Frontal polymerization approach reduces energy use significantly

Extracytoplasmic sugar decoration of glycopolymer components of the bacterial cell wall contributes to their structural diversity. Typically, the molecular mechanism that underpins such a decoration process involves a three-component glycosylation system (TGS) represented by an undecaprenyl-phosphate (Und-P) sugar-activating glycosyltransferase (Und-P GT), a flippase, and a polytopic glycosyltransferase (PolM GT) dedicated to attaching sugar residues to a specific glycopolymer. Here, using bioinformatic analyses, CRISPR-assisted recombineering, structural analysis of cell wall–associated polysaccharides (CWPS) through MALDI-TOF MS and methylation analysis, we report on three such systems in the bacterium Lactococcus lactis. On the basis of sequence similarities, we first identified three gene pairs, csdAB, csdCD, and csdEF, each encoding an Und-P GT and a PolM GT, as potential TGS component candidates. Our experimental results show that csdAB and csdCD are involved in Glc side-chain addition on the CWPS components rhamnan and polysaccharide pellicle (PSP), respectively, whereas csdEF plays a role in galactosylation of lipoteichoic acid (LTA). We also identified a potential flippase encoded in the L. lactis genome (llnz_02975, cflA) and confirmed that it participates in the glycosylation of the three cell wall glycopolymers rhamnan, PSP, and LTA, thus indicating that its function is shared by the three TGSs. Finally, we observed that glucosylation of both rhamnan and PSP can increase resistance to bacteriophage predation and that LTA galactosylation alters L. lactis resistance to bacteriocin.

ವಿಶಾಖಪಟ್ಟಣದಲ್ಲಿ ಗುರುವಾರದ ಅನಿಲ ಸೋರಿಕೆ ಘಟನೆಯು ಕನಿಷ್ಠ ಎಂಟು ಮಂದಿಯ ಪ್ರಾಣ ತೆಗೆದಿದೆ. ನೂರಾರು ಮಂದಿ ಅಸ್ವಸ್ಥರಾಗಿದ್ದಾರೆ. ಈ ಘಟನೆಯ ಮೂಲ ಇರುವುದು ಎಲ್.ಜಿ. ಪಾಲಿಮರ್ಸ್ ಒಡೆತನದ ಕಾರ್ಖಾನೆಯಲ್ಲಿ. ಪ್ಲಾಸ್ಟಿಕ್ ರಿಸಿನ್ ಮತ್ತು ಸಿಂಥೆಟಿಕ್ ಫೈಬರ್ ಉತ್ಪಾದನೆ ಮಾಡುವ ಕೈಗಾರಿಕೆಯ ಒಂದು ಭಾಗವಷ್ಟೇ ಈ ಘಟಕ. ಇನ್ನು ಇದರ ಮಾಲೀಕತ್ವ ಯಾರದು ಅಂತ ನೋಡಿದರೆ, ದಕ್ಷಿಣ ಕೊರಿಯಾದ

On May 7, 11 persons were killed while over 1,000 were hospitalised due to gas leakage from LG Polymers chemical plant at RR Venkatapuram in Andhra Pradesh's Visakhapatnam.

Vizag gas leak: LG Polymers issues official statement, says doing our...

‘TDP president politicising the gas leak tragedy’

Visakhapatnam gas leak: LG Polymers apologises, offers ‘every support’ to affected

The asymmetric units of the title compounds, namely, catena-poly[[(1,4,8,11-tetra­aza­cyclo­tetra­decane-κ4N1,N4,N8,N11)nickel(II)]-μ-1,3-bis­(3-carboxyl­ato­prop­yl)tetra­methyl­disiloxane-κ2O:O'], [Ni(C10H24O5Si2)(C12H24N4)]n (I), and catena-poly[[[(1,4,8,11-tetra­aza­cyclo­tetra­decane-κ4N1,N4,N8,N11)nickel(II)]-μ-4-({[(3-carb­oxy­prop­yl)di­methyl­sil­yl]­oxy}di­methyl­sil­yl)butano­ato-κ2O:O'] per­chlorate], {[Ni(C10H25O5Si2)(C12H24N4)]ClO4}n (II), consist of one (in I) or two crystallographically non-equivalent (in II) centrosymmetric macrocyclic cations and one centrosymmetric dianion (in I) or two centrosymmetric monoanions (in II). In each compound, the metal ion is coordinated by the four secondary N atoms of the macrocyclic ligand, which adopts the most energetically stable trans-III conformation, and the mutually trans O atoms of the carboxyl­ate in a slightly tetra­gonally distorted trans-NiN4O2 octa­hedral coordination geometry. The crystals of both types of compounds are composed of parallel polymeric chains of the macrocyclic cations linked by the anions of the acid running along the [101] and [110] directions in I and II, respectively. In I, each polymeric chain is linked to four neighbouring ones by hydrogen bonding between the NH groups of the macrocycle and the carboxyl­ate O atoms, thus forming a three-dimensional supra­molecular network. In II, each polymeric chain contacts with only two neighbours, forming hydrogen bonds between the partially protonated carb­oxy­lic groups of the bridging ligand. As a result, a lamellar structure is formed with the layers oriented parallel to the (1overline{1}1) plane.

