Polymerization - Science topic

This article presents the results of experiments and finite element analysis on a hybrid polymer gear concept. The study aimed to investigate the effectiveness of the hybrid gear concept by using a rack tooth geometry. The results of the experiments have shown that the hybrid gear concept improves the heat evacuation from the flank and root regions...

The thermal stability of the SiC ultrafine fibers is affected due to the large amounts of oxygen introduced during the oxidative curing process. In this work, cyano-polycarbosilane (PCSCN) and cyano-polyaluminocarbosilane (PACSCN) are synthesized by hydrosilylation reaction between PCS and acrylonitrile using a common radical initiator 2,2-azodiiso...

Non-singular black holes models can be described by modified classical equations motivated by loop quantum gravity. We investigate what happens when the sine function typically used in the modi- fication is replaced by an arbitrary bounded function, a generalization meant to study the effect of ambiguities such as the choice of representation of th...

Breast cancer, one of the most common types of cancer worldwide, has a high degree of malignancy while lacking efficient treatments. The off-target events frequently occurring in drug administration have been a major obstacle, which causes severe side effects to patients and reduces the therapeutic efficacy. An ideal medication should precisely tar...

Step lap joints are kinds of lap structures, where butted laminations of each layer are consecutively offset in succeeding layers in the same direction. They are mainly designed this way to reduce the peel stresses at the edges of the overlap area observed in single lap joints. In their service, lap joints are often subjected to bending loads. Howe...

This study investigates the influence of temperature and loading rate on the Mode I and Mode II interlaminar fracture behavior of carbon-nanotubes-enhanced carbon-fiber-reinforced polymer (CNT-CFRP). CNT-induced toughening of the epoxy matrix is characterized by producing CFRP with varying loading of CNT areal density. CNT-CFRP samples were subject...

Synthetic high-performance fibers present excellent mechanical properties and promising applications in the impact protection field. However, fabricating fibers with high strength and high toughness is challenging due to their intrinsic conflicts. Herein, we report a simultaneous improvement in strength, toughness, and modulus of heterocyclic arami...

Polymeric wet-strength agents are important additives used in the paper industry to improve the mechanical properties of paper products, especially when they come into contact with water. These agents play a crucial role in enhancing the durability, strength, and dimensional stability of paper products. The aim of this review is to provide an overv...

Polyurethane grouting material (polymer) has been widely used in rock mass fracture grouting. The previous test of polymer slurry grouting in planar fracture did not consider the influence of temperature; therefore, in this paper, a test of polymer slurry grouting in planar fracture was firstly conducted in order to explore the diffusion characteri...

The possibility of exploiting visible light to induce polymerizations is extremely appealing from a technological point of view as it improves the sustainability of the overall process. To achieve this objective, it is necessary to employ single- or multicomponent systems containing a photoinitiator, and in some cases, a photosensitizer in combinat...

Recent experimental results [Liu and Broer, Nat. Commun. 6 8334 (2015)] reveal that light-responsive azo-doped liquid crystal polymers under dual-wavelength illumination exhibit a significant reduction in density. This reduction in density was attributed to dynamic trans-cis-trans isomerization cycles. The light-induced isomerization kinetics sugge...

In this research, the fracture behavior of brittle specimens weakened by V-shaped notches with end holes (VO-notches) is studied. Firstly, an experimental investigation is conducted to eval-uate the effect of VO-notches on the fracture behavior. To this end, VO-notched samples of PMMA are made and exposed to pure opening mode loading, pure tearing...

The investigation of the bandwidth in multimode graded-index microstructured polymer optical fiber (GI mPOF) with a solid core is proposed using a modal diffusion approach. For a variety of launch radial offsets of multimode GI mPOF, bandwidth is reported by numerically solving the time-dependent power flow equation (TD PFE) using the explicit fini...

The current investigation is focused on the development of composite membranes based on polymeric ionic liquids (PILs) containing imidazolium and pyridinium polycations with various counterions, including hexafluorophosphate, tetrafluoroborate, and bis(trifluoromethylsulfonyl)imide. A combination of spectroscopic methods was used to identify the sy...

PROCEEDINGS OF THE 36TH CONFERENCE OF THE POLYMER PROCESSING SOCIETY – PPS36

3D-printed firearms cause a considerable problem in criminal investigations because, in addition to being "ghost guns," they may not produce all the conventional ballistic traces normally used in firearm identification. However, these firearms do generate other types of trace evidence, such as polymer traces from the polymer used to print the firea...

Biodegradable polymer berbahan dasar pati merupakan alternatif polymer ramah lingkungan yang dikembangkan untuk mengatasi permasalahan yang ditimbulkan oleh bahan – bahan polymer sekali pakai berbahan dasar minyak bumi. Biodegradable polymer dengan bahan dasar pati memiliki kelemahan antara lain nilai water vapor permeability dan water absorption n...

Intelligent polymer gel, as a popular polymer material, has been attracting much attention for its application. An intelligent polymer gel will make corresponding changes to adapt to the environment after receiving stimuli; therefore, an intelligent polymer gel can play its role in many fields. With the research on intelligent polymer gels, there i...

