Electrical connector comprising furanate polyester

Abstract

The invention relates to an electrical connector comprising a housing and electrical contacts. The outer shell comprises a polymer of butanediol 2, 5-furandicarboxylate (PBF), a polymer of butanediol difuranate (PBBf), or a copolymer of butanediol 2, 5-furandicarboxylate (BF) and butanediol difuranate (BBf), a copolymer of (i) ethylene glycol 2, 5-furandicarboxylate (EF) and (ii) one or both of BF and BBf, or a copolymer of (i) ethylene glycol 2, 5-furandicarboxylate (EF) and (ii) one or both of BF and BBf, a copolymer of (i) butylene terephthalate (BT) and (ii) one or more of BF, BBf, and EF, or any combination thereof.

Description

Technical Field

[0001] The disclosed teachings relate to electrical connectors made from bio-based materials. Background Art

[0002] An electrical connector (such as an automotive connector) is an electromechanical device used to connect electrical conductors and form an electrical circuit. Most electrical connectors are classified as having genders: a male component called a plug connects to a female component called a socket. The connection can be removable (as for portable devices), require tools for assembly and removal, or serve as a permanent electrical joint between two points.

[0003] Electrical connectors often include injection molded parts. Injection molding is a manufacturing process that produces parts by injecting molten material into a mold. Injection molding can be performed with a variety of materials including metals, glass, elastomers, and most commonly thermoplastics and thermosetting polymers (e.g., thermoplastic resins).

[0004] Electrical connectors based on polybutylene terephthalate (PBT) are generally available. PBT has many attractive properties, such as high mechanical strength and toughness, high wear resistance, excellent dimensional stability and high heat distortion temperature (up to 215°C for glass fiber reinforced PBT), fast crystallization rate, high continuous use at elevated temperatures (e.g., 140°C) due to low mechanical creep, good chemical resistance, and short processing cycle times in injection molding. Due to these properties, PBT can be used in many applications, such as electrical connectors for automobiles ("car connectors") and keyboard keycaps, and therefore the global demand for PBT continues to increase. PBT can be synthesized in a two-stage process by melt polycondensation. First, bis(4-hydroxybutyl) terephthalate (BHBT) is formed by the transesterification reaction of dimethyl terephthalate (DMT) with 1,4-butanediol (BD). PBT is then formed from BHBT in the polycondensation stage while eliminating BD. Other synthetic routes include polymerization after ring opening or enzymatic methods.

[0005] Concerns about climate change due to global warming from greenhouse gas (GHG) emissions are increasing legislative and social pressure on manufacturers and consumers to reduce carbon emissions. Thus, manufacturers and consumers are being urged to reduce the use of products derived from petrochemical materials. In addition, manufacturers will need to reduce the use and eventually replace materials derived from fossil fuels that produce new carbon emissions with materials derived from biomass (i.e., renewable carbon) in the near future.

[0006] DMT used to synthesize PBT is derived from petrochemical raw materials, so the use of PBT leads to a positive carbon footprint and should therefore be replaced by bio-based polyesters with similar chemical and physical properties.

[0007] There is a need for an injection moldable polymer derived substantially from biomass that has substantially similar properties to fossil fuel derived PBT such that it can serve as a replacement material for PBT in electrical connector applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] One or more embodiments of the present disclosure are illustrated by way of example and not limitation in the figures of the accompanying drawings in which like reference numerals refer to similar elements.

[0009] Figure 1 A perspective view of an electrical housing of an electrical connector is shown.

[0010] Figure 2A A perspective view showing the construction of an electrical connector.

[0011] Figure 2B Shows Figure 2A A cross-sectional view of the structure of an electrical connector.

[0012] Figure 3 A molding machine for performing injection molding is shown.

[0013] Figure 4 is a flow chart illustrating a process for manufacturing a housing for an electrical connector. DETAILED DESCRIPTION

[0014] abbreviation

[0015] BF: butylene 2,5-furandicarboxylate.

[0016] BBf: butanediol bisfuranate.

[0017] EF: Ethylene 2,5-furandicarboxylate.

[0018] BT: Butylene terephthalate.

[0019] PBT: Polybutylene terephthalate, also known as the polymer of butylene terephthalate.

[0020] PBF: Poly(butylene 2,5-furandicarboxylate), also known as polymer of butylene 2,5-furandicarboxylate.

[0021] PBBf: Poly(butylene bisfuranate), also known as polymer of butylene bisfuranate.

[0022] PEF: Poly(ethylene 2,5-furandicarboxylate), also known as polymer of ethylene 2,5-furandicarboxylate.

[0023] Chemical structure

[0024]

[0025] The present disclosure describes an improved electrical connector (also referred to herein as a "connector") by replacing a polybutylene terephthalate (PBT)-based electrical connector with a poly(2,5-furandicarboxylate) (PBF)-based electrical connector. PBF is an aromatic polyester that is chemically similar to PBT and exhibits similar chemical and physical properties, and is therefore a potential replacement material for PBT. While PBT is derived from fossil fuel-based feedstocks, PBF is derived from bio-based feedstocks and has a lower carbon footprint than PBT.

[0026] PBF is similar to PBT in that its chemical structure differs only by the inclusion of a furan ring instead of a benzene ring. The basic building block of PBF is 2,5 furan dicarboxylic acid (FDCA). FDCA is produced via the catalytic conversion of 5-hydroxymethylfurfural (HMF), which can be produced by the acid-catalyzed dehydration of fructose. Similar to PBT, PBF can be synthesized in a two-stage process via melt polycondensation. First, dimethyl 2,5-furandicarboxylate (DMFD) is formed via the esterification of FDCA with methanol. Second, bis(hydroxybutyl)-2,5-furandicarboxylate (BHFD) is formed via the transesterification of DMFD with 1,4-butanediol (BD). PBF is then formed from BHFD in the polycondensation stage with the elimination of BD. For example, M. Papageorgiou et al. describe the process in "Evaluation of polyesters from renewable resources as alternatives to the current fossil-based polymers. Phase transitions of poly(butylene 2,5-furan-dicarboxylate), Polymer 55, 3846 (2014)". For example, JC Morales-Huerta et al. describe an alternative synthesis method using ring-opening polymerization in "Poly(alkylene 2,5-furandicarboxylate)s(PEF and PBF) by ring opening, Polymer 87, 148 (2016)".

[0027] Due to their chemical similarities, PBF and PBT generally exhibit similar properties. However, compared with PBT, PBF exhibits superior gas diffusion barrier properties for oxygen and CO2. This stems from the lower symmetry of the furan ring in PBF compared with the benzene ring in PBT, resulting in very limited local motion in PBF, especially hindered furan ring flipping and restricted carbonyl rotation, which will reduce the diffusion of small molecules.

