A poly(phenylene sulfide) fiber changes little in fiber structure and has excellent long-term heat resistance. Namely, the poly(phenylene sulfide) fiber has a degree of crystallization of 45.0% or higher, a content of movable amorphous components of 15.0% or less, and a weight-average molecular weight of 300,000 or less.

The present invention relates to sulfur based polymers and a process of making sulfur based polymers. The invention also relates to sorbents comprising the sulfur-based polymers. The invention also relates to the use of such polymers and sorbents in metal remediation or extraction. The invention also relates to methods of removing heavy metals from fluids.

The present invention relates to sulfur based polymers and a process of making sulfur based polymers. The invention also relates to sorbents comprising the sulfur-based polymers. The invention also relates to the use of such polymers and sorbents in metal remediation or extraction. The invention also relates to methods of removing heavy metals from fluids.

Process for the preparation of a polysulfide comprising the step of reacting in the absence of a dihaloalkane a bis(2-dihaloalkyl)formal in the presence of (i) a pre-polymer (I) according to structure (I)

X(R2O)nCH2O(R1O)mCH2(OR2)pX(I),

wherein R1 and R2 can be the same or different and are selected from alkane chains containing 2-10 carbon atoms, X is a halogen atom, and n, m, and p are integers that can be the same or different and have a value in the range 1-6, with either (i) sodium polysulfide or (ii) a combination of sodium hydrosulfide and sulfur.

Process for the preparation of a polysulfide comprising the step of reacting in the absence of a dihaloalkane a bis(2-dihaloalkyl)formal in the presence of (i) a pre-polymer (I) according to structure (I)

X(R2O)nCH2O(R1O)mCH2(OR2)pX(I),

wherein R1 and R2 can be the same or different and are selected from alkane chains containing 2-10 carbon atoms, X is a halogen atom, and n, m, and p are integers that can be the same or different and have a value in the range 1-6, with either (i) sodium polysulfide or (ii) a combination of sodium hydrosulfide and sulfur.

Copolymerization of elemental sulfur with functional comonomers afford sulfur copolymers having a high molecular weight and high sulfur content. Nucleophilic activators initiate sulfur polymerizations at relative lower temperatures and in solutions, which enable the use of a wider range of comonomers, such as vinylics, styrenics, and non-homopolymerizing comonomers. Nucleophilic activators promote ring-opening reactions to generate linear polysulfide intermediates that copolymerize with comonomers. Dynamic sulfur-sulfur bonds enable re-processing or melt processing of the sulfur polymer. Chalcogenide-based copolymers have a refractive index of about 1.7-2.6 at a wavelength in a range of about 5000 nm-8.Math..Math.. The sulfur copolymer can be a thermoplastic or a thermoset for use in elastomers, resins, lubricants, coatings, antioxidants, cathode materials for electrochemical cells, dental adhesives/restorations, and polymeric articles such as polymeric films and free-standing substrates. Optical substrates are constructed from the chalcogenide copolymer and are substantially transparent in the visible and infrared spectrum.

Sulfur copolymers having high sulfur content for use as raw materials in 3D printing. The sulfur copolymers are prepared by melting and copolymerizing one or more comonomers with cyclic selenium sulfide, elemental sulfur, elemental selenium, or a combination thereof. Optical substrates, such as films and lenses, are constructed from the sulfur copolymer via 3D printing and are substantially transparent in the visible and infrared spectrum. The optical substrates can have refractive indices of about 1.75-2.6 at a wavelength in a range of about 500 nm to about 8 m.

Sulfur copolymers having high sulfur content for use as raw materials in 3D printing. The sulfur copolymers are prepared by melting and copolymerizing one or more comonomers with cyclic selenium sulfide, elemental sulfur, elemental selenium, or a combination thereof. Optical substrates, such as films and lenses, are constructed from the sulfur copolymer via 3D printing and are substantially transparent in the visible and infrared spectrum. The optical substrates can have refractive indices of about 1.75-2.6 at a wavelength in a range of about 500 nm to about 8 m.

Sulfur copolymers and methods of synthesizing said sulfur copolymers are described herein. Elemental sulfur is melted to form liquid sulfur monomers having reactive sulfur groups. Epoxy-functionalized styrenic comonomers having an epoxide moiety and a vinylic moiety are added to the liquid sulfur monomers. The reactive sulfur groups of the liquid sulfur monomers copolymerize with the epoxide or vinylic moiety of the epoxy-functionalized styrenic comonomers to form a crosslinked network of the sulfur copolymer.

Sulfur copolymers and methods of synthesizing said sulfur copolymers are described herein. Elemental sulfur is melted to form liquid sulfur monomers having reactive sulfur groups. Epoxy-functionalized styrenic comonomers having an epoxide moiety and a vinylic moiety are added to the liquid sulfur monomers. The reactive sulfur groups of the liquid sulfur monomers copolymerize with the epoxide or vinylic moiety of the epoxy-functionalized styrenic comonomers to form a crosslinked network of the sulfur copolymer.