The disclosure relates to a dipping former, to a process for producing the dipping former and to the use of the dipping former in a latex dipping process. The dipping comprises (i) a molded core part, and (ii) a dipping former shell having a surface in one piece. The dipping former is obtainable by a molding process comprising the following steps: —providing a first cavity and a second cavity; —injection molding or blow molding a first material into the first cavity thereby forming a molded core; —transferring the molded core form the first cavity into the second cavity; and —injection molding of a second material into the second cavity thereby overmolding the molded core, or at least a part thereof, with the second material.

Dipped formed latex articles with improved properties are formed from branched block copolymers, derived from alkenyl aromatic hydrocarbon—1,3-diene monomer system, and branched polyisoprene homopolymers, derived from isoprene. The polymers are obtained by polymerization in the presence of an anionic initiator; at a temperature from 0° C. to 100° C.; followed by coupling with a multifunctional coupling agent of formula (R.sup.1O).sub.3Si—Y—Si(OR.sup.2).sub.3, wherein R.sub.1 and R.sub.2 are independently C.sub.1-C.sub.6 alkyl groups; and Y is a C.sub.2-C.sub.8 alkylene group. The polymers are obtained as rubber cements having high solids content and low zero shear viscosities. The rubber cements are valuable for making latices and latex articles such as dipped goods, e.g., condoms, gloves, etc., with improved properties.

One embodiment of the present invention relates to a chloroprene copolymer latex, a method for producing a chloroprene copolymer latex, a chloroprene copolymer latex composition, and a molded article or dipped product of a chloroprene copolymer rubber. The chloroprene copolymer latex is a latex of a chloroprene copolymer including monomer units derived from 2-chloro-1,3-butadiene (chloroprene) and monomer units derived from 2-methyl-1,3-butadiene, wherein the tetrahydrofuran insoluble content in the chloroprene copolymer is 20% by mass or less, and the proportion of the monomer units derived from 2-methyl-1,3-butadiene is 10 to 27 mol % in the chloroprene copolymer.

A latex composition for dip molding includes a carboxylic acid-modified nitrile-based copolymer latex having pKa of 9.5 to 10.2 and satisfying General Formulas 1 and 2.

0.85≤P≤1.0, P=CV.sub.D/CV.sub.0  [General Formula 1]

5≤M≤20, M=m.sub.1×m.sub.2  [General Formula 2] wherein CV.sub.0 represents a capillary viscosity which is measured in a swollen in a methyl ethyl ketone solvent, CV.sub.D represents a capillary viscosity in a deswollen state, m.sub.1 represents an insolubility of a dried film in the methyl ethyl ketone solvent, and m.sub.2 represents a swelling index of the dried film in the methyl ethyl ketone solvent, wherein a carboxylic acid-modified nitrile-based copolymer of carboxylic acid-modified nitrile-based copolymer latex includes: a conjugated diene-based monomer-derived unit, an ethylenic unsaturated nitrile-based monomer-derived unit, and an ethylenic unsaturated acid monomer-derived unit. A molded article having a layer derived from the latex composition is also provided.

The present technology provides a carboxylic acid-modified nitrile-based copolymer latex including a carboxylic acid-modified nitrile-based copolymer including a conjugated diene-based monomer-derived unit, an ethylenic unsaturated nitrile-based monomer-derived unit, and an ethylenic unsaturated acid monomer-derived unit, wherein a pKa is 9.5 to 10.2, and the carboxylic acid-modified nitrile-based copolymer latex satisfies General Formulas 1 and 2.

An article comprises a laminate with a layer comprising a first latex composition containing a cross-linker component selected from sulfur, organic peroxide, vulcanizing activators, and vulcanizing accelerator; and a second layer comprising a second latex composition free of the cross-linker component. The laminate is formed by dipping a mold into the first latex composition then into the second latex composition forming a laminated film, then curing the laminated film by heating to a temperature between 90° C. to 140° C. Lastly, the laminated film is removed from the mold via inversion such that the second layer is inwards and the first layer is outwards.

A latex composition for dip molding includes a carboxylic acid-modified nitrile-based copolymer latex and a cholate-based emulsifier, wherein the cholate-based emulsifier is included in an amount of 0.02 to 3 parts by weight based on a solid content with respect to a solid content of 100 parts by weight of the carboxylic acid-modified nitrile-based copolymer latex. A method of preparing the latex composition for dip molding and a molded article produced using the same are also provided.

A method for producing a polymer latex includes: a preparation step of reducing the weight average molecular weight of a conjugated diene polymer (A) by 20 to 70 mass %, thereby obtaining an organic solvent solution containing a conjugated diene polymer (B) having a weight average molecular weight lower than that of the conjugated diene polymer (A); and an emulsification step of emulsifying the organic solvent solution in water in the presence of a surfactant, thereby obtaining a polymer latex.

The application discloses a glove demolding mechanism, a glove counting machine and a glove demolding method. The glove demolding mechanism includes a glove demolding unit, a first induction device and a vertical power assembly, the glove demolding unit is fixed on the vertical power assembly, and the vertical power assembly is capable of driving the glove demolding unit to move vertically, the first induction device is arranged at a position away from rear ends of the glove demolding units for a set distance, and the glove demolding unit can move upwards to the appropriate position under the bottom of gloves to clamp the gloves driving by the vertical power assembly. When the glove demolding mechanism is used to separate the gloves from hand molds, the gloves can be more ordered.

Provided among other things is an elastomeric article providing a chemical barrier, the article having a layered structure comprising a sequential laminate of: (a) a latex-based elastomeric polymeric barrier layer; (b) a non-reactive tie adhesive resin layer comprising oxo (—(C═O)—) groups; and (c) a polyamide layer; wherein the layered structure has a first side nearest the latex-based elastomeric polymeric barrier layer and a second side; wherein the layered structure is effective to provide a chemical permeation time in excess of 100 minutes pursuant to EN 16523-1:2015 for benchmark solvents of acetone, ethyl acetate and methanol, when applied to the first side, and in excess of 100 minutes for acetone when applied to the second side; and wherein the elastomeric layer is primarily not polyolefin.