• 2 The quality of thermosets (crosslinked polymers) is determined by a numerous factors such as the purity of the used monomer, polymerization time and temperature, stoichiometry of comonomers (when used) or type and quantity of catalyst or initiator. (wikipedia.org)
  • At the molecular level, these polymers' molecules are made of long chains of monomer building blocks, the complexity of which increases functionality in many such materials. (sciencedaily.com)
  • Synthetic polymers are made of monomer units linked together like a string of beads," Chen said. (sciencedaily.com)
  • In the simplest polymers, the monomers are identical, but more complex properties arise when polymers contain monomers of different sorts -- called copolymers. (sciencedaily.com)
  • Some modern methods allow scientists to control the arrangement of monomers in a chain, Chen said, but only for very short polymers -- 10 to 20 monomers long. (sciencedaily.com)
  • Ammonium polyphosphates used as flame retardants in polymers have long chains and a specific crystallinity (Form II). (wikipedia.org)
  • DNA and RNA are polymers (in the case of DNA, often very long polymers), and are made up of monomers known as nucleotides . (khanacademy.org)
  • Our comprehensive monomer portfolio enables the synthesis of a variety of polymers with different structures, compositions and properties. (sigmaaldrich.com)
  • CRP can be utilized with a wide range of vinyl monomers to build polymers with diverse properties for different applications. (sigmaaldrich.com)
  • Using a novel polymerization process, MIT chemical engineers have created a new two-dimensional polymer that self-assembles into sheets, unlike all other polymers which form one-dimensional chains. (greencarcongress.com)
  • Polymers, which include all plastics, consist of chains of building blocks called monomers. (greencarcongress.com)
  • While other polymers are made from coiled chains with gaps that allow gases to seep through, the new material is made from monomers that lock together like LEGOs, and molecules cannot get between them. (greencarcongress.com)
  • These molecular modifications result in monomers and resulting polymers with varying proton buffering capacities and hydrolytic profiles. (aiche.org)
  • Crystallization occurs when crystalline polymers are first melted then cooled down slowly, which allows the chains to organize themselves into neatly arranged plates. (materialstoday.com)
  • In other words, groups of monomers are known as polymers. (corrosionpedia.com)
  • In general, polymers such as PVC are referred to as " homopolymers ", as they consist of repeated long chains or structures of the same monomer unit, whereas polymers that consist of more than one monomer unit are referred to as copolymers (or co-polymers). (wikipedia.org)
  • The latter more reliably affords high molecular-weight polymers, but only applies to certain monomers. (wikipedia.org)
  • Step-growth polymers are formed by independent reaction steps between functional groups of monomer units, usually containing heteroatoms such as nitrogen or oxygen. (wikipedia.org)
  • Most step-growth polymers are also classified as condensation polymers , since a small molecule such as water is lost when the polymer chain is lengthened. (wikipedia.org)
  • for example polyurethanes are step-growth polymers formed from isocyanate and alcohol bifunctional monomers) without loss of water or other volatile molecules, and are classified as addition polymers rather than condensation polymers. (wikipedia.org)
  • Polymers, including biopolymers, are made of repetitive units called monomers.Biopolymers inherently have a well defined structure: The exact chemical composition and the sequence in which these units are arranged is called the primary structure. (cichlidresearch.com)
  • Many common polymers (e.g., plastics and resins) are copolymers, consisting of several different types of monomers. (phys.org)
  • The results are connected to the statistical properties of the polymers in the films, where the chain lengths range from short, unentangled to highly entangled. (bvsalud.org)
  • The diisocyanate monomers are important commercially the most important aromatic isocyanates, because the two NCO groups allow them to undergo direct whereas 1,6-HDI, isophorone diisocyanate (IPDI), methyle- polymerization reactions with alcohols to form polyur- nedicyclohexyl diisocyanate (HMDI), and their higher ethanes, in addition to enabling prepolymerization reactions polymers are the most important aliphatic isocyanates. (cdc.gov)
  • Thrombin converts fibrinogen into fibrin monomers, and the fibrin monomers polymerize into fibrin polymers that bind aggregated platelets into platelet-fibrin hemostatic plugs. (msdmanuals.com)
