High Temperature Melting Process Research Articles

Enhancing mechanical and rheological properties of HDPE films through annealing for eco-friendly agricultural applications

Abstract A composite of high-density polyethylene/ultra-high molecular weight polyethylene (HDPE/UHMWPE) was synthesized via a high-temperature melting process. We specifically examined the effects of annealing on the morphological and rheological properties of the composite. Using scanning electron microscopy and advanced rotational rheometry, we determined that annealing notably alters the composite’s microstructure, with a reduction in pronounced features post-treatment. Rheologically, UHMWPE content significantly enhanced mechanical properties, particularly in storage modulus (G′), loss modulus (G″), and complex viscosity (|η*|), which aligned with scaling law principles. Our findings highlight a distinct improvement in mechanical properties post-annealing, underscoring the potential of UHMWPE in enhancing polymer composite performance. The scaling laws relating G′, G″, and |η*| with UHMWPE were identified as follows: (1) pre-c e: G′ ∼ c 0.2, g″ ∼ c 0.07, |η*| ～ c0.07 and (2) post-c e: G′ ∼ c 1.20, g″ ∼ c 0.6, |η*| ∼ c 0.64, with a forward shift in c e noted after annealing. The addition of UHMWPE significantly enhanced the system’s properties, particularly after annealing. This study offers crucial insights into optimizing HDPE plastic films for enhanced durability and sustainability, ideally suiting them for eco-friendly agricultural uses.

Accurate identification of glass crystallization helps in selecting high electronic conductivity materials

Though the current research on vanadium-based glass electrodes has made great progress, the conductivity theory of V-based glasses has not been obviously improved and crystals cannot be positioned precisely. The changes in the valence state of V3+, V4+ and V5+ are regulated by the strong reducing agent Fe2P to realize valence bond transformation of the amorphous electrode, explore the redox process of multi-electron reactions and further optimize the conductivity of electrode materials. VPFe2 and VPFe3 precipitate VO2 crystals and VPFe4 precipitates VO2 and V6O11 crystals. Electron back-scattered diffraction was used to accurately identify the distribution and specific positions of both types of crystals. V6O11 crystals exhibit a strong texture according to pole figure and inverse pole figure. XPS reveals that Fe2P and V2O5, undergo a redox reaction during the high-temperature melting process, where V5+ is reduced to V4+ and V3+ and V4+ renders a positive influence on conductivity. The addition of Fe2P increases the content of V4+ in the glass and VPFe3 glass contains the highest content of V4+, leading to the highest electronic conductivity. V2O5 transforms into VO2 crystals and VO2 transforms into V6O11 with the increase of Fe2P content. The type of nanocrystal precipitation in glass affects electronic conductivity.

Enhanced solar-thermal and electro-thermal storage performance of solid-solid composite phase change material

Phase change material (PCM) is a highly sought-after thermal storage medium, but cannot directly reserve solar energy and electricity. In this study, a pentaglycerine (PG)-based composite solid-solid phase change material (SSPCM) was developed with the ability to convert and store solar-thermal and electro-thermal energy. The composite was prepared using a high temperature melting process with graphite paper (GP) and carbon nano tube (CNT) as functional additives. The performance tests showed that the composite has a phase change temperature of 80.5 °C, latent heat of 145.6 J/g, supercooling degree of 7.9 °C and electrical conductivity of 15.3 S/m. This composite could undergo solid-solid phase change and store solar energy in the form of latent heat under simulated sunlight. The phase change process can also be driven by direct current, with a 10 V power supply increasing the temperature of the composite to 90 °C within 32 min. These properties make the developed SSPCM promising for energy storage applications.