[0028] Electrical connectors (male or female) can be injection molded using thermoplastic resins. Examples include polyamides (such as nylon), polyacetals (such as polyoxymethylene), polyolefins (such as polypropylene), polyesters (such as polyethylene terephthalate and PBT), as well as polycarbonates and polyphenylene sulfide. Among them, PBT is generally used because PBT has the desired mechanical properties (e.g., tensile modulus and tensile strength), electrical properties, heat resistance, water resistance, and good dimensional stability required for electrical connectors. In addition, PBT is a semi-crystalline resin and has high productivity by achieving a fast crystallization rate and curing in a short time. Due to these advantages, PBT is often used as a molding material for the housing of automotive connectors. In conventional practice, reinforcing additives (e.g., fibers) are added to PBT to strengthen the PBT as a molding material for the connector housing. Due to the chemical similarity between PBF and PBT, the same technology of adding reinforcing additives can be applied to PBF.

[0029] A disadvantage of PBF in use in automotive connectors compared to PBT is that it has a lower melting temperature of 168°C to 186°C compared to PBT's melting temperature of 221°C to 225°C. The present disclosure also describes blends of PBF and PBT to overcome this disadvantage. Thus, savings in GHG emissions and non-renewable energy use (NREU) are achieved, but are reduced in proportion to the reduction in PBT content.

[0030] To overcome the disadvantage of the relatively low melting temperature of PBF (168°C to 186°C) as it relates to automotive connectors, the present disclosure also describes blends and copolymers of PBF and PEF. The melting temperature of PEF is in the range of 202°C-220°C. Similar to PBF, the basic structural unit of PEF is FDCA. The resulting PEF is a bio-based polymer; therefore, significant savings in GHG emissions and NREUs are achieved through the combination of PBF and PEF.

[0031] Compared to PBT, PBF and PEF have slower crystallization rates due to the rigidity of the furan ring. The present disclosure also describes the use of nucleating agents, additives and fillers to increase the crystallization rate and nucleation density of PBF or PEF and related blends, copolymers and composites. The present disclosure also describes the use of poly(butylene bisfuranate) (PBBf), which is also derived from FDCA and 2,2'-bisfuran-5,5'-dicarboxylic acid (BFDCA), in electrical connectors. PBBf has a melting temperature of 215°C to 217°C. BFDCA, which is a precursor of PBBf, is derived from the homogeneous Pd-catalyzed oxidative autocoupling of methyl 2-furoate (a renewable raw material) with molecular oxygen as an oxidant, as described in Mingchun Ye et al., “Oxidative coupling of 2-methylfuroate: Ascalable synthesis of dimethyl 2,2'-bifuran-5,5'-dicarboxylate”, Applied Catalysis A: General, 619, 118138 (2021).

[0032] The relevant properties of PBT, PBF, PBBf and PEF are listed in Table 1. These properties include tensile modulus, tensile strength, elongation at break, glass transition temperature (Tg) and melting temperature (Tm).

[0033] Table 1: Comparison of properties of PBT, PBF and PBBf.

[0034]

[0035] Figure 1 A perspective view of an exemplary electrical connector housing 100 (e.g., a connector shell) is shown. The connector housing 100 shows an exemplary housing for a female connector. The connector housing 100 is formed by integrally including a housing body 102 and a locking portion 104 on the top of the housing body 102. The locking portion 104 can be connected to a mating connector (not shown). The housing body 102 defines a plurality of mating terminal insertion holes 106, into which the mating terminals can be inserted, respectively. The back side of each of the mating terminal insertion holes 106 can be connected to a terminal housing chamber, into which a terminal fitting attached to an end of a wire can be inserted. Figure 1 The connector housing 100 is provided with two rows of mating terminal insertion holes 106 arranged one on top of the other. Each row includes ten mating terminal insertion holes 106 arranged transversely.

[0036] Figure 2A and Figure 2B A schematic diagram showing the configuration of an exemplary electrical connector 200 is shown. Figure 2A is a perspective view of an electrical connector, and Figure 2B 2 is a cross-sectional view thereof. The electrical connector 200 is configured to be used, for example, in an electronic control unit (ECU) housing of a motor vehicle or the like, and is assembled in and connected to other corresponding connection devices. As shown in the figure, the electrical connector 200 includes a terminal housing 202 having a housing cavity 204 formed therein and a terminal 206 (e.g., an electrical contact) as an insertion component.

[0037] Figure 2A and Figure 2B The electrical connector 200 includes a plurality of terminals 206. Each of the terminals 206 has a shape in which a rod-shaped conductive metal (e.g., an electrical contact) is bent at a right angle along its path. When the terminal housing 202 is molded, the terminals 206 are embedded together in the terminal housing 202 and are arranged at a specified position. In the terminal 206, a terminal external connection section 210 corresponding to a portion extending in a vertical direction leaks out and extends from a back rib section 208 formed on the back side of the terminal housing 202, and is connected to an external circuit board, etc. In addition, a terminal internal connection section 212 corresponding to a portion extending in a horizontal direction has a terminal tip 214 exposed in the housing cavity 204 by a specified length.

[0038] Figure 3 An exemplary molding machine 300 for performing an injection molding process is shown. In the injection molding machine 300, one or more fixed molds 301 and movable molds 302, the same number as the number of fixed molds 301, are arranged to face each other. Each set of fixed molds 301 and movable molds 302 are clamped to form a cavity in the shape of an injection molded part. The molten material is injected into the cavity between the fixed mold 301 and the movable mold 302, and the fixed mold and the movable mold remain in contact with the molten material for a specified amount of time until the molten material is sufficiently cooled to solidify. Then, the movable mold 302 is moved a specified amount in the mold opening direction by servo motor control or hydraulic control, so that the movable mold is retracted from the relative fixed mold 301, so that the injection molded part can be discharged. The molding machine 300 can be used to manufacture electrical connectors and / or electrical housings (such as those related to thermoplastics) from thermoplastics. Figure 1 , Figure 2A and Figure 2B The thermoplastic comprises PBF; PBBf; a polymer blend (also referred to as a "blend") or copolymer of BF, BBf, EF or BT in any combination; any combination thereof; or any combination thereof in a blend with PBT; or any combination thereof in a blend with PEF.

[0039] Electrical connector

[0040] According to some embodiments of the present disclosure, an electrical connector includes an electrical housing and an electrical contact. In one embodiment, the electrical contact is coupled to the electrical housing. The electrical housing can be configured as a female socket including a cavity, the cavity including the electrical contact, or as a male plug including a protruding member, the protruding member including the electrical contact. An exemplary electrical housing of the present disclosure includes Figure 1 The housing 100 and the Figure 2A and Figure 2B The housing 202 is described.

[0041] In a preferred embodiment, the shell may comprise PBF, PBBf, a copolymer of (i) BF and (ii) BBf, a copolymer of (i) EF and (ii) one or both of BF and BBf, a copolymer of (i) BT and (ii) one or more of BF, BBf and EF, or any combination thereof. The polymers and / or copolymers may be alone or in any combination as a polymer blend (mixture). For example, the shell may comprise a copolymer of EF and BF, a copolymer of EF and BBf, a copolymer of EF, BF and BBf, a copolymer of BT and BF, a copolymer of BT and BBf, a copolymer of BT and EF, a copolymer of BT, BF and BBf, a copolymer of BT and EF, a copolymer of BT, BF and BBf, a copolymer of BT, BF and EF, a copolymer of BT, BBf and EF, a copolymer of BT, EF, BF and BBf, or any combination thereof. For example, the shell comprises a polymer blend of PBF and PBBf, a polymer blend of PEF and PBF, a polymer blend of PEF and PBBf, a polymer blend of PEF, PBF, and PBBf, a polymer blend of PBT and PBF, a polymer blend of PBT and PBBf, a polymer blend of PBT and PEF, a polymer blend of PBT, PBF, and PBBf, a polymer blend of PBT, PBF, and PEF, a polymer blend of PBT, PBBf, and PEF, a polymer blend of PBT, PBF, PBBf, and PEF, or any combination thereof.