  • In particular, copolymers, which consist of different types of monomers in the same chain, allow for fine-tuning of the material's properties, said Peng Chen, the Peter J.W. Debye Professor of Chemistry in the College of Arts and Sciences (A&S). The monomer sequence plays a critical role in a material's properties, but scientists until now have lacked a method for sequencing synthetic copolymers. (sciencedaily.com)
  • Monomers are also capable of binding to other types of monomers to establish repeating molecule chains. (corrosionpedia.com)
  • At elevated temperatures also the thermal aging plays a role, where unreacted monomer can polymerize and degradation products and other small molecules are released. (wikipedia.org)
  • Its chemical formula is H(NH 4 PO 3 ) n OH showing that each monomer consists of an orthophosphate radical of a phosphorus atom with three oxygens and one negative charge neutralized by an ammonium cation leaving two bonds free to polymerize . (wikipedia.org)
  • Amino acids are regarded as natural monomers which could polymerize on ribosomes in order to build proteins. (corrosionpedia.com)
  • In molecular chemistry, two monomer molecules connected by a strong covalent bond are called a "dimer. (labmanager.com)
  • These chains grow by adding new molecules onto their ends. (greencarcongress.com)
  • A monomer is a type of molecule that may chemically bind to other types of molecules to build a polymer. (corrosionpedia.com)
  • A monomer is any substance containing monomer molecules. (corrosionpedia.com)
  • In polymer chemistry , polymerization ( American English ), or polymerisation ( British English ), is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. (wikipedia.org)
  • [3] molecules consisting of 3 monomer units, which can cyclize to form ring cyclic structures, or undergo further reactions to form tetramers , [3] or 4 monomer-unit compounds. (wikipedia.org)
  • The nucleus itself would be a vast spherical chamber more than a kilometer in diameter, resembling a geodesic dome inside of which we would see, all neatly stacked together in ordered arrays, the miles of coiled chains of the DNA molecules. (uncommondescent.com)
  • Series F. Biotechnologies, Vol. These identical structures, we understand as a unit made up of two or more molecules, join together to form a long chain. (cichlidresearch.com)
  • A polymer is a very large molecule composed of a chain of many (ranging from hundreds to hundreds of thousands) small molecules called monomers that are bonded together. (phys.org)
  • Polymerization is a chemical reaction in which small molecules, called monomers, join together to form a large, interconnected network called a polymer. (nailpro.com)
  • This is in contrast to the much more common peptide ( eupeptide ) bonds between amino acid main chain atoms that form the polypeptide backbones of proteins. (proteopedia.org)
  • An arrow that points from class A to class B indicates that B is a child of A, and therefore that A is a more general class that subsumes B. For example, the class Proteins can be subdivided into the subclasses Polypeptides (monomers) and Protein-Complexes (multimers). (ecocyc.org)
  • A polymer is a material consisting of a large number of repeating subunits, referred to as monomers. (sigmaaldrich.com)
  • The ΔU LH1-RC monomer was half-moon-shaped and contained 11 α- and 10 β-polypeptides, indicating a critical role for protein-U in controlling the number of αβ-subunits required for dimer assembly and stabilization. (nature.com)
  • Chen and colleagues have developed CREATS (Coupled REaction Approach Toward Super-resolution imaging), which allows them to image polymerization catalysis reactions at single-monomer resolution and, through fluorescent signaling, to differentiate monomers from one another. (sciencedaily.com)
  • To make the monomers visible, CREATS couples the polymerization reaction with another reaction that produces fluorescent signals. (sciencedaily.com)
  • Polymerization is a chemical reaction of monomers to form polymer chains or networks. (sigmaaldrich.com)
  • In polymerization, monomers - which have double bonds - are broken down by heat or chemical reaction to single bonds. (firehouse.com)
  • The single bonds attach to each other creating the self-reaction, which in turn creates the long chained polymer. (firehouse.com)
  • Density functional theory calculation was performed to study the photo-activation and radical-monomer addition steps, implying that the reaction energies of these two steps are highly influenced by the penultimate units but in the opposite ways. (rsc.org)
  • Step-growth and chain-growth are the main classes of polymerization reaction mechanisms. (wikipedia.org)
  • Long chains form only late in the reaction. (wikipedia.org)