The two new pyrazine­ophanes, 5,7-di­hydro-1H,3H-dithieno[3,4-b:3',4'-e]pyrazine, C8H8N2S2, L1, and 3,4,8,10,11,13-hexa­hydro-1H,6H-bis­([1,4]di­thio­cino)[6,7-b:6',7'-e]pyrazine, C12H16N2S4, L2, both crystallize with half a mol­ecule in the asymmetric unit; the whole mol­ecules are generated by inversion symmetry. The mol­ecule of L1, which is planar (r.m.s. deviation = 0.008 Å), consists of two sulfur atoms linked by a rigid tetra-2,3,5,6-methyl­ene­pyrazine unit, forming planar five-membered rings. The mol­ecule of L2 is step-shaped and consists of two S–CH2–CH2–S chains linked by the central rigid tetra-2,3,5,6-methyl­ene­pyrazine unit, forming eight-membered rings that have twist-boat-chair con­fig­urations. In the crystals of both compounds, there are no significant inter­molecular inter­actions present. The reaction of L1 with silver nitrate leads to the formation of a two-dimensional coordination polymer, poly[(μ-5,7-di­hydro-1H,3H-dithieno[3,4-b;3',4'-e]pyrazine-κ2S:S')(μ-nitrato-κ2O:O')silver(I)], [Ag(NO3)(C8H8N2S2)]n, (I), with the nitrato anion bridging two equivalent silver atoms. The central pyrazine ring is situated about an inversion center and the silver atom lies on a twofold rotation axis that bis­ects the nitrato anion. The silver atom has a fourfold AgO2S2 coordination sphere with a distorted shape. The reaction of L2 with silver nitrate also leads to the formation of a two-dimensional coordination polymer, poly[[μ33,4,8,10,11,13-hexa­hydro-1H,6H-bis­([1,4]di­thio­cino)[6,7-b;6',7'-e]pyrazine-κ3S:S':S''](nitrato-κO)silver(I)], [Ag(NO3)(C12H16N2S4)]n, (II), with the nitrate anion coordinating in a monodentate manner to the silver atom. The silver atom has a fourfold AgOS3 coordination sphere with a distorted shape. In the crystals of both complexes, the networks are linked by C—H⋯O hydrogen bonds, forming supra­molecular frameworks. There are additional C—H⋯S contacts present in the supra­molecular framework of II.

The study, published today in Nature Microbiology, holds promise for a new treatment method against antibiotic-resistant bacteria (commonly known as superbugs).

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Soil stabilisation and the process of strengthening the physical properties of soil is fundamental to the construction process of infrastructure such as roads, runways and earth dams. Many chemical additives currently used in soil stabilisation are associated with adverse environmental effects and this study examines the use of biopolymers, such as xanthan gum and guar gum, as more sustainable alternatives. The researchers have run a series of laboratory experiments to evaluate the viability of these two types of biopolymers for use as additives for collapsible soil stabilisation, and found that both could be used in place of conventional additives to improve soil strength, permeability and collapse potential.

The unit of South Korean chemical giant LG Chem said it is committed to working closely with the concerned authorities to investigate the cause of the incident, prevent recurrence in future and secure the foundation for care and treatment. The firm said a special task force has been set up to help victims and families to resolve any issues.