[0042] The shell may comprise any of the following polymers or copolymers, alone or in any combination as a polymer blend: PBF, PBBf, a blend (mixture) or copolymer of BF and BBf, a blend or copolymer of EF with one or both of BF and BBf, or a blend or copolymer of BT with one or more of BF, BBf and EF.

[0043] The copolymer of BT and BF, BT and BBf, or BT, BF and BBf can contain 1 wt%-99 wt%, or 1 wt%-20 wt% (e.g., 1 wt%-10 wt%, or 10 wt%-20 wt%), or 20 wt%-40 wt% (e.g., 20 wt%-30 wt%, or 30 wt%-40 wt%), or 40 wt%-60 wt% (e.g., 40 wt%-50 wt% or 50 wt%-60 wt%), or 60 wt%-80 wt% (e.g., 60 wt%-70 wt% or 70 wt%-80 wt%), or 80 wt%-99 wt% (80 wt%-90 wt%, or 90 wt%-99 wt%) of BT.

[0044] In some embodiments, the shell further comprises PBT. The shell may comprise, for example, a polymer blend comprising PBT and any combination of PBF, PBBf, a copolymer of BF and BBf, a copolymer of BT and BF, a copolymer of BT and BBf, or a copolymer of BT, BF, and BBf.

[0045] In some embodiments, the shell comprises a blend of PBT and PBF. The blend of PBT and PBF can comprise 1 wt%-99 wt%, or 1 wt%-20 wt% (e.g., 1 wt%-10 wt%, or 10 wt%-20 wt%), or 20 wt%-40 wt% (e.g., 20 wt%-30 wt%, or 30 wt%-40 wt%), or 40 wt%-60 wt% (e.g., 40 wt%-50 wt% or 50 wt%-60 wt%), or 60 wt%-80 wt% (e.g., 60 wt%-70 wt% or 70 wt%-80 wt%), or 80 wt%-99 wt% (80 wt%-90 wt%, or 90 wt%-99 wt%) of PBT.

[0046] In some embodiments, the shell comprises a blend of PBT and PBBf. The blend of PBT and PBBf can include 1 wt%-99 wt%, or 1 wt%-20 wt% (e.g., 1 wt%-10 wt%, or 10 wt%-20 wt%), or 20 wt%-40 wt% (e.g., 20 wt%-30 wt%, or 30 wt%-40 wt%), or 40 wt%-60 wt% (e.g., 40 wt%-50 wt% or 50 wt%-60 wt%), or 60 wt%-80 wt% (e.g., 60 wt%-70 wt% or 70 wt%-80 wt%), or 80 wt%-99 wt% (80 wt%-90 wt%, or 90 wt%-99 wt%) of PBT.

[0047] In some embodiments, the shell comprises a blend of PBT with a copolymer of BF and BBf. The blend of PBT with a copolymer of BF and BBf can comprise 1 wt%-99 wt%, or 1 wt%-20 wt% (e.g., 1 wt%-10 wt%, or 10 wt%-20 wt%), or 20 wt%-40 wt% (e.g., 20 wt%-30 wt%, or 30 wt%-40 wt%), or 40 wt%-60 wt% (e.g., 40 wt%-50 wt% or 50 wt%-60 wt%), or 60 wt%-80 wt% (e.g., 60 wt%-70 wt% or 70 wt%-80 wt%), or 80 wt%-99 wt% (80 wt%-90 wt%, or 90 wt%-99 wt%) of PBT.

[0048] In some embodiments, the shell comprises a copolymer of BF and BBf. The copolymer of BF and BBf can comprise 1 wt%-99 wt%, or 1 wt%-20 wt% (e.g., 1 wt%-10 wt%, or 10 wt%-20 wt%), or 20 wt%-40 wt% (e.g., 20 wt%-30 wt%, or 30 wt%-40 wt%), or 40 wt%-60 wt% (e.g., 40 wt%-50 wt% or 50 wt%-60 wt%), or 60 wt%-80 wt% (e.g., 60 wt%-70 wt% or 70 wt%-80 wt%), or 80 wt%-99 wt% (80 wt%-90 wt%, or 90 wt%-99 wt%) of BBf.

[0049] In some embodiments, the shell comprises a blend of PBF and PBBf. The blend of PBF and PBBf can comprise 1 wt%-99 wt%, or 1 wt%-20 wt% (e.g., 1 wt%-10 wt%, or 10 wt%-20 wt%), or 20 wt%-40 wt% (e.g., 20 wt%-30 wt%, or 30 wt%-40 wt%), or 40 wt%-60 wt% (e.g., 40 wt%-50 wt% or 50 wt%-60 wt%), or 60 wt%-80 wt% (e.g., 60 wt%-70 wt% or 70 wt%-80 wt%), or 80 wt%-99 wt% (80 wt%-90 wt%, or 90 wt%-99 wt%) of PBF.

[0050] In some embodiments, the shell comprises a copolymer of BF and EF. The copolymer of BF and EF can contain 1 wt%-99 wt%, or 1 wt%-20 wt% (e.g., 1 wt%-10 wt%, or 10 wt%-20 wt%), or 20 wt%-40 wt% (e.g., 20 wt%-30 wt%, or 30 wt%-40 wt%), or 40 wt%-60 wt% (e.g., 40 wt%-50 wt% or 50 wt%-60 wt%), or 60 wt%-80 wt% (e.g., 60 wt%-70 wt% or 70 wt%-80 wt%), or 80 wt%-99 wt% (80 wt%-90 wt%, or 90 wt%-99 wt%) of BF.

[0051] In some embodiments, the shell comprises a blend of PBF and PEF. The blend of PBF and PEF can comprise 1 wt%-99 wt%, or 1 wt%-20 wt% (e.g., 1 wt%-10 wt%, or 10 wt%-20 wt%), or 20 wt%-40 wt% (e.g., 20 wt%-30 wt%, or 30 wt%-40 wt%), or 40 wt%-60 wt% (e.g., 40 wt%-50 wt% or 50 wt%-60 wt%), or 60 wt%-80 wt% (e.g., 60 wt%-70 wt% or 70 wt%-80 wt%), or 80 wt%-99 wt% (80 wt%-90 wt%, or 90 wt%-99 wt%) of PBF.

[0052] The weight percentage of each component in a blend or copolymer is selected based on the desired properties to be achieved in the material. m =221℃-225℃) and PBF(T m =168°C-186°C) in a blend, the weight percentages of PBT and PBF can be selected to obtain a desired melting temperature of the blend that is between the melting temperatures of the pure polymers.