Enhancement of near infrared luminescence properties of B2O3–BaF2–TeO2–Nd2O3 glasses doped with Bi3+ or Sb3+

B–Ba–Te–Nd borate glasses doped with different heavy metals Bi3+ or Sb3+ were successfully prepared by a high temperature melting process. The basic properties, NIR luminescence properties and decay lifetime of the glasses under Bi3+ or Sb3+ doping conditions were investigated. Interestingly, it was found that doping with heavy metals Bi3+ or Sb3+ was effective in improving the structure of the borate glass matrix, effectively enhancing the 1067 nm luminescence intensity of Nd3+ ions by a factor of 1.78 and 1.53, respectively. In addition, the mechanism of improved luminescence by heavy metal doping was discussed in conjunction with FT-IR, emission spectra and decay curves. This study provides a new way to enhance the luminescence performance of borate-based glasses.

Permeability of wood impregnated with polyethylene wax emulsion in vacuum

Polyethylene wax (PEW) has emerged as a commonly used material for maintaining the quality of wood. The emulsification of solid PEW before being injected into wood can effectively overcome the shortcomings of the high-temperature melting and injection process of solid PEW. The permeability of Eucalyptus (Eucalyptus saligna) and Mongolian Scotch pine (Pinus sylvestris var. Mongolica) to PEW emulsion in vacuum environment was investigated using impregnation tests, and steaming pretreatment and microwave irradiation pretreatment were applied. The small particle size and low viscosity of the PEW emulsion, whose median particle size was 0.256 μm and viscosity was 52.2 mPa s (at 60 r/s), facilitated its penetration into the wood capillary system. The weight percent gain (WPG) of Eucalyptus and Mongolian Scotch pine post impregnation in vacuum was positively correlated with both the vacuum-holding time and the impregnation temperature, but after 60 min of impregnation the WPG of both wood species decreased significantly. Both pretreatment methods could substantially improve the wood permeability and effectively promote the penetration of the PEW emulsion into the wood. The maximum WPG was achieved when Eucalyptus and Mongolian Scotch pine were respectively steamed for 80 min and 120 min. There was an increase of 0.24 times for the former and an increase of 0.53 times for the latter compared to unpretreated wood. Both species exhibited the highest WPG after water immersion for 60 min (with average moisture content close to their fibre saturation point) and microwave irradiation for 30 s, which was respectively 0.28 and 0.75 times higher than that of unpretreated wood. There was a significant variation in WPG between the two species with the same pretreatment method. The relatively lower density and better-developed capillary system of Mongolian Scotch pine allowed more efficient penetration of PEW emulsion. It is recommended that, considering the time cost and practical enhancement, microwave irradiation should be given priority to when pretreating wood.

Preparation of Reference Material for Component Analysis of High Silica Glass Fiber

A reference material used for the component analysis of high silica glass fiber is prepared by the high-temperature melting process, a technique that can ensure the homogeneity and stability of each component. With two methods based on different principles, the components in glass fiber are accurately characterized through the joint efforts of multiple laboratories. The results show that the reference material was accurately and reliably characterized and exhibited good homogeneity and stability, and that the expanded uncertainty of the standard values was 5%-10% (k=2). Therefore, the reference material can be used to evaluate component testing methods for high silica glass fiber and calibrate related analytical instruments so that the accuracy and reliability of component characterization are ensured.

THEINFLUENCE OF MODIFICATION WITH YTTRIUM ON THE STRUCTURE AND PROPERTIES OF CASTINGS OBTAINED FROM THE ЖС6У-ВІ ALLOY RETURN