Vizag gas leak tragedy: Tension at LG Polymers plant as villagers protest demanding its closure

A 1,3-diketoamide functional monomer represented by the following formula (1): wherein R and Y are independently selected from the group consisting of hydrogen, an alkyl group having from 1 to 10 carbon atoms, an aryl group having from 6 to 20 carbon atoms, and an aralkyl group having from 7 to 20 carbon atoms; and wherein X and Z are independently selected from the group consisting of an alkyl group having from 1 to 10 carbon atoms, an aryl group having from 6 to 20 carbon atoms, and an aralkyl group having from 7 to 20 carbon atoms. Also disclosed are emulsion, suspension, and solution polymers comprising residues from the 1,3-diketoamide functional monomer of formula 1 and, optionally, one or more additional ethylenically unsaturated monomers. Both latex and self-curing coating compositions described herein exhibit excellent hydrolytic stability, including increased retention of 1,3-diketo functionality.

An aqueous dispersion includes particles at least partially encapsulated in a microgel where the microgel is prepared from a hyperbranched acrylic polymer. In addition, a method for making an aqueous dispersion includes: (1) mixing in an aqueous medium: (a) particles, (b) at least one ethylenically unsaturated monomer, and (c) a water-dispersible hyperbranched acrylic polymer having ethylenic unsaturation; and (2) polymerizing the at least one ethylenically unsaturated monomer and water-dispersible hyperbranched acrylic polymer having ethylenic unsaturation to at least partially encapsulate the particles in a microgel.

Non water-soluble polymers with a comb structure and a (meth)acrylic skeleton on which are grafted side chains containing at least one hydrophobic monomer of the styrene or (meth)acrylic ester type on C1 to C4, and at least one hydroxy or methoxy polylakylene glycol monomer. The levels of monomers are such that the polymer is amphiphilic because it is both rich in hydrophobic monomer and polylakylene glycol monomer. These products, used in paper coating dispersions, enable an increase in their Brookfield™ viscosity, a reduction in their ACAV viscosity, and an improvement in their water retention, which makes them particularly well suited for dry extract and/or high deposit speed coatings.

This invention relates to a process for polymerizing ethylene comprising contacting ethylene and optional comonomers with a catalyst system comprising an activator and a transition metal compound represented by the formula: ##STR1## Wherein R1 and R2 are independently hydrogen or a group having up to 100 carbon atoms, Cp1 is a bulky ligand; Cp2 is a bulky ligand or a heteroatom optionally bound to a C1 to C50 hydrocarbyl group, n is the valence state of the transition metal, Tm is a Group 3 to 10 metal, and each X is independently an anionic leaving group.

A metallocene compound is provided wherein to a transition metal compound is bonded a multidentate compound wherein a substituted cycloalkadienyl ring CA1 having therein a heteroaromatic group Ra containing an oxygen, sulfur or nitrogen atom on a cycloalkadienyl ring, preferably the five-membered ring thereof, and an unsubstituted or substituted cycloalkadienyl group CA2 or --(R1)N--, --O--, --S-- or --(R1)P--, preferably CA2, more preferably a substituted cycloalkadienyl group identical with CA1 are bonded through a divalent linking group. The metallocene compound is suitable as a principal ingredient of a catalyst for the polymerization of olefins, particularly achieving a very high effect in making the molecular weight of a polypropylene higher.

The present invention relates to epoxy group-terminated polymers of the formula (I). Said epoxy group-terminated polymers are suited extremely well as impact resistance modifiers, particularly in epoxy resin compositions. They are particularly suited for use in heat-curing epoxy resin adhesives. It has been found that such epoxy resin compositions not only have excellent mechanical properties and high glass transition temperatures, but also above all improved impact resistance properties, both at room temperature and at low temperatures.

The invention is directed to a matting and/or frosting additive concentrate for polymers or polymer blends, said additive comprising to 75% by weight of hollow glass microspheres and 20 to 95% by weight of a liquid or waxy carrier material and optionally up to 75% by weight of additives.

Aqueous copolymer dispersions for a variety of uses, including coating compositions or binders for plasters and paints, are disclosed. The aqueous copolymer dispersions may comprise one or more silicon containing compounds, in particular hydrolyzable silane compounds without any additional reactive group.

The invention provides a process for monitoring and/or adjusting a dispersion polymerization of an olefin-based polymer, the process comprising monitoring the concentration of the carbon-carbon unsaturations in the dispersion using Raman Spectroscopy. The invention also provides a process for polymerizing an olefin-based polymer, the process comprising polymerizing one or more monomer types, in the presence of at least one catalyst and at least one solvent, to form the polymer as a dispersed phase in the solvent; and monitoring the concentration of the carbon-carbon unsaturations in the dispersion using Raman Spectroscopy.

