摘要:
Novel carbon molecular sieve (CMS) compositions comprising carbonized vinylidene chloride copolymer having micropores with an average micropore size ranging from 3.0 to 5.0. These materials offer capability in separations of gas mixtures including, for example, propane/propylene; nitrogen/methane; and ethane/ethylene. Such may be prepared by a process wherein vinylidene chloride copolymer beads, melt extruded film or fiber are pretreated to form a precursor that is finally carbonized at high temperature. Preselection or knowledge of precursor crystallinity and attained maximum pyrolysis temperature enables preselection or knowledge of a average micropore size, according to the equation ?=6.09+(0.0275×C)−(0.00233×T), wherein ? is the average micropore size in Angstroms, C is the crystallinity percentage and T is the attained maximum pyrolysis temperature in degrees Celsius, provided that crystallinity percentage ranges from 25 to 75 and temperature in degrees Celsius ranges from 800 to 1700. The beads, fibers or film may be ground, post-pyrolysis, and combined with a non-coating binder to form extruded pellets, or alternatively the fibers may be woven, either before or after pre-treatment, to form a woven fiber sheet which is thereafter pyrolyzed to form a woven fiber adsorbent.
摘要:
A polymer blend including a vinylidene chloride interpolymer; an ethylene-acrylate interpolymer; and optionally one or more additives selected from the group consisting of stabilizers, plasticizers, and processing aids is provided. Also provided is an extruded film and a packaging or container which includes the film.
摘要:
Disclosed herein is a barrier film comprising at least two substrates each comprising a first surface and a second surface; where the first surface and the second surface are opposedly disposed to each other; the second surfaces of each substrates being in direct contact with each other; where the second surfaces do not contact a barrier coating; and a barrier coating comprising alternating layers of cationic material and anionic material; where the barrier coating is adhesively bonded with the first surfaces of each substrate.
摘要:
The present invention relates generally to vinylidene chloride polymer compositions. In one embodiment, a vinylidene chloride polymer composition comprises (a) a vinylidene chloride polymer formed from a monomer mixture comprising from 60 to 99 weight percent vinylidene chloride monomer and from 40 to 1 weight percent of a monoethylenically unsaturated monomer copolymerizable therewith; (b) 0.3 to 5 weight percent of an acrylic polymer based on the total weight of the polymer composition; and (c) 0.2 to 7 weight percent of at least one additive comprising (i) at least one wax in an amount of from 0.01 to 2 weight percent based on the total weight of the polymer composition, (ii) at least one polyethylene having a density greater than 0.940 g/cm3 in an amount of from 0.1 to 5 weight percent based on the total weight of the polymer composition, or combinations thereof.
摘要:
A carbonized PVDC copolymer useful for the separation of an olefin from its corresponding paraffin may be made by heating a polyvinylidene chloride copolymer film or hollow fiber having a thickness of 1 micrometer to 20 micrometers to a pretreatment temperature of 100° C. to 180° C. to form a pretreated polyvinylidene chloride copolymer film and then heating the pretreated polyvinylidene chloride copolymer film to a maximum pyrolysis temperature from 350° C. to 750° C. A process for separating an olefin from its corresponding paraffin in a gas mixture is comprised of flowing the gas mixture through the aforementioned carbonized polyvinylidene chloride (PVDC) copolymer to produce a permeate first stream having an increased concentration of the olefin and a second retentate stream having an increased concentration of its corresponding paraffin.
摘要:
A process for separating hydrogen from a gas mixture having hydrogen and a larger gas molecule is comprised of flowing the gas mixture through a carbonized polyvinylidene chloride (PVDC) copolymer membrane having a hydrogen permeance in combination with a hydrogen/methane selectivity, wherein the combination of hydrogen permeance and hydrogen/methane selectivity is (i) at least 30 GPU hydrogen permeance and at least 200 hydrogen/methane selectivity or (ii) at least 10 GPU hydrogen permeance and at least 700 hydrogen/methane selectivity. The carbonized PVDC copolymer may be made by heating and restraining a polyvinylidene chloride copolymer film or hollow fiber having a thickness of 1 micrometer to 250 micrometers to a pretreatment temperature of 100° C. to 180° C. to form a pretreated polyvinylidene chloride copolymer film and then heating and restraining the pretreated polyvinylidene chloride copolymer film to a maximum pyrolysis temperature from 350° C. to 750° C.
摘要:
Disclosed is a process to produce an improved formulated vinylidene chloride polymer comprising a solid inorganic additive and producing improved vinylidene chloride polymer film products. The process includes adding the inorganic solid additive (such as magnesium hydroxide and/or other inorganic acid scavenger) in a dispersion of a liquid, such as a liquid plasticizer or stabilizer to improve distribution through the polymer and reduction of relatively large sized particles or agglomerates in the polymer and film.
摘要:
A process to prepare a vinylidene chloride heteropolymer comprising copolymerizing vinylidene chloride with at least one comonomer selected from the group consisting of alkyl acrylates, non-vinylidene chloride vinyl monomers and combinations thereof in the presence of an indicator, wherein the indicator is soluble in vinylidene chloride, the at least one comonomer, or a mixture of the vinylidene chloride and the at least one comonomer is provided.
摘要:
Disclosed herein is a barrier film comprising a substrate comprising a first surface and a second surface; where the first surface and the second surface are opposedly disposed to each other; and a barrier coating comprising alternating layers of cationic material and anionic material; where the barrier coating is reactively bonded with at least the first surface of the substrate. Disclosed herein too is a method comprising disposing upon a substrate a barrier coating comprising alternating layers of cationic material and anionic material; where the barrier coating is reactively bonded with at least one surface of the substrate.
摘要:
The present disclosure is directed to a composition comprising (a) a vinylidene chloride/methyl acrylate interpolymer having greater than 6 wt % methyl acrylate mer units in the interpolymer, (b) greater than 6 wt % of an epoxy plasticizer; and (c) less than 4 wt % of an acrylate polymer. The composition exhibits a crystallization time greater than 25 minutes to crystallization at 35° C. Films made from the present composition show improved processability and find advantageous application as permeable barrier film for food packaging, for specialty food packaging, and for gassy cheese.