摘要:
An unsaturated elastomeric AB block copolymer, comprising:(i) 45-85 wt. % 1,3-butadiene,(ii) 5-40 wt. % isoprene, and(iii) up to 30 wt. % styrene,wherein said AB block copolymer comprising:40-80 wt. % of a block A, said block A comprising butadiene monomer units and having a content of uniformly distributed vinyl groups of 8-60 wt. %, and60-20 wt. % of a block B, said block B comprising 0-60 wt. % 1,3-butadiene, at least 10 wt. % isoprene and up to 45 wt. % styrene monomer units, wherein the butadiene and isoprene monomer units have a vinyl group content of 75-90 wt. %.
摘要:
The invention concerns carbohydrate fatty acid esters with improved color and free-flow properties and a one-step process for preparing them. To prepare the products, carbohydrates are esterified with fatty acids in the presence of polyether polyols.
摘要:
Polyisoprenes having a high content of 1,2- and 3,4-structural units, a process for their preparation, and their use.The previous processes for the preparation of polyisoprene having a high content of 1,2- and 3,4-structural units were still unsatisfactory in terms of the cocatalyst employed.The use of ethylene glycol dialkyl ethers of the formulaR.sub.1 --O--CH.sub.2 --CH.sub.2 --O--R.sub.2in which R.sub.1 and R.sub.2 are alkyl groups having different numbers of C atoms, from the group consisting of methyl, ethyl, n- and isopropyl and n-, iso-, sec.- and tert.-butyl, has, in particular, the advantage that the "living polymers" formed during the anionic polymerization are not damaged.The production of tires and damping elements using these polyisoprenes.
摘要:
13-oxabicyclo[10.3.0]pentadecane, a valuable ambergris fragrance, is prepared by reacting cyclododecanone with cyanoacetic acid in the presence of a Knoevenagel catalyst to form cyclododecenylacetonitrile, the nitrile is hydrolyzed to cyclododecenylacetic acid, and the acid is cyclized to the lactone, and the lactone is reduced to the corresponding diol which is cyclized to 13-oxabicyclo[10.3.0]pentadecane.
摘要:
A microwax for use in printing ink and varnish systems is obtained by first spraying a wax melt to obtain a powder comprising substantially spherical particles, and subsequently grinding the powder of spherical particles.
摘要:
A high molecular weight aromatic polyamide molding composition prepared by the polycondensation reaction of:(A) An aromatic diamine of the formula:H.sub.2 N--AR'--O--Ar"--CO--Ar"--O--Ar'--NH.sub.2wherein Ar' and Ar" are meta- or para-phenylene, and wherein up to 70 mole % of said aromatic diamine can be replaced by a second aromatic diamine having the formula:H.sub.2 N--Ar--((Z).sub.q --Ar).sub.r --NH.sub.2wherein Ar is meta- or para-phenylene, Z is identical or different radicals selected from the group consisting of --O--, --S--, --SO.sub.2 --, --CO--, and --C(CH.sub.3).sub.2 --, q is 0 or 1, and r is 0, 1 or 2, with(B) An aromatic dicarboxylic acid selected from the group consisting of:(i) isophthalic acid, wherein up to 60 mole % of said isophthalic acid may be replaced with terephthalic acid, wherein said isophthalic acid and said terephthalic acid may be ring substituted with one or more substituents selected from the group consisting of C.sub.1-6 alkyl, phenyl, alkyl or aryl substituted phenyl, C.sub.1-6 alkoxy, phenoxy, alkyl or aryl substituted phenoxy and halogen substituents;(ii) a dicarboxylic acid of the formula ##STR1## (iii) a dicarboxylic acid of the formula:HO.sub.2 C--Ar--(A--Ar).sub.p --CO.sub.2 Hwherein Ar is meta- or para-phenylene, A is --O--, --S--, --SO.sub.2 --, or --CO--, and p is 0 or 1; and mixtures thereof.
摘要:
Impact-resistant polyamide molding compound consisting of a mixture ofA. 60 to 98% by weight of a polyamide andB. 2 to 40% by weight of a polyalkenamer, wherein the mixture is treated at elevated temperatures with 0.05 to 5% by weight of the sum of components A and B of an organic radical former are provided as well as processes for making them.
摘要:
A process for the preparation of trialkanolamine di(fatty acid) esters in which a trialkanolamine is reacted with a fatty acid in the presence of small amounts of a fatty acid ester.The trialkanolamine fatty acid diesters obtained can be converted into the quaternary ammonium salt by means of standard quaternizing agents, and the resulting products can be employed as fabric conditioners.
摘要:
For the non-clogging, fractional desublimation of vapor-phase solids contained in a gas-vapor mixture, the gas-vapor mixture, exiting at high velocity from a nozzle, is mixed with a cooling gas, likewise exiting at high velocity from another nozzle. The gas-vapor mixture and the cooling gas flow toward each other, the axes of the two gaseous streams being a straight line. Fractional desublimation of the solids is attained by adjustment of flows leading to the regulation of the temperature and residence time of the cooled gas-vapor mixture. This desublimation system is capable of degrees of efficiency and solids purities higher than 99%.
摘要:
A process produces a free flowing, silicic-acid-filled, powdered elastomer wherein the silicic acid employed has the properties set out below:(a) SiO.sub.2 content: about 82-91.5% by weight;(b) metallic oxides: about 0.5-3% by weight;(c) loss on ignition (DIN 55 921/2--measured at 100.degree. C.): about 8-15% by weight;(d) moisture (DIN 53 198--measured at 105.degree. C.): about 2-10% by weight;(e) surface area of the primary particles according to BET: about 40-250 m.sup.2 /g;(f) dibutyl phthalate absorption (ASTM D 2414-79) based on measured weight: about 170-290%.(g) linear average of numerical distribution of secondary particles: about 10-2,000 nm;(h) linear average of volume distribution of secondary particles: about 3-30 um;(i) proportion of secondary particles with a diameter of less than 1 um: about 0.01-5% by weightwherein the percentages of parameters (a) to (c), added up together, must yield 100% by weight.