The present invention provides a polymerization reactor for producing a super absorbent polymer comprising: a reaction unit; a monomer composition supply unit being connected to the reaction unit and supplying a monomer composition solution containing a monomer, a photoinitiator, and a solvent; an agitating shaft extended in the reaction unit from one end of the reaction unit connected to the monomer composition supply unit to the other end of the reaction unit; a plurality of agitating blades installed around the agitating shaft; and a light irradiation unit providing light to the monomer composition solution furnished from the monomer composition supply unit, and a method of producing super absorbent polymers by using the same.

A variety of biomedical devices are provided which include thiol-ene or thiol-yne shape memory polymers. The biomedical devices of the invention are capable of exhibiting shape memory behavior at physiological temperatures and may be used in surgical procedures. Methods of making the devices of the invention are also provided.

A process for the preparation of modified polymers by a photo-initiated polymerization includes preparing a polymerization medium comprising at least one photoinitiator comprising at least one phosphorous oxide (P═O) group or at least one phosphorous sulfide (P═S) group, and at least one polymerizable monomer. The at least one polymerizable monomer is polymerized by irradiating the polymerization medium with electromagnetic radiation so as to induce a generation of radicals so as to obtain a polymer. The polymer is modified by irradiating the polymer with electromagnetic radiation so as to induce a generation of radicals from the polymer in a presence of at least one modifying agent.

The invention relates to polymers that can be obtained by polymerizing the monomers (A), (B), and (D), and optionally (C), where (A) is a monomer of formula (I), wherein A stands for C2 to C4 alkylene, B stands for a C2 to C4 alkylene different from A, R stands for hydrogen or methyl, m stands for a number from 1 to 500, n stands for a number from 1 to 500, (B) is an ethylenically unsaturated monomer that contains at least one carboxylic acid function, (C) is optionally a further ethylenically unsaturated monomer different from (A) and (B), (D) is a monomer of formula (II), wherein D stands for C2 to C4 alkylene, E stands for a C2 to C4 alkylene group different from D, F stands for a C2 to C4 alkylene group different from E, R stands for hydrogen or methyl, o stands for a number from 1 to 500, p stands for a number from 1 to 500, q stands for a number from 1 to 500, and wherein the weight fraction of the monomers is 35 to 99% for the macromonomer (A), 0.5 to 45% for the monomer (B), 0 to 20% for the monomer (C), and 1 to 20% for the monomer (D), and to the use of said polymers as defoamers for inorganic solid suspensions.

Oil-water dispersions and emulsions derived from petroleum industry operations are demulsified and clarified using anionic polymers. Formation of such oil-water dispersion and emulsions is inhibited and mitigated using the anionic polymers. The anionic polymers comprise: A) 2-80% by weight of at least one C3-C8 α,β-ethylenically unsaturated carboxylic acid monomer; B) 15-80% by weight of at least one nonionic, copolymerizable α,β-ethylenically unsaturated monomer; C) 1-50% by weight of one or more of the following monomers: C1) at least one nonionic vinyl surfactant ester; or C2) at least one nonionic, copolymerizable α,β-ethylenically unsaturated monomer having longer polymer chains than monomer B), or C3) at least one nonionic urethane monomer; and, optionally, D) 0-5% by weight of at least one crosslinker.

A cleansing composition for cosmetic or household use may include an ampholytic polymer; a crosslinked cationic polymer; a surfactant component selected from the group consisting of anionic surfactants, amphoteric surfactants, cationic surfactants, nonionic surfactants, and zwitterionic surfactants; and an aqueous and/or organic carrier.

This invention provides cellulose ester interpolymers, and methods of oxidizing cellulose interpolymers and cellulose ester interpolymers. The invention also provides routes to access carboxylated cellulose ester derivatives with high acid numbers wherein the carboxyl group is attached directly to the cellulose backbone by a carbon-carbon bond. Through functionalization of an intermediate aldehyde, the corresponding cationic or zwitterionic cellulose ester derivatives can also be accessed. The interpolymers of the present invention have a number of end-use applications, for example, as binder resins in various types of coating compositions and as drug delivery agents.