  • For example, polyester chains grow by reaction of alcohol and carboxylic acid groups to form ester links with loss of water. (wikipedia.org)
  • In chain-growth (or chain) polymerization, the only chain-extension reaction step is the addition of a monomer to a growing chain with an active center such as a free radical , cation , or anion . (wikipedia.org)
  • Long chains are formed from the beginning of the reaction. (wikipedia.org)
  • This reaction results in the formation of strong, interconnected polymer chains, which solidify and harden the glue. (nailpro.com)
  • Hemoglobin adducts were isolated from ethylenediamine teraacetic acid (EDTA)-whole blood, and adducts of acrylamide and glycidamide, at the N-terminal valines of hemoglobin, were cleaved from the protein chain by use of a modified Edman reaction. (cdc.gov)
  • In reality, a polymer is a long-chained molecule composed of many smaller parts called monomers ('mono' is Greek for one). (firehouse.com)
  • Vinyl chloride is also used as an intermediate in the production of other chlorinated compounds and as a component in mixed-monomer plastics. (cdc.gov)
  • The mutant hexokinases bind both glucose 6-phosphate and glucose with high affinity to their N and C-terminal halves, and ADP, also with high affinity, to a site near the N terminus of the polypeptide chain. (rcsb.org)
  • Note that link records involving MSE ( selenomethionine ) generally signify nothing more than MSE being part of a polypeptide chain, but are required because the HETATM MSE residue is covalently linked to the adjacent standard amino acids. (proteopedia.org)
  • It is produced by the copolymerization of trioxan and another monomer. (basf.com)
  • During the copolymerization process, the monomers are stochastically arranged along the main-chain, generating sequence distribution. (phys.org)
  • We offer a comprehensive portfolio of vinyl and norbornene monomers, RAFT agents, ATRP agents and NMP initiators for different types of controlled radical polymerizations. (sigmaaldrich.com)
  • How does the single unit monomer insertion technique promote kinetic analysis of activation and initiation in photo-RAFT processes? (rsc.org)
  • The reversible addition-fragmentation chain transfer (RAFT) agent plays a key role of "photo-iniferter" that is responsible for photo-initiation, chain transfer and termination in most photo-RAFT polymerization systems. (rsc.org)
  • Encouraged by previous works on thermally initiated RAFT polymerization, we herein investigate the kinetics of the early stage of the photo-RAFT process that comprises photo-activation of the initial RAFT agents and addition of RAFT leaving group radicals to the monomers. (rsc.org)
  • To this end, three model RAFT agents with the same terminal units and different penultimate units were synthesized and used as photo-iniferters for further single monomer additions. (rsc.org)
  • The kinetic rate equation reveals that the apparent RAFT consumption rate coefficient is positively correlated to the rate coefficients of photo-dissociation of the RAFT agents ( k d ) and radical-monomer addition ( k p ). (rsc.org)
  • For the contribution to overall RAFT agent consumption rates, the monomer addition is dominant. (rsc.org)
  • A(n)___ is a short chain of monomers not long enough to be considered a polymer. (proprofs.com)
  • These co-monomer units account for the high stability of Ultraform ® during processing and when exposed to long-term heat and to chemicals. (basf.com)
  • Usually, chemical recycling refers to technologies that break down long plastic polymer chains into their basic building blocks by chemical reactions. (basf.com)
  • Monomers, however, are able to hook together into long chains of hundreds or thousands of parts. (firehouse.com)
  • Intermolecular (between molecule) isopeptide bonds that link bacterial pilin monomers into long chains of pili are formed enzymatically by a cysteine transpeptidase "sortase" [3] [4] . (proteopedia.org)
  • With present day computers coupled with efficient parallel molecular dynamics codes, it is now possible to follow the equilibrium dynamics of chains of length $10-20N_e$ from the early Rouse regime to the long time diffusive regime. (aps.org)
  • We show that the effect of salt is non-monotonic and is correlated to the coordination between Li + ions and EO monomers. (nist.gov)
  • It consists of linear chains in which the co-monomers are firmly incorporated in a statistically distributed manner. (basf.com)
  • Addition of 5% of sulphur, enhances the crosslinking of the linear chains and thus improves the stiffening of the rubber for an application like vehicle tires. (cichlidresearch.com)
  • Here we present cryo-EM structures of the native LH1-RC dimer and an LH1-RC monomer lacking protein-U (ΔU). (nature.com)