[0053] In some embodiments, the shell further comprises additives. The additives may be selected from, but are not limited to, antioxidants, ultraviolet (UV) stabilizers, flame retardants, anti-hydrolysis agents, color pigments, nucleating agents, additives or fillers that increase crystallization rate and / or mechanical strength, additives for laser engraving, lubricants, and waxes. For example, the shell comprises 0.1 wt%-3 wt%, 0.1 wt%-5 wt% or 0.1 wt%-10 wt% of an antioxidant, such as a hindered phenol, a thioether, a phosphite or any combination thereof; for example, the shell comprises 0.1 wt%-10 wt% of a UV stabilizer, such as a benzotriazole, a hydroxybenzophenone or any combination thereof; for example, the shell comprises 1 wt%-40 wt%, 2 wt%-30 wt% or 5 wt%-25 wt% of a flame retardant, such as a phosphate ether, magnesium hydroxide, aluminum diethylphosphinate or any combination thereof; and / or for example, the shell comprises 0.1 wt%-10 wt% of an anti-hydrolysis agent, such as an acid scavenger; and / or for example, the shell comprises 0.1 wt%-20 wt% of a color pigment, such as anthraquinone, iron oxide, carbon black, titanium dioxide, orange pigment. Lubricants may include, for example, polytetrafluoroethylene (PTFE), esters of fatty acids and / or metal salts, such as zinc stearate, calcium stearate, and adipic acid glycol polyester (AAGP). Nucleating agents or crystallization rate enhancers may include, for example, sodium benzoate, sodium salts of saccharin, boron nitride, organic acids, metal salts, inorganic substances such as CNT, talcum powder, glass fibers, or metal carbonates and / or coupling agents. Waxes may include, for example, ethylene bis stearamide.

[0054] In some embodiments, the additive is a color-changing additive for laser lettering. The additive has no inherent color or substantially no inherent color (only slight inherent color) in the visible spectrum range (light wavelength of about 380nm to 750nm), and produces a mark with high color contrast in the visible range under the action of a laser with a wavelength outside the visible range (lower than 380nm or higher than 750nm). For example, the color contrast can be produced by converting the additive into a colored product under the action of a laser from a Nd-YAG laser (wavelength 1064nm) or an excimer laser (wavelength 308nm to 351nm). Any additive having the above characteristics can be used for laser lettering, such as copper phosphate, copper sulfate, copper hydroxide phosphate and copper thiocyanate, for example 0.02% to 5% Cu3(PO4)2·Cu(OH)2.

[0055] In some embodiments, the additive is a strengthening additive. For example, the electrical enclosure comprises 1 wt%-60 wt%, 2 wt%-50 wt%, or 5 wt%-40 wt% of a strengthening additive. The strengthening additive may be selected from, but not limited to, glass fiber, carbon fiber, talc, cellulose, bamboo, cork, hardwood, flax, kenaf, jute, ramie, coconut husk fiber, kapok, sisal, henaquin fiber, abaca, hemp, bagasse, wheat straw, rice husk, rattan, Indian hemp fiber, and any combination thereof.

[0056] In some embodiments, the electrical housing of the electrical connector has a tensile modulus in the range of about 1 GPa-4 GPa, 2 GPa-4 GPa, 1 GPa-7 GPa, 3 GPa-7 GPa, or 5 GPa-7 GPa, and a tensile strength in the range of about 20 MPa-70 MPa, 40 MPa-70 MPa, 20 MPa-90 MPa, 40 MPa-90 MPa, 50 MPa-150 MPa, 90 MPa-150 MPa, 20 MPa-95 MPa, or 40 MPa-95 MPa.

[0057] Exemplary ranges of tensile modulus and tensile strength are provided in Examples I to X. Compounding PBF and / or PBBf or copolymers of BF and BBf with reinforcing additives increases the tensile modulus and tensile strength of electrical enclosures. For example, the tensile modulus of PBF is in the range of 1 GPa-4 GPa, preferably in the range of 2 GPa-4 GPa, and the maximum tensile strength of PBF is in the range of 20 MPa-70 MPa, preferably in the range of 40 MPa-70 MPa; the tensile modulus of the composite material of PBF and reinforcing additive is in the range of 3 GPa-7 GPa, preferably in the range of 5 GPa-7 GPa, and the maximum tensile strength of the composite material of PBF and reinforcing additive is in the range of 50 MPa-150 MPa, preferably in the range of 90 MPa-1 The tensile modulus of the PBF / PBT blend is in the range of 1 GPa-4 GPa, preferably in the range of 2 GPa-4 GPa, and the maximum tensile strength of the PBF / PBT blend is in the range of 20 MPa-70 MPa, preferably in the range of 40 MPa-70 MPa; the tensile modulus of PBBf is in the range of 1 GPa-4 GPa, preferably in the range of 2 GPa-4 GPa, and the maximum tensile strength of PBBf is in the range of 40 MPa-90 MPa, preferably in the range of 55 MPa-9 The tensile modulus of the composite material of PBBf and the reinforcing additive is in the range of 3GPa-7GPa, preferably in the range of 5GPa-7GPa, and the maximum tensile strength of the composite material of PBBf and the reinforcing additive is in the range of 50MPa-150MPa, preferably in the range of 90MPa-150MPa; the tensile modulus of the PBF / PBBf blend or the copolymer of BF and BBf is in the range of 1GPa-4GPa, preferably in the range of 2GPa-4GPa, and the PBF / PBBf blend The maximum tensile strength of the PBF / PBBf blend or the copolymer of BF and BBf is in the range of 20 MPa-90 MPa, preferably in the range of 40 MPa-90 MPa, the tensile modulus of the PBF / PBBf blend or the copolymer of BF and BBf with a reinforcing additive is in the range of 3 GPa-7 GPa, preferably in the range of 5 GPa-7 GPa, and the maximum tensile strength of the PBF / PBBf blend or the copolymer of BF and BBf with a reinforcing additive is in the range of 50 MPa-150 MPa, preferably in the range of 90 MPa-150 MPa.

[0058] The tensile modulus of the PBF / PEF blend or the copolymer of BF and EF is in the range of 1 GPa-4 GPa, preferably in the range of 2 GPa-4 GPa, and the maximum tensile strength of the PBF / PEF blend or the copolymer of BF and EF is in the range of 20 MPa-95 MPa, preferably in the range of 40 MPa-95 MPa, the tensile modulus of the PBF / PEF blend or the copolymer of BF and EF with a reinforcing additive is in the range of 3 GPa-7 GPa, preferably in the range of 5 GPa-7 GPa, and the maximum tensile strength of the PBF / PBBf blend or the copolymer of BF and BBf with a reinforcing additive is in the range of 50 MPa-150 MPa, preferably in the range of 90 MPa-150 MPa; PBB The tensile modulus of the PBBf / PEF blend or the copolymer of BBf and EF is in the range of 1 GPa-4 GPa, preferably in the range of 2 GPa-4 GPa, and the maximum tensile strength of the PBBf / PEF blend or the copolymer of BBf and EF is in the range of 20 MPa-95 MPa, preferably in the range of 40 MPa-95 MPa, the tensile modulus of the PBBf / PEF blend or the copolymer of BBf and EF with a reinforcing additive is in the range of 3 GPa-7 GPa, preferably in the range of 5 GPa-7 GPa, and the maximum tensile strength of the PBBf / PEF blend or the copolymer of BBf and EF with a reinforcing additive is in the range of 50 MPa-150 MPa, preferably in the range of 90 MPa-150 MPa.

