摘要:
Rubber-reinforced vinyl aromatic polymers having a strictly bimodal morphology, comprising from 55 to 90% by weight of a rigid polymeric matrix and from 10 to 45% by weight of a rubbery phase dispersed inside said rigid polymeric matrix, in the form of grafted and occluded particles and wherein said rubber particles consist of from 60 to 99% by weight of particles with a capsule or “core-shell” morphology and from 1 to 40% by weight of particles with a “salami” morphology, said percentages being measured on the basis of the weight of the rubber particles only.
摘要:
Butadiene is anionically polymerized (or block copolimerized with styrene) in a low-boiling non-polar solvent in presence of rganolithiura compounds. At the end of the polymerization, the non-polar solvent is switched with styrene and the new solution is stored in tanks in relation to the type of polybutadiene (or its block copolymer with styrene) obtained. The polybutadiene solution (and/or its block copolymer with styrene) with the desired set of properties is then fed to a production plant of high impact vinyl aromatic (co) polymers.
摘要:
A process for the continuous production of granules based on thermoplastic polymers includes at least one expandable agent and, optionally, other polymers or additives, among which inorganic pigments insoluble in the polymeric matrix, wherein a first main stream is prepared, in the molten state, and a second stream in the molten state, which englobes the additives and which is added to the first stream. The mixture is extruded through a die which is cooled by means of water jets from nozzles positioned behind the cutting blades.
摘要:
Compositions of expandable vinylaromatic polymers which contain a polymer, of at least one vinylaromatic monomer, having an average molecular weight Mw ranging from 50,000 to 170,000, which comprise: a) 0-50% by weight of a copolymer obtained by polymerizing one or more vinylaromatic monomers and 0.1-15% by weight of an α-alkylstyrene; b) 0-10% by weight of a compatible polymer having a crystallinity lower than 10% and a glass transition temperature (Tg) higher than 100° C., the remaining percentage consisting of the vinylaromatic polymer; c) 2-10% by weight, calculated with respect to the total, of an expanding agent; with the proviso that at least one of (a) or (b) is present in the polymeric mixture.
摘要:
Expandable vinylaromatic polymers which comprise: a) a matrix obtained by polymerizing 50-100% by weight of one or more vinylaromatic monomers and 0.50% by weight of a copolymerizable monomer; b) 1-10% by weight, calculated with respect to the polymer (a), of an expanding agent englobed in the polymeric matrix; c) 0.05-25% by weight, calculated with respect to the polymer (a), of an inorganic filler homogeneously distributed in the polymeric matrix with a substantially spherical granulometry, an average diameter ranging from 0.01 to 100 μm, a refraction index higher than 1.6 and a white index, as defined in “Colour Index” (third edition published by the Society of Dyers and Colourists, 1982), equal to or lower than 22.
摘要翻译:可膨胀的乙烯基芳族聚合物,其包含:a)通过聚合50-100重量%的一种或多种乙烯基芳族单体和0.50重量%的可共聚单体获得的基体; b)相对于聚合物(a)计算的占聚合物基质中的发泡剂的1-10重量% c)相对于聚合物(a)计算的0.05-25重量%的均匀分布在聚合物基质中的无机填料,其基本上为球形粒度,平均直径为0.01至100μm,折射率高于 1.6和白色指数,如“颜色指数”(由Dyers and Colourists,1982年出版的第三版)定义的等于或低于22。
摘要:
A process for the production of nano-scaled graphene platelets which comprises: a) putting a graphite material in contact with molecular or atomic oxygen or a substance capable of releasing molecular or atomic oxygen, obtaining a precursor consisting of graphite material functionalized with oxygen groups (FOG), characterized by a carbon/oxygen molar ratio higher than 8:1 b) subsequently, reducing (chemically or physically) said FOG precursor obtaining nano-scaled graphene platelets characterized by a carbon/oxygen molar ratio higher than 20:1.
摘要:
Process for the alkylation of aromatic hydrocarbons by means of aliphatic alcohols containing from 1 to 8 carbon atoms, which comprises feeding the hydrocarbon and alcohol to the head of a fixed-bed reactor, operating with “trickle flow” regime, containing at least one layer of a catalyst comprising a zeolite selected from medium-pore zeolites and large-pore zeolites.
摘要:
Process for the alkylation of aromatic hydrocarbons by means of olefins containing from 2 to 8 carbon atoms, which comprises feeding the hydrocarbon, olefin, and possibly water, to the head of a fixed-bed reactor, operating with a “trickle flow” regime, containing at least one layer of a catalyst comprising a medium-or large-pore zeolite.
摘要:
Butadiene is anionically polymerized (or block copolimerized with styrene) in a low-boiling non-polar solvent in presence of rganolithiura compounds. At the end of the polymerization, the non-polar solvent is switched with styrene and the new solution is stored in tanks in relation to the type of polybutadiene (or its block copolymer with styrene) obtained. The polybutadiene solution (and/or its block copolymer with styrene) with the desired set of properties is then fed to a production plant of high impact vinyl aromatic (co)polymers.
摘要:
Nanocomposite compositions based on expandable thermoplastic polymers which comprise: a) a polymeric matrix produced by the polymerization of a base comprising one or more polymerizable monomers; b) 1-10% by weight, calculated with respect to the polymer (a), of an expanding agent englobed in the polymeric matrix; c) 0.004-15% by weight, calculated with respect to the polymer (a), of an athermanous filler comprising nano-scaled graphene plates with a thickness (orthogonal to the graphene sheet) not greater than 150 nm, an average dimension (length, width, or diameter) not greater than 10 micrometers and a surface area>50 m2/g.