Patent classifications
C08J11/14
METHOD FOR OBTAINING SUPERABSORBENT POLYMERS VIA ALKALINE HYDROLYSIS WITH PRESSURIZED WATER VAPOUR, USING POLYACRYLONITRILE AND ACRYLIC FIBRES AND FABRICS
A method for producing superabsorbent polymers from polyacrylonitrile (PAN) virgin or recycled from acrylic fibre manufacturing waste and discarded fabrics subjecting the PAN to alkaline hydrolysis with pressurized water vapour of up to 5 kgf/cm.sup.2 and a PAN:OH.sup.− molar ratio of 1:0.5 to 0.95, to obtain a cross-linked poly(acrylic acid-co-acrylamide) salt without using mechanical agitation, graphitizing agents with starch or cross-linking agents, and without precipitating the superabsorbent polymer obtained from the reaction medium with solvents or through pH adjustment with acids, the polymer obtained with recycled PAN leaves the autoclave already having a moisture content of 20% to 35% and a swelling capacity of >150 g H.sub.2O/g.
METHOD FOR OBTAINING SUPERABSORBENT POLYMERS VIA ALKALINE HYDROLYSIS WITH PRESSURIZED WATER VAPOUR, USING POLYACRYLONITRILE AND ACRYLIC FIBRES AND FABRICS
A method for producing superabsorbent polymers from polyacrylonitrile (PAN) virgin or recycled from acrylic fibre manufacturing waste and discarded fabrics subjecting the PAN to alkaline hydrolysis with pressurized water vapour of up to 5 kgf/cm.sup.2 and a PAN:OH.sup.− molar ratio of 1:0.5 to 0.95, to obtain a cross-linked poly(acrylic acid-co-acrylamide) salt without using mechanical agitation, graphitizing agents with starch or cross-linking agents, and without precipitating the superabsorbent polymer obtained from the reaction medium with solvents or through pH adjustment with acids, the polymer obtained with recycled PAN leaves the autoclave already having a moisture content of 20% to 35% and a swelling capacity of >150 g H.sub.2O/g.
Recyclable PET film
The present invention relates to a multilayer, coextruded polyester film that includes at least one outer layer (A) and a base layer (B), in which the at least one outer layer (A) includes to an extent of at least 60 wt % of a copolyester that includes units derived from dicarboxylic acids and diols, in which the units derived from dicarboxylic acids include at least 65 mol % of units derived from terephthalic acid and at least 5 mol % of units derived from 5-sulfo-isophthalic acid and the units derived from diols include at least 90 mol % of units derived from ethylene glycol.
The present invention further relates to a process for producing the film according to the invention, to the use thereof and to a process for recycling the polyester film according to the invention.
Recycling of cellulosic textiles
A method for recycling textiles comprising cellulose with the following steps of: optionally disintegrating the textile, Swelling the cellulose, under reducing conditions, wherein at least one reducing agent is present at least during a part of the swelling, and then performing at least one of the following two bleaching steps in any order: i) bleaching the material with oxygen at alkaline conditions with a pH in the range 9-13.5, and ii) bleaching the material with ozone at acid conditions below pH 6. An advantage is that the yield is improved at the same time as excellent decolourization is achieved. If the recycled material is used in viscose manufacture, the risk of clogging nozzles and so on is reduced.
METHODS FOR DEPOLYMERIZING POLYESTERS
A method for depolymerizing a polyester may comprise heating a polyester at a temperature and for a period of time in the presence of a supported metal-dioxo catalyst, optionally, in the presence of H.sub.2, to induce hydrogenolysis of ester groups in the polyester and provide monomers of the polyester.
Recycling of superabsorbent polymer with an extensional flow device
Poly(acrylic acid)-based superabsorbent polymer (SAP) in a feed stream is converted into poly(acrylic acid) (PAA) in an extensional flow device. The total energy used to degrade the SAP into PAA is less than about 50 MJ/kg SAP.
MEANS FOR CONVERTING POST CONSUMER CELLULOSIC TEXTILE WASTE INTO NANOCELLULOSE
The present invention discloses means, and systems utilizable in a method for converting post-consumer cellulose-containing (e.g., cotton) textile waste (ctPCR) to nanocellulose, derivatives, and products thereof, comprising steps as follows: grinding said ctPCT; suspending the ground ctPCR in basic pH hydrophilic slurry; and exposing the same to ozone gas.
METHOD OF DEPOLYMERIZING A POLYESTER IN A WASTE MATERIAL
A method of depolymerizing a polyester in a waste material is disclosed. The method comprises: supplying the waste material comprising the polyester to a depolymerization vessel; depolymerizing the polyester to form a depolymerized mixture comprising a regenerated diol, a regenerated diacid, and a catalyst; isolating the regenerated diacid and the catalyst from the regenerated diol to form a regenerated composition including the regenerated acid and the catalyst; and separating the regenerated composition from the regenerated diol. In addition, a regenerated composition formed from depolymerization of a waste material is disclosed wherein the regenerated composition comprises a regenerated diacid and a catalyst and wherein the catalyst is present in an amount of from 5 ppm to 300 ppm.
METHOD OF DEPOLYMERIZING A POLYESTER IN A WASTE MATERIAL
A method of depolymerizing a polyester in a waste material is disclosed. The method comprises: supplying the waste material comprising the polyester to a depolymerization vessel; depolymerizing the polyester to form a depolymerized mixture comprising a regenerated diol, a regenerated diacid, and a catalyst; isolating the regenerated diacid and the catalyst from the regenerated diol to form a regenerated composition including the regenerated acid and the catalyst; and separating the regenerated composition from the regenerated diol. In addition, a regenerated composition formed from depolymerization of a waste material is disclosed wherein the regenerated composition comprises a regenerated diacid and a catalyst and wherein the catalyst is present in an amount of from 5 ppm to 300 ppm.
A PROCESS FOR RECYCLING A POLYURETHANE MATERIAL
A process for recycling a polyurethane material wherein the polyurethane material comprises a moiety that is capable of undergoing decomposition through acidolysis, the process comprising: contacting the polyurethane material with an acid solution and allowing at least a portion of the polyurethane material to decompose into a recovered raw material composition comprising a degradation compound; and introducing an acetoacetylated polyol into the recovered raw material composition and reacting the acetoacetylated polyol with the degradation compound to form a polyol compound.