[0059] In some embodiments, the electrical housing of the electrical connector has a heat deflection temperature in the range of 60°C to 150°C, 80°C to 150°C, or 100°C to 150°C.

[0060] PBF can be synthesized as described in Papageorgiou et al., “Evaluation of polyesters from renewable resources as alternatives to the current fossil-based polymers. Phase transitions of poly(butylene 2,5-furan-dicarboxylate)”, Polymer 55, 3846 (2014) or JC Morales-Huerta et al., “Poly(alkylene 2,5-furandicarboxylate)s (PEF and PBF) by ring opening”, Polymer 87, 148 (2016). BFDCA (precursor of PBBf) can be synthesized as described in MingchunYe et al. "Oxidative coupling of 2-methyl furoate: A scalable synthesis of dimethyl 2,2'-bifuran-5,5'-dicarboxylate", Applied Catalysis A: General, 619, 118138 (2021), and PBBf can be synthesized from the precursor BFDCA as described in T.Kainulainen et al., "Utilizing Furfural-Based Bifuran Diester as Monomer and Comonomer for High-Performance Bioplastics: Properties of Poly(butylene furanoate), Poly(butylenebifuranoate), and Their Copolyesters", Biomacromolecules 21, 743 (2020). The synthesis of random copolymers of BF and BBf is also described in Kainulainen et al., Biomacromolecules 21, 743-752 (2020). Blends of PBF and PEF are described in Poulopoulou et al., “Green polymeric materials: On the dynamic homogeneity and miscibility of furan-based polyester blends” Polymer 174, 187-199 (2019).All references cited herein are incorporated by reference in their entirety.

[0061] Process for manufacturing electrical connectors

[0062] Figure 4 4 is a flowchart illustrating a process 400 for manufacturing an electrical connector, particularly a housing for an electrical connector. In some embodiments, the electrical connector corresponds to Figure 1 as well as Figure 2A and Figure 2B In some embodiments, the electrical housing corresponds to the exemplary connector described in Figure 1 as well as Figure 2A and Figure 2B The housing 100 or housing 202 of the electrical connector or the connecting terminal device is described.

[0063] At 402, process 400 includes obtaining one or more materials. In some embodiments, the one or more materials are selected from the following: PBF, PBBf, a copolymer of (i) BF and (ii) BBf, a copolymer of (i) EF and (ii) one or both of BF and BBf, a copolymer of (i) BT and (ii) one or more of BF, BBf, and EF, or any combination thereof. The polymers and / or copolymers may be alone or in any combination as a polymer blend (mixture). For example, the one or more materials may include a copolymer of EF and BF, a copolymer of EF and BBf, a copolymer of EF, BF, and BBf, a copolymer of BT and BF, a copolymer of BT and BBf, a copolymer of BT and EF, a copolymer of BT, BF, and BBf, a copolymer of BT and EF, a copolymer of BT, BF, and BBf, a copolymer of BT, BF, and EF, a copolymer of BT, BF, BBf, and EF, or any combination thereof. For example, the one or more materials include a polymer blend of PBF and PBBf, a polymer blend of PEF and PBF, a polymer blend of PEF and PBBf, a polymer blend of PEF, PBF, and PBBf, a polymer blend of PBT and PBF, a polymer blend of PBT and PBBf, a polymer blend of PBT and PEF, a polymer blend of PBT, PBF, and PBBf, a polymer blend of PBT, PBF, and PEF, a polymer blend of PBT, PBBf, and PEF, a polymer blend of PBT, PBF, PBBf, and PEF, or any combination thereof.

[0064] In some embodiments, process 400 includes obtaining a composition of materials. For example, one or more materials include or are in the form of a composition that includes a polymer, including PBF, PBBf, or a copolymer of BF and BBf (e.g., copolyester), and other materials (e.g., additives, polymers such as PBT or PEF). The one or more materials and / or compositions of materials may include any of the materials described with respect to the materials contained in the electrical connector of the present disclosure.

[0065] In some embodiments, the composition further comprises PEF. In such embodiments, process 400 further comprises mixing the PEF with a polymer, blend or copolymer of one or more materials to form a blend of the PEF and a polymer, blend or copolymer of one or more materials to form a blend of the PEF. The mixing may be performed before extruding the solutionized composition to produce a compounded pellet.

[0066] In some embodiments, obtaining the one or more materials or compositions may include heating the one or more materials or compositions for a period of time (e.g., heating at a temperature in the range of 80° C. to 120° C. for 4 to 8 hours). The heating dries the one or more materials or compositions. For example, the moisture content of PBF, PBBf, PEF, or PBT may be less than 0.2%, and preferably less than 0.03%.

[0067] In some embodiments, it is necessary to compound one or more materials or compositions to form pellets suitable for injection molding, as described below with respect to Example VIII. Compounding can include solutionizing one or more materials, mixing the materials together, and extruding one or more materials to produce pellets.

[0068] At 404, process 400 includes solutionizing one or more materials or compositions. Solutionizing includes melt mixing one or more materials or compositions. For example, PBT has a melting point of 221°C-225°C, PBF has a melting point of 168°C-186°C, PEF has a melting point of 202°C-220°C, and PBBf has a melting point of 215°C-217°C. As described in Example X below, the materials are mixed in a molten state. In one embodiment, mixing PBF and / or PBBf with any of the above-mentioned additives includes mixing PBF pellets and / or PBBf pellets with additives in a molten state. In another embodiment, compounding PBF and PBT includes mixing PBF pellets and PBT pellets in a molten state. In another embodiment, mixing PBF and PBT with any of the above-mentioned additives includes mixing PBF and PBT pellets with additives in a molten state. In another embodiment, mixing BF and BBf copolymers with any of the above-mentioned additives comprises mixing BF and BBf copolymer pellets with the additives in a molten state. In another embodiment, mixing PBF and PEF with any of the above-mentioned additives comprises mixing PBF and PEF pellets with the additives in a molten state. In another embodiment, mixing BF and EF copolymers with any of the above-mentioned additives comprises mixing BF and EF copolymer pellets with the additives in a molten state. In another embodiment, mixing PBBf and PEF with any of the above-mentioned additives comprises mixing PBBf and PEF pellets with the additives in a molten state. In another embodiment, mixing BBf and EF copolymers with any of the above-mentioned additives comprises mixing BBf and EF copolymer pellets with the additives in a molten state.

