thermoformed multilayered multi layered production 10 1