Purpose. To study the effect of modification of nickel-yttrium ligature with additives on the structure and physical and mechanical properties of ЖС6У-ВІ alloy, smelted using its own technological return in the charge.
 Research methods. On the УППФ-3М installation with the base crucible, experimental melting of standart technological return of the ЖС6У-ВІ alloy was carried out using high-temperature melt processing.
 Experimental samples for mechanical tests and determination of stress-rupture strength were cast from the obtained ingots, cut into measured batch blanks and cleaned in a shot blasting drum, using the method of equiaxial crystallization in ceramic molds.
 When pouring one ceramic mold, the metal melt at a temperature of 1540 °C was modified with a nickel-yttrium ligature of the ІтН1 brand (grain size 2...5 mm) in the amount of 0.136 % of the mass of the charge in a crucible with a holding time of 1 min 15 s ... 1 min. The second block was poured without modification.
 Cooling of the poured blocks was carried out at the melting site at normal ambient temperature.
 The samples underwent heat treatment according to ОСТ 1 90126-85: heating to a temperature of 1210 ± 10 °C, holding for 4 hours, cooling in air.
 The balance of the chemical composition of the experimental alloys was evaluated by the computational and analytical method.
 The chemical composition of the alloy of experimental variants was determined. The microstructure and mechanical properties at room temperature were studied. Stress-rupture strength tests were performed at 975 °C under a load of 230 MPa.
 Results. Experimental melting of the charge was carried out, which consisted exclusively of our own technological return of the ЖС6У-ВІ alloy with the use of high-temperature processing of the melt and modification with a nickel-yttrium ligature.
 The chemical composition, microstructure of the experimental alloy, its mechanical properties at room temperature, and heat resistance indicators were studied.
 A method of determining the degree of balance of the chemical composition of modern superalloys based on the total content of groups of alloying elements is proposed.
 Scientific novelty. Calculations carried out in accordance with the proposed method of determining the degree of balance of the chemical composition of the alloy show that for the experimental variants, phase separations may form along the grain boundaries. Studies of the microstructure confirmed the separation of the γ-γ' eutectic phase in the form of a “white” border along the thickened grain boundaries in the metal of the ЖС6У-ВІ alloy sample.
 According to the calculations of the metal alloying system balance for experimental melts, not only the thickening of the grain boundaries and the separation of the γ-γ' eutectic phase, but also a decrease in mechanical properties and stress-rupture strength can be observed.
 The application of modification with nickel-yttrium ligature in the amount of 0.136 % in the remelting process with the use of high-temperature processing of the ЖС6У-ВІ alloy return melt allows to ensure the formation of grain boundaries without visible discharges (pollution).
 It was established that in the metal of the experimental melting with the application of modification with nickel-yttrium ligature, carbides have globular and lamellar morphology. There is no separation of the γ-γ' eutectic phase.
 The mechanical properties and stress-rupture strength of the metal of the experimental melts with the use of high-temperature processing of the melt of the conditioned return of the ЖС6У-ВІ alloy, both with and without modification by nickel-yttrium ligature, meet the requirements of OST 1 90126-85, but at the same time, they are lower than the properties of the alloy cast with charge refreshment.
 Practical value. A computational and analytical method of determining the degree of balance of the chemical composition of modern heat-resistant alloys based on the total content of certain groups of alloying elements is proposed.
 It was established that the modification of nickel-yttrium ligature with additives significantly improves the microstructure of castings obtained from the technological return of the ЖС6У-ВІ alloy and creates conditions for a general improvement in the quality of the material of the responsible castings.
 The conducted studies show that the use of 0.136 % nickel-yttrium ligature allows to clean grain boundaries, change the morphology of non-metallic inclusions and counteract the segregation of eutectic inclusions in nickel-based superalloys alloys.

High Thermoelectric Performance of Cu3SbSe4 Obtained by Synergistic Modulation of Power Factor and Thermal Conductivity

In this work, Cu3–yAgySb1–xGexSe4 (x = 0, 0.04, 0.06, 0.08, 0.10, 0.12; y = 0, 0.1, 0.2, 0.3, 0.4) is fabricated using a high-temperature melting process, and the thermoelectric properties are investigated in the temperature range of 300–700 K. As a result, a remarkable improvement in thermoelectric performance of Cu-based ternary thermoelectric materials is achieved here. Ge doping increases the carrier concentration leading to a decrease in electrical resistivity; Ag alloying can reduce thermal conductivity significantly and enhance the power factor. Consequently, a maximum figure of merit, 0.95, is obtained for Cu2.7Ag0.3Sb0.94Ge0.06Se4 and Cu2.6Ag0.4Sb0.94Ge0.06Se4 at 700 K, which is higher than most reported Cu3SbSe4-based systems.