[0069] At 406, process 400 includes extruding one or more materials of solid solution or the composition of solid solution to produce the pellets of compounding.Extrusion refers to a material formation process, wherein the material is forced to flow (e.g., by pressure) through the die of an extruder (or extruder) to convert the material into a desired shape, such as a pellet.Extrusion can be used to mix two or more materials by adding two or more materials to an extruder and forcing them to flow along the extruder.Different materials can be fed into the extruder individually or as a mixture to form the pellets of compounding.Extruder can be a single screw extruder or a twin screw extruder, wherein the twin screw extruder provides better control of the extrusion process.In some embodiments, the pellets of the compounding formed at 406 are subsequently heated to dry the pellets.

[0070] In some embodiments, one or more materials include PBF and PBT. In such embodiments, process 400 also includes blending PBF with PBT to produce compounded pellets before extruding the solutionized composition. The blend of PBT and PBF can include 1 wt %-99 wt %, or 1 wt %-20 wt % (e.g., 1 wt %-10 wt %, or 10 wt %-20 wt %), or 20 wt %-40 wt % (e.g., 20 wt %-30 wt %, or 30 wt %-40 wt %), or 40 wt %-60 wt % (e.g., 40 wt %-50 wt % or 50 wt %-60 wt %), or 60 wt %-80 wt % (e.g., 60 wt %-70 wt % or 70 wt %-80 wt %), or 80 wt %-99 wt % (80 wt %-90 wt %, or 90 wt %-99 wt %) of PBT. The weight percentages of PBT and PBF can be selected to obtain desired properties for the blend, for example, a specific melting temperature between those of the pure polymers.

[0071] In some embodiments, one or more materials include PBBf and PBT. In such embodiments, process 400 also includes blending PBBf with PBT to produce compounded pellets before extruding the composition of solid solutionization. The blend of PBT and PBBf can include 1 wt %-99 wt %, or 1 wt %-20 wt % (e.g., 1 wt %-10 wt % or 10 wt %-20 wt %), or 20 wt %-40 wt % (e.g., 20 wt %-30 wt % or 30 wt %-40 wt %), or 40 wt %-60 wt % (e.g., 40 wt %-50 wt % or 50 wt %-60 wt %), or 60 wt %-80 wt % (e.g., 60 wt %-70 wt % or 70 wt %-80 wt %), or 80 wt %-99 wt % (80 wt %-90 wt % or 90 wt %-99 wt %) of PBT. The weight percentages of PBBf and PBT can be selected to obtain desired properties for the blend, for example, a specific melting temperature between those of the pure polymers.

[0072] In some embodiments, one or more materials include PBF and PBBf. In such embodiments, process 400 also includes blending PBF with PBBf to produce compounded pellets before extruding the solutionized composition. The blend of PBF and PBBf can include 1 wt%-99 wt%, or 1 wt%-20 wt% (e.g., 1 wt%-10 wt%, or 10 wt%-20 wt%), or 20 wt%-40 wt% (e.g., 20 wt%-30 wt%, or 30 wt%-40 wt%), or 40 wt%-60 wt% (e.g., 40 wt%-50 wt% or 50 wt%-60 wt%), or 60 wt%-80 wt% (e.g., 60 wt%-70 wt% or 70 wt%-80 wt%), or 80 wt%-99 wt% (80 wt%-90 wt%, or 90 wt%-99 wt%) of PBF. The weight percentages of PBF and PBBf can be selected to obtain desired properties for the blend, for example, a specific melting temperature between those of the pure polymers.

[0073] In some embodiments, one or more materials include PBF and PEF. In such embodiments, process 400 also includes blending PBF with PEF to produce compounded pellets before extruding the solutionized composition. The blend of PBF and PEF can include 1 wt%-99 wt%, or 1 wt%-20 wt% (e.g., 1 wt%-10 wt%, or 10 wt%-20 wt%), or 20 wt%-40 wt% (e.g., 20 wt%-30 wt%, or 30 wt%-40 wt%), or 40 wt%-60 wt% (e.g., 40 wt%-50 wt% or 50 wt%-60 wt%), or 60 wt%-80 wt% (e.g., 60 wt%-70 wt% or 70 wt%-80 wt%), or 80 wt%-99 wt% (80 wt%-90 wt%, or 90 wt%-99 wt%) of PBF. The weight percentages of PBF and PEF can be selected to obtain desired properties for the blend, for example, a specific melting temperature between those of the pure polymers.

[0074] In some embodiments, one or more materials include PBBf and PEF. In such embodiments, process 400 also includes blending PBBf with PEF to produce compounded pellets before extruding the solutionized composition. The blend of PBBf and PEF can include 1 wt%-99 wt%, or 1 wt%-20 wt% (e.g., 1 wt%-10 wt%, or 10 wt%-20 wt%), or 20 wt%-40 wt% (e.g., 20 wt%-30 wt%, or 30 wt%-40 wt%), or 40 wt%-60 wt% (e.g., 40 wt%-50 wt% or 50 wt%-60 wt%), or 60 wt%-80 wt% (e.g., 60 wt%-70 wt% or 70 wt%-80 wt%), or 80 wt%-99 wt% (80 wt%-90 wt%, or 90 wt%-99 wt%) of PBBf. The weight percentages of PBBf and PEF can be selected to obtain desired properties for the blend, for example, a specific melting temperature between those of the pure polymers.

[0075] In some embodiments, the one or more materials include one or more copolymers of BF, BBf, EF or BT in any combination, and one or more polymers of PBF, PBBf, PEF or PBT in any combination. In such embodiments, process 400 also includes blending the copolymer with the polymer to produce compounded pellets before extruding the solutionized composition. Blends of copolymers and polymers may contain 1 wt%-99 wt%, or 1 wt%-20 wt% (e.g., 1 wt%-10 wt%, or 10 wt%-20 wt%), or 20 wt%-40 wt% (e.g., 20 wt%-30 wt%, or 30 wt%-40 wt%), or 40 wt%-60 wt% (e.g., 40 wt%-50 wt%, or 50 wt%-60 wt%), or 60 wt%-80 wt% (e.g., 60 wt%-70 wt%, or 70 wt%-80 wt%), or 80 wt%-99 wt% (80 wt%-90 wt%, or 90 wt%-99 wt%) of PBF or BF. The weight percentages of the copolyesters of BF, BBf, EF and / or BT and the polyesters of PBF, PBBf, PEF and / or PBT may be selected to obtain the desired properties of the blend, for example, a specific melting temperature between those of the pure polymers.

[0076] In some embodiments, the composition includes any one of the above-mentioned materials and one or more additives. One or more additives can be selected from the first additive, and the first additive includes but is not limited to antioxidants, UV stabilizers, flame retardants, anti-hydrolysis agents, color pigments, lubricants, waxes, nucleating agents, additives for laser lettering and any combination thereof. Alternatively or in addition, one or more additives may include a second additive. The second additive may include a reinforcing additive selected from but not limited to glass fiber, carbon fiber, talcum powder and any combination thereof. Alternatively or in addition, the second additive may include but is not limited to cellulose, bamboo, cork, hardwood, flax, kenaf, jute, ramie, coconut shell fiber, kapok, sisal, Henakun fiber, Manila hemp, hemp, bagasse, straw, rice husk, rattan, Indian hemp fiber, or any combination thereof.

