The invention relates to heat treatment of polymorphic semicrystalline or crystallizable polymers to increase the content of the highest melting crystalline form. Such heat treatment results in a polymer powder that has a consistent, uniform melting range, improved flow and improved durability of the powder particle size for applications that require powder flow at elevated temperatures. In addition to improved powder properties, the articles produced from the powders also exhibit better physical properties in both appearance and in mechanical properties. Thus the invention also includes polymer powders and articles produced by the described processes.

The invention relates to heat treatment of polymorphic semicrystalline or crystallizable polymers to increase the content of the highest melting crystalline form. Such heat treatment results in a polymer powder that has a consistent, uniform melting range, improved flow and improved durability of the powder particle size for applications that require powder flow at elevated temperatures. In addition to improved powder properties, the articles produced from the powders also exhibit better physical properties in both appearance and in mechanical properties. Thus the invention also includes polymer powders and articles produced by the described processes.

The invention provides a polyetheretherketone (PEEK) composite and a method of preparing same. The PEEK composite is prepared from 55-90 parts by mass of PEEK, 5-30 parts by mass zinc aluminum (ZA) alloy, 5-15 parts by mass graphite, 0.3-1 parts by mass graphene oxide (GO) and a processing additive. The PEEK composite is prepared by the following steps: putting the ZA alloy into an aqueous solution of a quaternary ammonium salt surfactant, ultrasonically dispersing, filtering, washing and drying; dissolving the GO in deionized water, dispersing the ZA alloy in deionized water, and adding a GO solution dropwise to a ZA alloy dispersion to obtain a GO/ZA alloy complex; mixing the PEEK, the GO/ZA alloy complex, the graphite and the processing additive, and drying at 100-120° C. for 3-4 h; and mixing in a mixer, and carrying out compression molding at 380-400° C.

The invention provides a polyetheretherketone (PEEK) composite and a method of preparing same. The PEEK composite is prepared from 55-90 parts by mass of PEEK, 5-30 parts by mass zinc aluminum (ZA) alloy, 5-15 parts by mass graphite, 0.3-1 parts by mass graphene oxide (GO) and a processing additive. The PEEK composite is prepared by the following steps: putting the ZA alloy into an aqueous solution of a quaternary ammonium salt surfactant, ultrasonically dispersing, filtering, washing and drying; dissolving the GO in deionized water, dispersing the ZA alloy in deionized water, and adding a GO solution dropwise to a ZA alloy dispersion to obtain a GO/ZA alloy complex; mixing the PEEK, the GO/ZA alloy complex, the graphite and the processing additive, and drying at 100-120° C. for 3-4 h; and mixing in a mixer, and carrying out compression molding at 380-400° C.

A composite material for use as a deposition material in an additive manufacturing system comprises a polymer component, a filler component, and an extrudability component. The extrudability component is present in the composite material is an amount of from 0.05 wt % to 10 wt % based on the weight of the composite material, and can comprise polyhedral oligomeric silsesquioxane (POSS). The polymer component comprises a high temperature polymer such as an engineering polymer or a high performance polymer. The filler component comprises at least one of a conductive component and a strengthening component. In some cases, the conductive component is present in an amount such that the composite material is formed as one of an electrostatic discharge (ESD) material and an EMI/EMC shielding material. The composite material can be deposited in a liquid state on a substrate using an additive manufacturing system, to produce a three-dimensional object.

A composite material for use as a deposition material in an additive manufacturing system comprises a polymer component, a filler component, and an extrudability component. The extrudability component is present in the composite material is an amount of from 0.05 wt % to 10 wt % based on the weight of the composite material, and can comprise polyhedral oligomeric silsesquioxane (POSS). The polymer component comprises a high temperature polymer such as an engineering polymer or a high performance polymer. The filler component comprises at least one of a conductive component and a strengthening component. In some cases, the conductive component is present in an amount such that the composite material is formed as one of an electrostatic discharge (ESD) material and an EMI/EMC shielding material. The composite material can be deposited in a liquid state on a substrate using an additive manufacturing system, to produce a three-dimensional object.

The invention discloses a separator with a wide temperature range and a low heat shrinkage and a method for preparing the same. The invention belongs to the field of electrochemistry. The separator of the invention includes: an irradiation crosslinked fluoropolymer A with a melting point above 150° C. and/or a polymer B containing a benzene ring in its main chain; an ultrahigh molecular weight polyethylene having a molecular weight of 1.0×10.sup.6-10.0×10.sup.6, and a high density polyethylene having a density in the range of 0.940-0.976 g/cm.sup.3; the temperature difference between pore closing temperature and film breaking temperature of the separator is 80-90° C., preferably 85-90° C., the heat shrinkage of the separator is 2.0% or less. The separator of the invention has a high temperature difference between film breaking temperature and pore closing temperature, and a low heat shrinkage; when the separator of the invention is used in an electrochemical device, the reliability and safety of electrochemical device can be effectively improved.

The invention discloses a separator with a wide temperature range and a low heat shrinkage and a method for preparing the same. The invention belongs to the field of electrochemistry. The separator of the invention includes: an irradiation crosslinked fluoropolymer A with a melting point above 150° C. and/or a polymer B containing a benzene ring in its main chain; an ultrahigh molecular weight polyethylene having a molecular weight of 1.0×10.sup.6-10.0×10.sup.6, and a high density polyethylene having a density in the range of 0.940-0.976 g/cm.sup.3; the temperature difference between pore closing temperature and film breaking temperature of the separator is 80-90° C., preferably 85-90° C., the heat shrinkage of the separator is 2.0% or less. The separator of the invention has a high temperature difference between film breaking temperature and pore closing temperature, and a low heat shrinkage; when the separator of the invention is used in an electrochemical device, the reliability and safety of electrochemical device can be effectively improved.

The invention discloses a separator with a wide temperature range and a low heat shrinkage and a method for preparing the same. The invention belongs to the field of electrochemistry. The separator of the invention includes: an irradiation crosslinked fluoropolymer A with a melting point above 150° C. and/or a polymer B containing a benzene ring in its main chain; an ultrahigh molecular weight polyethylene having a molecular weight of 1.0×10.sup.6-10.0×10.sup.6, and a high density polyethylene having a density in the range of 0.940-0.976 g/cm.sup.3; the temperature difference between pore closing temperature and film breaking temperature of the separator is 80-90° C., preferably 85-90° C., the heat shrinkage of the separator is 2.0% or less. The separator of the invention has a high temperature difference between film breaking temperature and pore closing temperature, and a low heat shrinkage; when the separator of the invention is used in an electrochemical device, the reliability and safety of electrochemical device can be effectively improved.

A composite material for use as a deposition material in an additive manufacturing system comprises a polymer component, a filler component, and an extrudability component. The extrudability component is present in the composite material is an amount of from 0.05 wt % to 10 wt % based on the weight of the composite material, and can comprise polyhedral oligomeric silsesquioxane (POSS). The polymer component comprises a high temperature polymer such as an engineering polymer or a high performance polymer. The filler component comprises at least one of a conductive component and a strengthening component. In some cases, the conductive component is present in an amount such that the composite material is formed as one of an electrostatic discharge (ESD) material and an EMI/EMC shielding material. The composite material can be deposited in a liquid state on a substrate using an additive manufacturing system, to produce a three-dimensional object.