Improved Multidomain Convolutional Neural Network for Intelligent Tracking of Marangoni Effect Process Sequence Images

Sequence image target tracking has two requirements of accuracy and speed. Aiming at the problem of slow speed of convolutional neural network (CNN) target tracking algorithm, an improved algorithm for sequence image target tracking is designed by using a fusion of Faster multidomain CNN (MDNet) and optical flow method. The target algorithm designed in this article is improved on the basis of MDNet. The optical flow method is used to obtain the primary selection box first, which can effectively deal with the challenges brought by scale change and in-plane rotation, and has good tracking speed and performance. The objective algorithm of this article is used to explore the Marangoni effect in the melting process of solid iron tailings in molten blast furnace slag. Because the main component of iron tailings is Silica, and the melting point of Silica is the highest, so taking Silica as the research object, an intelligent analysis of Marangoni effect in high-temperature melting process of Silica particles is realized. The results show that the target algorithm achieves the real-time standard (FPS > 24), the average distance precision (DP) is 97.3%, the average success rate (SR) is 98.02%, the average center location error (CLE) is 6.2684 <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">μ</i> m, and the average overlap precision (OP) coverage is 63.86%. The target algorithm has certain advantages in the following five evaluation indexes: DP, SR, CLE, OP, and frames per second.

Atomic Layer Deposition (ALD) of Ultra-Thin Diffusion Barriers on ZnSe Microparticles for Phase Stability in Chalcogenide Glasses for Mid-Infrared Optics

ZnSe embedded chalcogenide glass (ChG) composites are optically active in the mid-infrared (IR) and are ideal for niche applications in medical diagnosis, military missile heat-sensing, and chemical identification. The embedded ZnSe crystals play a critical role in providing lasing activity while the ChG - As2S3-xSex matrix, acts as a host that can be drawn into fiber and provides the necessary mid-IR transparency. However, during synthesis, the ZnSe particles are prone to dissolution in the As2S3-xSex matrix due to a high temperature (650 oC) melting and homogenization process. Here we demonstrate that a thin amorphous barrier layer of Al2O3 deposited using atomic layer deposition (ALD) on ZnSe microparticles 5-10 mm in average diameter is successful to prevent ZnSe dissolution in the As2S3-xSex matrix even after extended melting and homogenization at 650 oC for 8 hours. This talk will highlight some of the key process innovations required to overcome challenges of ALD on powdered components for functionalizing and enhancing performance of multiphasic glasses for optical applications.Amorphous aluminum oxide (Al2O3) was deposited using alternate pulses of trimethyl aluminum and H2O on 1 gm batch size ZnSe using a customized rotary barrel reactor inside a viscous-flow ALD furnace attached to a quadrupole mass spectrometer (QMS). The temperature of deposition was kept at 180 oC and the number of cycles were varied from 100 to 300 cycles. The ZnSe particles were sieved to an average size of 5-10 mm and a maximum size ≤ 20 mm. The coated particles were characterized by x-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The crystallinity of the ZnSe-As2S3-xSex glasses were evaluated using x-ray diffraction (XRD) and their composition stability spatially mapped across individual ZnSe particles embedded in As2S3-xSex matrix using Raman microspectroscopy.Whereas 100 ALD cycles provide partial protection to dissolution for the ZnSe in As2S3-xSex, a 300 cycle ALD Al2O3 on ZnSe particles is sufficient to provide phase and composition stability to the ZnSe embedded As2S3-xSex glass. Through our investigation, we exemplify the efficacy and potential of ALD of ZnSe powder in improving the stability of optical materials while still achieving optimal mid-IR lasing and transparency.

