摘要:
The present invention provides thermoplastically workable and completely biodegradable moulding compositions, a process for the preparation thereof and the use thereof as biodegradable materials for the production of, for example, injection-moulded parts, films, fibres or coatings.
摘要:
Thermoplastic and compostable cellulose ether esters with 2-hydroxycarboxylic acids as acid components and mixed esters which, in addition to 2-hydroxycarboxylic acid groups, have further mono-, dicarboxylic acid or carbamate groups.
摘要:
The present invention relates to novel thermoplastic materials based on polysaccharide ethers which are simultaneously substituted by carboxylic acid ester groups and carbamate groups, together with mixtures of such derivatives with low molecular weight aliphatic urea derivatives.
摘要:
The present invention relates to evenly substituted polysaccharide derivatives having the general structure: polysaccharide—O—R wherein polysaccharide—O represents a substituted or unsubstituted polysaccharide unit and R is a substituent of a polysaccharide-OH group having either the structure R=—A—B— or the structure R=—B—, wherein A is a linear polyether chain having the following structure: A=(—D—O—)n wherein D denotes a linear aliphatic branched or unbranched chain having 2 to 12 C atoms, O represents an oxygen atom and n is a number equal to or greater than 1, and B represents a substituted carbamic acid having the structure wherein E denotes a linear or branched aliphatic chain having 1 to 18 C atoms.
摘要:
The invention relates to a completely biodegradable hydrogel comprising polyester polyurethane polyurea containing urea groups as well as polysaccharides and/or their derivatives, the hydrogel containing plant material capable of dividing. The invention also relates to a process for the embedding of the biological material and the fabrication and shaping of the hydrogels from aqueous solutions. The hydrogels according to the invention may be used as coating material for embedding biological material capable of dividing, especially plant material, preferably plant cells, protoplasts, plant tissues and plant organs, as well as zygotic or somatic plant embryos, under sterile conditions for the purpose of protecting the material during storage, transport and handling. The hydrogels according to the invention may also contain further additives, for example, plant protection agents or nutrients. The embedded biological plant material according to the invention may be used as artificial seed.
摘要:
In a process for purifying crude pyrrolidine to give a pyrrolidine composition comprising more than 99% (m/m) of pyrrolidine and less than 0.3% (m/m) of water, crude pyrrolidine comprising from 40 to 98% (m/m) of pyrrolidine and having a water content of more than 2% (m/m) is subjected to continuous distillation at a pressure at the top of less than 950 hPa in a column having a stripping section and a rectifying section.
摘要:
The invention concerns novel plant-treatment agents comprising: at least one thermoplastically processable biodegradable polyester amide, optionally in a mixture with one or a plurality of further thermoplastically processable, biodegradable polymer components; at least one agrochemical substance; and optionally additives. The invention further concerns a process for preparing these agents, and their use in the application of agrochemical substances.
摘要:
A process for preparing pyrroles of the formula I: ##STR1## where R.sub.1, R.sup.2, R.sup.3 and R.sup.4 are identical or different and are hydrogen atoms, alkyl groups having from 1 to 12 carbon atoms or cycloalkyl groups having from 3 to 12 carbon atoms, by dehydrogenation of pyrrolidines of the formula II: ##STR2## where R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are as defined above, in the presence of a supported noble metal catalyst is described. In this process, the dehydrogenation is carried out at from 150 to 300.degree. C. and pressures of from 0.01 to 50 bar and the noble metal catalyst comprises from 30 to 100% by weight of:a) palladium on an oxide of a rare earth or an oxide of an element of the 4.sup.th group (transition group IV) of the Periodic Table, orb) a platinum/palladium mixture on aluminum oxide, an oxide of a rare earth or an oxide of an element of the 4.sup.th groupand from 0 to 70% by weight of alkali metal oxide or alkaline earth metal oxide.
摘要:
Optically active amines are racemized by reaction of the optically active amine in the gas phase at elevated temperature in the presence of hydrogen and a hydrogenation or dehydrogenation catalyst.
摘要:
In a process for racemizing optically active amines by reacting the optically active amine in the presence of hydrogen and a hydrogenation or dehydrogenation catalyst at elevated temperature, the reaction is carried out in liquid phase and the catalyst comprises the catalytically active constituents copper, silver, iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and/or platinum and a support material selected from the group consisting of aluminum oxide, zirconium dioxide, titanium dioxide, carbon and/or oxygen compounds of silicon.