  • PufX plays a critical role in connecting the two monomers in a dimer, with one PufX interacting at its N-terminus with another PufX and an LH1 β-polypeptide in the other monomer. (nature.com)
  • It is a 160,000-d protein composed of a disulfide-linked dimer with identical polypeptide chains. (medscape.com)
  • This polymerisation route requires neither organometallic monomers nor transition metal catalysts and offers a reliable design strategy to facilitate delocalisation of frontier molecular orbitals, elimination of energetic disorder arising from rotational torsion and allowing closer interchain electronic coupling. (nature.com)
  • A protein, for example, is made of 20 amino acid monomers arranged in a very specific sequence. (sciencedaily.com)
  • Individual chains differ in length, composition and sequence, which requires single-polymer sequencing methods that can resolve and identify individual monomers. (sciencedaily.com)
  • Using CREATS, the researchers can determine the sequence of a polymer as it is made, one monomer at a time, by imaging and identifying every single monomer as it is added to the polymer. (sciencedaily.com)
  • Once the growth of a chain is initiated by formation of an active center, chain propagation is usually rapid by addition of a sequence of monomers. (wikipedia.org)
  • Short sequence quantification via monomer rearrangement into periodic sequences repeating a single codon species. (phys.org)
  • Isocyanates are classified based on the number of N=C=O more aromatic rings) or saturated (aliphatic and alicyclic), groups in the molecule into monoisocyanates (one NCO), the term aliphatic isocyanate referring to saturated isocya- diisocyanate monomers (two NCO), or polyisocyanates nates. (cdc.gov)
  • The main reason is that the monomers are moving from an intermolecular van der Waals distance to covalent distance when a covalent bond is formed during polymerization. (wikipedia.org)
  • Intermolecular (between molecule) "chain mail" isopeptide bonds in the capsid of bacteriophage HK97 [7] . (proteopedia.org)
  • One protein-U was only partially resolved in the dimeric structure, signaling different degrees of disorder in the two monomers. (nature.com)
  • Analysis of polypeptide inter-chain entanglements using swelling dynamics of a spin coated protein layer. (acs.org)
  • In chemical recycling, the polymer chains of the plastics are chemically broken down into basic building blocks that can be used as raw materials by the chemical industry (e.g., syngas, pyrolysis oil, monomers), which can then be used to make products with the same quality as those made from fossil resources. (basf.com)
  • In this process, plastics are broken down into their monomers, from which the polymer can be rebuilt. (basf.com)
  • In the branched cases some monomers are missing the ammonium anion and instead link to three other monomers. (wikipedia.org)
  • In our recent study [6], the side chain length was varied to include either one or two alkyl spacers denoted between the amine and the carboxylate/ester groups. (aiche.org)
  • The Carling facility produces acrylic monomers used in performance coatings, adhesives, water treatment and other performance materials used in various applications. (icis.com)
  • Monomers are commonly used for coatings in industry. (corrosionpedia.com)
  • Coatings are typically waterborne suspensions that may combine with hard monomers like methyl methacrylate (MMA) and a softer one like acrylate monomer to enhance flexibility of coatings. (corrosionpedia.com)
  • Our offering is organized by their functional groups, and major monomer categories include acrylics, alcohols, epoxide and amines. (sigmaaldrich.com)
  • We propose that the BPTI decamer, with a heparin chain threading the decamer channel, plays a functional role in the mast cell. (lu.se)
  • Exposure of the monomer crystals to ADP in the complete absence of glucose 6-phosphate reveals a second binding site for adenine nucleotides at the putative active site (C-half), with conformational changes extending 15 A to the contact interface between the N and C-halves. (rcsb.org)
  • LONDON (ICIS)-Arkema is investing €130m in a new purification process to cut carbon dioxide (CO2) emissions by 20% at its Carling acrylic monomers production site in France, it said on Wednesday. (icis.com)
  • After the introduction of biobased acrylic monomers in 2022 using the mass balance approach, this new project at Carling is another key step to position Arkema as a leader in low-carbon acrylic materials, and to help our customers reduce their Scope 3 emissions," said Richard Jenkins, senior vice-president for Arkema's Coating Solutions. (icis.com)
  • The main component of these glues is an acrylic monomer called cyanoacrylate. (nailpro.com)