Nucleation, crystallization and biological activity of Na2O-CaO-P2O5-SiO2 bioactive glass

The 58S Na2O-CaO-SiO2-P2O5 bioactive glass was successfully prepared by a high-temperature melting process, and the nucleation and crystallization behavior and hydroxyapatite (HA) precipitation of the 58S bioactive glass were investigated in detail. Optimum nucleation and crystallization conditions allow the preparation of 58S bioactive glass-ceramics with spherical hydroxyapatite (HA) crystals at the nanoscale. Compared with 45S bioactive glass, the resultant 58S bioactive glass possesses higher HA precipitation ability after treated by artificial saliva, and the brushite and HA phases can precipitate simultaneously, exhibiting higher bioactivity. The as-prepared 58S bioactive glass and glass-ceramic are promisingly used as bioactive materials in the fields of biomedicine and biotechnology.

Enhancing stability and luminescence quantum yield of CsPbBr3 quantum dots by embedded in borosilicate glass

Halide perovskite quantum dots have attracted considerable research interest as excellent candidate for photonic and optoelectronic applications due to their unique optoelectronic properties. Stability is prerequisite and therefore is of critical importance. Here we demonstrate highly stable luminescent CsPbBr3 quantum dots (QDs) can be achieved in different glass matrices via the high temperature melting process and melt-quench method. The microstructure of CsPbBr3 QDs glass as well as their optical properties are systematically characterized by microscopic techniques and time-resolved spectroscopic techniques. We conclude the surface passivation is the key aspect for the high stability and high luminescence by embedding the quantum dots in the glass matrix. This study provides technical method to form highly stable luminescent solid devices and detailed physical understanding which is critical for the practical applications.

Structure and up-conversion luminescence of Yb[formula omitted]/Ho[formula omitted] co-doped fluoroborate glasses

Yb3+/Ho3+ dual-doped fluoroborate glasses were obtained by high temperature melting process. Ultraviolet–visible spectrophotometer, XRD, FT-IR and fluorescence spectrometer were used to characterize the glass structure, transmittance, up-conversion (UC) emission spectrum and fluorescence decay time. The structural groups in all glasses were [BO4], [BO3] and [PO4] units. Transmissivity of all glass samples exceeds 60%. In addition, the fluorescence intensity ratio (FIR) technique was used to investigate the variation of UC luminescence at 543 nm (Ho3+: 5F4/5S2→5I8) and 659 nm (Ho3+: 5F5→5I8) under pump wavelength of 980 nm between 453 K and 653 K. The absolute sensitivity of glass sample at 653 K was 5 × 10−2 K−1 and the relative sensitivity was 9 × 10−4 K−1. The results indicated that Yb3+/Ho3+ co-doped fluoroborate glass has potential applications for up-conversion luminescence and optical temperature measurement.

A Scalable Manufacturing Approach to Single Dose Vaccination against HPV.

Human papillomavirus (HPV) is a globally prevalent sexually-transmitted pathogen, responsible for most cases of cervical cancer. HPV vaccination rates remain suboptimal, partly due to the need for multiple doses, leading to a lack of compliance and incomplete protection. To address the drawbacks of current HPV vaccines, we used a scalable manufacturing process to prepare implantable polymer–protein blends for single-administration with sustained delivery. Peptide epitopes from HPV16 capsid protein L2 were conjugated to the virus-like particles derived from bacteriophage Qβ, to enhance their immunogenicity. The HPV-Qβ particles were then encapsulated into poly(lactic-co-glycolic acid) (PLGA) implants, using a benchtop melt-processing system. The implants facilitated the slow and sustained release of HPV-Qβ particles without the loss of nanoparticle integrity, during high temperature melt processing. Mice vaccinated with the implants generated IgG titers comparable to the traditional soluble injections and achieved protection in a pseudovirus neutralization assay. HPV-Qβ implants offer a new vaccination platform; because the melt-processing is so versatile, the technology offers the opportunity for massive upscale into any geometric form factor. Notably, microneedle patches would allow for self-administration in the absence of a healthcare professional, within the developing world. The Qβ technology is highly adaptable, allowing the production of vaccine candidates and their delivery devices for multiple strains or types of viruses.