Abstract Segmented polyurethanes based on poly(l-lactide)diol - PLLA, poly(ethylene-glycol) - PEG, poly(trimethylene-carbonate)diol - PTMC and hexamethylene diisocyanate were synthesized by a two-step polyaddition. Polyurethanes with variable compositions and molar mass were semi-crystalline and presented PLLA or PLLA + PEG crystalline phases and a...

Herein, we designed and synthesized two novel donor-acceptor1-acceptor2-acceptor1 (D-A1-A2-A1) type random conjugated terpolymers, DTP-TPD-DPP and DTP-TPD-BT, as a donor component for single-junction non-fullerene organic solar cells. The terpolymers were randomly combined from N-aryldithienopyrrole (DTP) donor unit and N-alkylthienopyrroledione (T...

In this work, hydroxylated compounds are applied to prepare polymer-dispersed liquid crystal (PDLC) films and the role of the hydroxy group is studied in detail by comparing the effects of the hydroxylated acrylate monomer, the hydroxylated mesogenic component and their corresponding non-hydroxylated components. It is revealed that the hydroxylated...

Via large-scale molecular dynamics simulations, we observe the melting of a topological glass of stiff ring polymers by incorporating flexible ring polymers, along an isobaric path. As more flexible ring polymers are introduced, cluster glass-like structures emerge in the stiffer ring polymers with reduced orthogonal threading. This eventually evol...

Carbon nanotube-reinforced polymer composites have shown great potential for use in energy harvesting applications due to their unique properties, such as high electrical conductivity and mechanical strength. In this study, we investigated the performance of carbon nanotube-reinforced polymer composites for energy harvesting applications. We fabric...

The purpose of the study was to assess the growth of Candida Albicans on Polymethylmethacrylate(PMMA) as a denture base, using various curing cycles. Total 200 samples of denture bases were prepared divided into five categories, cut into 2×2 cm, with the thickness of 1.0 mm for the analysis. 160 out of them were further divided into 4 groups for he...

Since the first introduction of their concept in the 1980s and 90s, polymer brushes have been the focus of intense research efforts to identify novel physico-chemical properties and responsiveness, and optimise the properties of associated interfaces for an ever growing range of applications. To a large extent, this effort has been enabled by progr...

(1) Background: This study aimed to determine the effect of repeated pre-polymerization heating on the color and translucency of a one-shaded resin-based composite and to evaluate whether the heating cycles affect its color stability. (2) Methods: Fifty-six samples of 1-mm thickness were fabricated from Omnichroma (OM) after applying different heat...

The kinetic features of change in the strength of oriented polypropylene (PP) as a result of radiation oxidation have been established. The relationship between the change in the strength of oriented PP (slit-film yarns) after irradiation in air and the structural characteristics of the polymer is shown. A kinetic model is presented that takes into...

In this study, we synthesized radioexcitable luminescent polymer dots (P-dots) doped with heteroleptic tris-cyclometalated iridium complexes that emit red, green, and blue light.

Ceramic tile adhesives (CTA) are playing a dominant role for the business of dry-mix producers. Their quality is classified according to EN 12004. In addition, this standard describes the procedure of a CTA’s performance evaluation. Therefore, a defined ceramic tile, a concrete substrate, and the actual tile adhesive is required. In our study, we i...

Fluorinated hard carbon materials have been considered to be a good candidate of cathode materials of Li/CFx batteries. However, the effect of the precursor structure of the hard carbon on the structure and electrochemical performance of fluorinated carbon cathode materials has yet to be fully studied. In this paper, a series of fluorinated hard ca...

The purpose of this paper is to study a one-dimensional polymer penalized by its range and placed in a random environment $\omega$. The law of the simple symmetric random walk up to time $n$ is modified by the exponential of the sum of $\beta \omega_z - h$ sitting on its range, with~$h$ and $\beta$ positive parameters. It is known that, at first or...

This study describes the development and implementation of a lab-scale four-needle nosepiece for solution blowing, which enabled the investigation of the roping probability of four polymer jets at different inter-needle distances and air velocities. The roping probabilities of the four jets were compared to the corresponding roping probabilities of...

The aim of the work was to investigate how the ethylene atmosphere during irradiation affects some of its functional properties. It was assumed that the atmosphere of ethylene during irradiation would prevent the formation of oxygen-derived free radical adducts and this way the oxygen-driven oxidation would be blocked by ethylene molecules. The pre...

Hydrogels are three-dimensional polymer networks derived from hydrophilic macromonomers, which can be categorized as natural, synthetic, or hybrid hydrogels [...]

Identifying changes in the nanoscopic domain is a key challenge in the physicochemical sciences, where great interest is on sensing complex processes that involve cellular biochemical reactions, chemical heterogeneities, contact forces, and other interfacial phenomena. This has stimulated the development of diverse materials that allow subtle nanos...