[0077] Process 400 also includes injection molding the compounded pellets to form the electrical enclosure. Injection molding can be performed using an injection molding machine. Figure 3 An exemplary injection molding machine is shown in . Injection molding includes heating extruded pellets comprising one or more materials or compositions to a molten state at 408, and injecting the one or more materials in a molten state into a mold at 410 to form an electrical enclosure. Process 400 optionally includes annealing the formed electrical enclosure at 60° C. or above, or at 100° C. or above, at 412. For example, annealing can be performed at 60° C.-135° C. In some embodiments, annealing is performed at 115° C. Annealing increases the crystallinity of the electrical enclosure, thereby increasing its strength and durability.

[0078] In some embodiments, the electrical enclosure prepared by process 400 can be connected to one or more electrical contacts (e.g., Figure 2A and Figure 2B The terminal electrical connector and / or electrical housing made by process 400 can be used in an electronic control unit of a motor vehicle or the like.

[0079] Example

[0080] Example I: Injection Molding Process and Properties of PBF

[0081] PBF has a melting temperature of about 168° C. to 186° C. In this embodiment, an injection molding device (e.g., Figure 3 The molding machine 300 in the embodiment of the present invention is used to inject PBF resin to form an electrical connector or an electrical housing (for example, such as Figures 1 to 2BThose described). Prior to injection molding, the PBF resin is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours. The moisture content of the environment during drying is less than 0.2% or less than 0.03%. The PBF pellets are heated to a melt (melt refers to a material in a molten state) at an injection molding machine barrel temperature of about 180°C to 230°C or about 190°C to 210°C before injection. The melt is introduced into a mold maintained at a temperature between 40°C and 100°C or at a temperature between 60°C and 80°C at an injection pressure of 50MPa-180MPa or at an injection pressure of 70MPa-120MPa. Within the selected injection molding temperature and load range, the intrinsic viscosity (IV) is between 0.5dL / g and 1.5dL / g, and the melt flow index is between 5g / 10 minutes and 70g / 10 minutes.

[0082] The tensile modulus of PBF is in the range of 1 GPa-4 GPa or 2 GPa-4 GPa, and the maximum tensile strength is in the range of 20 MPa-70 MPa or 40 MPa-70 MPa. The properties of the PBF samples are further improved by annealing the molded samples at 60°C-135°C, or at 115°C. Annealing increases the crystallinity of the electrical enclosure, thereby improving its strength and durability.

[0083] PBF can be synthesized as described in Papageorgiou et al., “Evaluation of polyesters from renewable resources as alternatives to the current fossil-based polymers. Phase transitions of poly(butylene 2,5-furan-dicarboxylate)”, Polymer 55, 3846 (2014) or JC Morales-Huerta et al., “Poly(alkylene 2,5-furandicarboxylate)s (PEF and PBF) by ring opening”, Polymer 87, 148 (2016).

[0084] Example II: Injection Molding Process for PBF Compounded with Additives

[0085] For practical applications, the PBF resin can be compounded with a variety of additives (see Example VIII for compounding). For example, 1 wt% to 60 wt% of one or more additives (including glass fiber, carbon fiber, talc or natural fillers) can be added for mechanical reinforcement. Natural fillers refer to plant-based filler materials derived from plants (grasses, shrubs, trees, etc.). Natural fillers can include, but are not limited to, cellulose, bamboo, cork, hardwood, flax, kenaf, jute, ramie, coconut husk fiber, kapok, sisal, henaquin fiber, abaca, hemp, bagasse, wheat straw, rice husk, rattan or Indian hemp fiber.

[0086] In this embodiment, 1 wt %-40 wt % of flame retardant, such as phosphate ether, magnesium hydroxide or aluminum diethylphosphinate, can be added. 0.1 wt %-10 wt % of hindered phenol, thioether, phosphite or combination can be added as antioxidant. 0.1 wt %-10 wt % of acid scavenger can be added as anti-hydrolysis agent. 0.1 wt %-10 wt % of benzotriazole and hydroxybenzophenone can be added as UV stabilizer. Color pigments can be added as needed at ≤20 wt %. Other additives may include: lubricants, such as polytetrafluoroethylene (PTFE), esters of fatty acids and metal salts (such as zinc stearate, calcium stearate and adipic acid glycol polyester (AAGP)); nucleating agents, such as sodium benzoate, sodium salt of saccharin, boron nitride, organic acids, metal salts, inorganic substances (such as CNT, talc, glass fiber or metal carbonate); and coupling agents and waxes, such as ethylene bis stearamide.

[0087] Using an injection molding device (e.g., Figure 3 The molding machine 300 described herein can be used to injection mold the compounded PBF composite pellets to form an electrical housing or an electrical connector (e.g., such as the one described herein). Figures 1 to 2B Those described). Prior to injection molding, the PBF composite is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours. The moisture content during drying is less than 0.2% or less than 0.03%. The PBF pellets are heated to about 180°C to 230°C or 190°C to 210°C, and then the melt is injected into a mold maintained at a temperature between 40°C and 100°C or between 60°C and 80°C at a pressure of 50MPa-220MPa or a pressure of 90MPa-150MPa. Within the selected injection molding temperature and load range, the intrinsic viscosity (IV) is between 0.5dL / g and 1.5dL / g, and the melt flow index is between 5g / 10min and 70g / 10min.

[0088] The tensile modulus of the composites of PBF and the reinforcing additives is in the range of 3 GPa-7 GPa, or in the range of 5 GPa-7 GPa, and the maximum tensile strength is in the range of 50 MPa-150 MPa, or in the range of 90 MPa-150 MPa.

[0089] Example III: Injection Molding Process for PBF / PBT Blends

[0090] As previously mentioned, PBF has a melting temperature of about 168°C to 186°C, while PBT has a melting point of about 221°C to 225°C. For applications that must have a higher melting temperature than pure PBF, it may be necessary to use a blend of PBF and PBT. The synthesis of such a blend is described by X. Zhang et al. in CN110229480A "A kind of preparation method of poly-furandicarboxylic acid butanediol ester and polybutyleneterephthalate (PBT) blend". The melting point of the blend varies depending on the ratio of PBF to PBT. For example, a 50 / 50 PBF / PBT blend will have a melting temperature close to 195°C to 200°C.

[0091] In this embodiment, an injection molding device as described above (e.g., Figure 3 The molding machine 300 in the embodiment of the present invention is used to inject a blend containing PBF and PBT to form an electrical housing or an electrical connector (e.g., such as Figures 1 to 2B Those described). Before injection molding, the compounded PBF and PBT pellets are air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours. In this embodiment, the moisture content during drying is less than 0.2% or less than 0.03%. The compounded PBF and PBT pellets are heated between 180°C and 240°C or between 190°C and 220°C, and then injection molded into a mold maintained at a temperature between 40°C and 120°C or a temperature between 60°C and 80°C at a pressure of 50MPa-150MPa or at a pressure of 70MPa-120MPa.

[0092] In this embodiment, the tensile modulus of the PBF / PBT blend is in the range of 1 GPa-4 GPa or 2 GPa-4 GPa, and the maximum tensile strength is in the range of 20 MPa-70 MPa or 40 MPa-70 MPa. The heat deformation temperature of the blend is expected to be between 60°C and 150°C, or between 100°C and 150°C.