High thermal stability Cu2O@OZrP micro-nano hybrids for melt-spun excellent antibacterial activity polyester fibers

Public safety incidents caused by bacterial infections have attracted widespread attention towards antibacterial textiles (fibers, fabrics, etc.). Nevertheless, it is still challenging to efficiently load inorganic nano-antibacterial materials in polymer fibers. In this work, zirconium phosphate (ZrP, layered micro-nano materials) was utilized as a micro-nano carrier. The octadecyl triphenyl phosphonium bromide (OTP) was intercalated between the ZrP sheets by the ion exchange method to improve the carrier-polymer compatibility and the antibacterial performance. Through in-situ chemical reduction, the ultra-small nano-sized cuprous oxide (Cu2O < 5 nm) was loaded on the outer surface of ZrP to realize the uniform and stable dispersion of the Cu2O on the carrier and improve the antibacterial performance. The ZrP nanosheets loaded with Cu2O and OTP (Cu2O@OZrP) had excellent antibacterial properties, and the antibacterial rate against E. coli, S. aureus and C. albicans was more than 99 %. The intercalation amount of OTP in Cu2O@OZrP can reach 16 %, and the thermal stability was excellent and a significant increase in the Zeta potential. Indeed, the decomposition temperature was greater than 350 °C, which was suitable for high-temperature melt processing of polymers. Consequently, we prepared PET/Cu2O@OZrP fibers using polyethylene glycol terephthalate (PET), which accounts for 70 % of the total chemical fibers, as the fiber matrix. PET/Cu2O@OZrP fibers exhibited excellent mechanical property and antibacterial performance when the content of Cu2O@OZrP was only 0.2 %. The antibacterial rate against five types of bacteria including super bacteria (MRSA, VRE) was more than 99 %.

Microstructure and property relationship between Al-4.5Cu alloy and Al-4.5Cu-Al2O3 composite developed by mechanical alloying

The present work aims to fabricate an alloy (Al-4.5Cu) and a composite (Al-4.5Cu-Al 2 O 3 ) with the help of the mechanical alloying method. As compared to the high-temperature melting and casting process, mechanical alloying is a solid-state synthesis process, which requires low temperature for the synthesis of alloy and composite through powder metallurgy route. A high energy planetary ball mill mechanically alloy the Al, Cu, and Al 2 O 3 powders for 10 h with 200 revolutions per minute to milled the alloy and composite powder mixture. Then the milled powder mixtures are compacted in a single punch die compaction machine and then sintered at 550 and 660 °C for 1hr. XRD analysis of the sintered alloy and composite predicts the formation of a new phase, i.e., CuAl 2 . A comparative study of density, hardness, and compressive strength values of the alloy with the composite depicts that the un-sintered and sintered composite have better properties (density, hardness, and compressive strength) due to the presence of Al 2 O 3 and CuAl 2 . With increasing the sintering temperature from 550 to 660 °C, the properties further enhanced for both the alloy and composite.

Visible and Near-Infrared emission properties of Yb3+/Pr3+ co-doped lanthanum aluminum silicate glass

Yb3+/Pr3+ co-doped lanthanum aluminum silicate glasses (Yb3+/Pr3+-SAL glass) are prepared by high temperature melting process. The optical properties of Yb3+/Pr3+ co-doped lanthanum aluminum silicate glasses are studied. The result shows that Yb3+/Pr3+ co-doped lanthanum aluminum silicate glasses have intense absorption range from 440 to 500nm. In addition, the intense emission band centered at 620nm and 607nm are observed with the excitation of 488nm in different doping concentration. These results demonstrate that Yb3+/Pr3+ co-doped lanthanum aluminum silicate glasses can be used as a potential material for visible laser and near-infrared broadband fiber amplifiers.