We report a new computational approach to model hard-soft block copolymers like polyurea as a liquid crystalline polymer to understand their microstructural evolution due to mechanical loading. The resulting microstructure closely resembles the microstructure observed in polyurea. The stress-strain relations in uniaxial compression and tension load...

Journal of Inorganic and Organometallic Polymers and Materials

Polymers confined in corrugated channels, i.e. channels of of varying amplitude, display, upon increasing their degree of polymerization $N$, a non-monotonic behavior in the diffusion coefficient. We propose a theoretical effective free energy for linear polymers based on a Fick-Jacobs approach. We validate the predictions against numerical data, o...

The influence of seed topologies on seeded supramolecular polymerization was examined using helicoidal and toroidal supramolecular polymer seeds. The addition of these seeds to a supersaturated solution of monomers led to distinct nucleation-growth kinetics, which were attributed to the significant difference between the elongation from helicoid te...

Polymeric wet-strength agents are important additives used in the paper industry to improve the mechanical properties of paper products, especially when they come in contact with water. These agents play a crucial role in enhancing the durability, strength, and dimensional stability of paper products. The aim of this review is to provide an overvie...

This review describes the recent research and development progress in the radical polymerization of bio-based monomers in aqueous dispersed media. The previous review on this subject was published in 2019 by S. Molina-Gutiérrez and coworkers (Green Chem., 2019, 21, 36). This topic is constantly evolving and improving because of the need for greener...

Aндреевна Зенитова (ORCID 0000-0001-9650-9343) Казанский национальный исследовательский технологический университет, ул. К. Маркса, 68, Казань, Проблема замены упаковки для пищевых продуктов, получаемой из синтетических полимеров, на биоразлагаемые пленочные материалы, производимые на основе природного сырья, является чрезвычайно актуальной, что св...

In this talk we present fast, accurate, neural networks for target identification in hyperspectral imaging with a focus on connecting the architecture and parameters of the network with the physics of the target materials. Molecular bonds present in the material have vibrational frequencies affecting the amount of light reflected per wavelength, wh...

The catalytic properties of Seqenzym® FT, a fungal fructosyltransferase heterologously expressed in yeasts, were investigated at a temperature of 55 °C and pH 5.5. The initial rate measurements showed that the transfructosylation rate was only slightly inhibited by sucrose above the concentration of 1.5 M. A rather low level of hydrolytic side acti...

This article reviews the present status and prospects of sustainable bamboo fiber reinforced polymeric composites (BFRCs). Because of its rapid growth, renewability, and minimal environmental effect, bamboo has emerged as a viable contender in response to the increasing demand for eco-friendly materials across a variety of sectors. Bamboo is going...

he purpose of this work was to investigate and develop a method for the formation of effective DM-legnine and Na-КМЦ on the acetate-cellulose membrane of the UAM-100 tank, as well as to measure the adsorption equilibrium of a solution with variable concentrations of the substances under study, shaking with a suspension of the acetate-cellulose memb...

Infections caused by Klebsiella pneumoniae continue to be a global public health threat; the treatment of these infections is complicated by the high frequency of multidrug resistance. K. pneumoniae produces a polysaccharide capsule required for virulence. Hypervirulent isolates also have a hypermucoviscous (HMV) phenotype that increases virulence,...

Silicon is typically found in the form of insoluble crystalline aluminosilicates, which plants cannot use. Only monosilicic acid or orthosilicic acid (H4SiO4) are absorbed. Both are highly unstable, polymerizing into an unavailable form, polymeric silicic acid, or forming compounds with other chemicals to make metasilicates. Silicon has emerged...

An extensive review of literature simulations of polymer melts is given, considering results that test aspects of the Rouse model in the melt. We focus on the mean-square amplitudes < (X_p(0))^{2} > and time correlation functions < X_p(0) X_p(t) > of the Rouse modes $X_p(t)$. Contrary to the Rouse model: (i) Mean-square Rouse mode amplitudes < (X_p...

Controlled polymerization methods are well-established synthetic protocols for the design and preparation of polymeric materials with a high degree of precision over molar mass and architecture. Exciting recent work has shown that the high end-group fidelity and/or functionality inherent in these techniques can enable new routes to depolymerization...

The present work continues our previous studies of pom-pom molecule [K. Haydukivska, O. Kalyuzhnyi, V. Blavatska, and J. Ilnytskyi, J. Mol. Liq. 328, 115456 (2021); Condens. Matter Phys. 25, 23302 (2022)]. The molecule consists of a linear backbone with two branching points at both ends, with functionalities f1 and f2. Here, the main attention is c...

When the length scale of external stimulations is comparable to most chain lengths within a poly-meric solid, the nonlocal and microstructure-dependent strain-gradient effects become significant. The present work proposes a physically-based nonlocal strain gradient theory of polymer networks, where the kernel functions and intrinsic length scales h...

A new device and procedure for the in situ quantification of the extent of the self-healing and the kinetics of self-healing of polymeric materials were proposed. The device consisted of flowing an inert gas below the sample placed in a hermetically closed chamber. When the sample was perforated/damaged, the gas passed through the hole made in the...