  • The activator contains a substance similar to curing agent in acrylic liquid monomers. (nailpro.com)
  • For bulk polymer melts, the relation between the chain length and Tg follows the Fox-Flory equation. (bvsalud.org)
  • To produce coupling agents and compatibilizers, polyolefins (polypropylene, polyethylene, elastomers) are often used in reactive extrusion processes with unsaturated (polar) monomers. (fraunhofer.de)
  • 23 It can be seen that the distance between to monomers changes from van der Waals distance (3.40 Å) to covalent distance of a single bond (1.54 Å), leading to a net change of -1.86 Å. (wikipedia.org)
  • Disulfide bonds are a much more common form of covalent linkage between polypeptide chains. (proteopedia.org)
  • Expandable monomers occupy after polymerization a greater volume than before and were designed to counteract the volumetric shrinkage upon addition. (wikipedia.org)
  • Our study reveals the explicit contribution of the side chain and backbone residues in influencing the determination of the glass transition temperature. (bvsalud.org)
  • Polymer properties and performances are highly dependent on monomer types and the polymerization tools or methods used for the synthesis. (sigmaaldrich.com)
  • In conclusion, the multifaceted data support a rosette CSC with 18 CESAs that mediates the synthesis of a fundamental microfibril composed of 18 glucan chains. (osti.gov)
  • There is a direct relationship between segmental dynamics measured on the monomer length scale and ion transport under an applied field on macroscopic length scales. (nist.gov)
  • Though these early simulations were limited to chains of a few $N_e$, they demonstrated the potential of computer simulations to contribute to our understanding of polymer dynamics. (aps.org)
  • Further evidence for the tube models of polymer dynamics has been obtained by identifying the primitive path mesh that characterizes the microscopic topological state of the computer- generated conformations of the chains. (aps.org)
  • The glass transition temperature of confined and free-standing polymer films of varying thickness is studied by extended molecular dynamics simulations of bead-spring chains. (bvsalud.org)
  • The monomer exists in a liquid form, allowing it to flow and penetrate into small gaps or pores. (nailpro.com)
  • An isopeptide bond is an amide bond between the sidechain of one amino acid and the sidechain or main chain terminus of another amino acid, or a ligand. (proteopedia.org)
  • 1000), [1] but short polymer chains ( e.g. pyro-, tripoly-, and tetrapoly-) are more soluble and show increasing solubility with increasing chain length. (wikipedia.org)
  • This research team recently developed the world's first practical polymer sequencer quantifying the short monomer segments in specific sequences, herein called "codon" using an analogy from nucleotide triplets, via pyrolysis mass-spectra. (phys.org)
  • We first discuss short lattice chains, in order to compare with exact data and with other methods. (lu.se)
  • When the anionic carboxylate groups in zwitterionic PCB side chains are esterified, the polymer is rendered cationic and thus able to bind and condense nucleic acids. (aiche.org)
  • For the monomer building blocks, they use a compound called melamine, which contains a ring of carbon and nitrogen atoms. (greencarcongress.com)
  • The number of CESAs in the CSC has been debated for decades in light of changing estimates of the diameter of the smallest microfibril formed from the β-1,4 glucan chains synthesized by one CSC. (osti.gov)
  • Polypropylene (PP)/ethylene propylene diene monomer (EPDM)/ graphene nanosheets (GNs) were compounded by a two-step melt mixing process via an internal mixer (brabender plasticorder). (degruyter.com)
  • The highest acrylamide and glycidamide adduct levels were found among monomer production process operators. (cdc.gov)
  • The material obtained from depolymerization therefore re-enters the chemical value chain at a later stage than pyrolysis oil or syngas. (basf.com)
  • The precise arrangement of the monomers in a copolymer plays an important role in its properties, such as stiffness or flexibility. (sciencedaily.com)
  • The properties of ammonium polyphosphate depend on the number of monomers in each molecule and to a degree on how often it branches. (wikipedia.org)
  • The effect of GNs, graphene oxide (GOSs) and graphene oxide functionalized with PP chains (PP-g-GOSs) on various blend properties were investigated. (degruyter.com)
  • We employ the single unit monomer insertion (SUMI) technique to simplify and slow down these processes, in which chain propagation is absent. (rsc.org)
  • An example of alkene polymerization , in which each styrene monomer's double bond reforms as a single bond plus a bond to another styrene monomer. (wikipedia.org)