Dynamic Compensation Model of BF Slag Homogenization Thermal Based on Advanced Deep Learning Algorithm

In recent years, deep learning has been widely used in the field of image visualization, and has attracted the attention of researchers. The main component of iron tailings is SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , In the process of quenching and tempering slag from iron tailings, melted SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> particles will randomly walk in the crucible, therefore, how to intelligently identify and track targets (SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> particles) in sequence image to promote the low consumption and efficient production of high value-added slag cotton has become an urgent problem. Aims at the temperature requirements of slag cotton preparation process, using intelligent algorithm with deep learning and hierarchical clustering, in-depth analysis of the visual information of the high temperature melting process of SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> particles. Through centroid tracking and positioning technology, intelligent edge feature extraction technology and fitting method of experimental data through high temperature melting process of SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> particles quantitative characterization functions of visual characteristics of SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> particles melting process under high temperature environment were obtained in this article. Approximation of the melting process of iron tailings in high temperature environments and embed this function into the static mathematical model of process thermal compensation an accurate thermal dynamic intelligent compensation model for slag cotton preparation process is realized.

Sustainable thermoplastic elastomers with a transient network

Vegetable oils and their fatty acids are convenient sources for polymers due to their wide availability, ease of functionalization, and lack of toxicity; however, the long alkyl chains of the fatty acids have a large impact on the resulting polymer properties. Polymers with bulky constituents, such as the long alkyl side-chains of fatty acid-derived polymers, typically exhibit poor mechanical performance due to lack of entanglements. In this study, hydrogen bonding moieties were incorporated into the fatty acid-based midblock of a thermoplastic elastomeric triblock copolymer as a means to improve its mechanical behavior. Poly(styrene-b-(lauryl acrylate-co-acrylamide)-b-styrene), containing lauryl acrylate (a derivative of lauric acid) and the hydrogen bonding comonomer acrylamide in the midblock, was synthesized via reversible addition-fragmentation chain transfer polymerization. The chemical and physical properties of triblock copolymers of varying composition were explored. Quantitative FTIR analysis confirmed the formation of a transient network, which exhibited a reduction in crosslink density with increasing temperature, beneficial for high temperature melt processing. The triblock copolymers exhibited spherical morphologies lacking long-range order at room temperature, which were unaffected by the presence of acrylamide. Moreover, the order-disorder transition temperature reduced with increasing acrylamide content, due to a reduction in the Flory-Huggins interaction parameter. Importantly, incorporation of acrylamide into the midblock greatly improved both the tensile strength and strain at break. Incorporation of a transient network into the midblock is therefore an effective method of improving the mechanical properties of triblock copolymer-based thermoplastic elastomers containing bulky constituents.

Lead recovery from waste CRT funnel glass by high-temperature melting process

In this research, a novel and effective process for waste CRT funnel glass treatment was developed. The key to this process is removal of lead from the CRT funnel glass by high-temperature melting process. Sodium carbonate powder was used as a fusion agent, sodium sulfide serves as a catalytic agent and carbon powder acts as reducing agent. Experimental results showed that lead recovery rate increased with an increase in the amount of added sodium carbonate, sodium sulfide, carbonate, temperature and holding time initially, and then reached a stable value. The maximum lead recovery rate was approximately 94%, when the optimum adding amount of sodium carbonate, sodium sulfide, carbonate, temperature and holding time were 25%, 8%, 3.6%, 1200°C and 120min, respectively. In the high-temperature melting process, lead silicate in the funnel glass was firstly reduced, and then removed. The glass slag can be made into sodium and potassium silicate by hydrolysis process. This study proposed a practical and economical process for recovery of lead and utilization of waste glass slag.