[0093] Example IV: Injection Molding Process and Properties of PBBf

[0094] As previously mentioned, PBBf has a melting temperature of about 215° C. to 217° C. In this example, an injection molding device (e.g., Figure 3 The injection molding machine 300 in the embodiment of the present invention is used to inject PBBf resin to form an electrical connector or an electrical housing (for example, such as Figures 1 to 2BThose described). Before injection molding, the PBBf resin is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours. The moisture content after drying is less than 0.2% or less than 0.03%. The PBBf pellets are heated to a barrel temperature of about 220°C to 280°C or between 230°C and 260°C of an injection molding machine, and then the melt is injected into a mold set at a temperature between 60°C and 120°C or a temperature between 80°C and 110°C at an injection pressure of 50MPa-180MPa or at an injection pressure of 70MPa-120MPa. Within the selected injection molding temperature and load range, the intrinsic viscosity (IV) is between 0.5dL / g and 1.5dL / g, and the melt flow index is between 5g / 10min and 70g / 10min.

[0095] The tensile modulus of PBBf is in the range of 1 GPa-4 GPa or 2 GPa-4 GPa, and the maximum tensile strength is in the range of 40 MPa-90 MPa or 55 MPa-90 MPa.

[0096] BFDCA (precursor of PBBf) can be synthesized as described in Mingchun Ye et al., “Oxidative coupling of 2-methylfuroate: A scalable synthesis of dimethyl2,2'-bifuran-5,5'-dicarboxylate”, Applied Catalysis A: General, 619, 118138 (2021), and PBBf can be synthesized from the precursor BFDCA as described in T. Kainulainen et al., “Utilizing Furfural-Based Bifuran Diester as Monomer and Comonomer for High-Performance Bioplastics: Properties of Poly(butylenefuranoate), Poly(butylene bifuranoate), and Their Copolyesters”, Biomacromolecules 21, 743 (2020).

[0097] Example V: Injection Molding Process of PBBf for Compounding with Additives

[0098] For practical applications, PBBf resin can be compounded with a variety of additives (including but not limited to glass fiber, carbon fiber, talc or natural filler). 1 wt%-60 wt% of such additives can be added for mechanical reinforcement. 1 wt%-40 wt% of flame retardants such as phosphate ethers, magnesium hydroxide or diethyl phosphinate aluminum can be added. 0.1 wt%-10 wt% of hindered phenols, thioethers, phosphites or any combination can be added as antioxidants. 0.1 wt%-10 wt% of acid scavengers can be added as anti-hydrolysis agents. 0.1 wt%-10 wt% of benzotriazole and hydroxybenzophenone can be added as UV stabilizers. Color pigments can be added as needed at ≤20 wt%. 0.02% to 5% of color-changing additives for laser engraving can be added. Other additives may be added as needed: lubricants (such as polytetrafluoroethylene (PTFE)), esters and metal salts of fatty acids (such as zinc stearate, calcium stearate and AAGP), nucleating agents (such as sodium benzoate, sodium salt of saccharin, boron nitride, organic acids, metal salts, inorganic substances (such as CNT, talc, glass fibers or metal carbonates), and coupling agents and waxes (such as ethylene bisstearamide).

[0099] In this embodiment, an injection molding device (e.g., Figure 3 The molding machine 300 in the injection molding compounded PBBf composite pellets to form an electrical connector or electrical housing (for example, such as Figures 1 to 2B Those described). Before injection molding, the PBBf composite material is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours. The moisture content after drying is less than 0.2% or less than 0.03%. The PBBf composite pellets are heated to a temperature of about 220°C to 280°C or a temperature between 230°C and 260°C of the barrel temperature of the injection molding machine, and then the melt is injected into a mold set at a temperature between 60°C and 120°C or between 80°C and 110°C at an injection pressure of 50MPa-220MPa or at an injection pressure of 90MPa-150MPa. In the selected injection molding temperature and load range, the intrinsic viscosity (IV) is between 0.5dL / g and 1.5dL / g, and the melt flow index is between 5g / 10 and 70g / 10 minutes.

[0100] The composites of PBBf and the reinforcing additives have a tensile modulus in the range of 3 GPa-7 GPa, or in the range of 5 GPa-7 GPa, and a maximum tensile strength in the range of 50 MPa-150 MPa, or in the range of 90 MPa-150 MPa.

[0101] Example VI: Injection Molding Process for PBF-PBBf Blends and Copolymers of BF and BBf

[0102] As mentioned above, PBF has a melting temperature of about 168°C to 186°C, and PBBf has a melting point of 215°C to 217°C. Therefore, for some applications, it is necessary to blend PBF and PBBf or synthesize random copolymers (e.g., copolyesters) of furanic acid butylene ester (BF) and bisfuranic acid butylene glycol ester (BBf) derived from FDCA and BFDCA, respectively. The synthesis of random copolymers of BF and BBf is described in Kainulainen et al. "Utilizing Furfural-Based Bifuran Diester as Monomer and Comonomer for High-Performance Bioplastics: Properties of Poly (butylenefuranoate), Poly (butylene bifuranoate), and Their Copolymers", Biomacromolecules 21, 743-752 (2020).

[0103] Depending on the weight % of BF in the blend or copolymer, the melt temperature can range from 168°C to 217°C. In this embodiment, an injection molding device (e.g., Figure 3 The molding machine 300 in the embodiment of the present invention is used to inject a blend of PBF and PBBf or a copolymer of BF and BBf to form an electrical connector or an electrical housing (e.g., such as Figures 1 to 2B Those described). Before injection molding, the compounded pellets including the blend of PBF and PBBf or the copolymer of BF and BBf are air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours. The moisture content during drying is less than 0.2% or less than 0.03%. The blend or copolymer is heated between 180°C and 280°C and then injection molded into a mold maintained at a temperature between 40°C and 120°C or between 60°C and 80°C at a pressure of 50MPa-180MPa or at a pressure of 70MPa-120MPa. The tensile modulus of the PBF / PBBf blend or the copolymer of BF and BBf is in the range of 1GPa-4GPa or 2GPa-4GPa, and the maximum tensile strength is in the range of 20MPa-90MPa or 40MPa-90MPa.

[0104] Example VII: Injection Molding Process for PBF / PBBf Blends or Copolymers of BF and BBf with Additives

[0105] The blend of PBF and PBBf or the copolymer of BF and BBf can be compounded with a variety of additives. The additives may include, but are not limited to, glass fiber, carbon fiber, talc or natural fillers. 1 wt%-60 wt% of such additives may be added for mechanical reinforcement. As a flame retardant, 1 wt%-40 wt% of a flame retardant such as a phosphate ether, magnesium hydroxide or aluminum diethylphosphinate may be added. 0.1 wt%-10 wt% of a hindered phenol, thioether, phosphite or combination may be added as an antioxidant. 0.1 wt%-10 wt% of an acid scavenger may be added as an anti-hydrolysis agent. 0.1 wt%-10 wt% of benzotriazole, hydroxybenzophenone may be added as a UV stabilizer. Color pigments may be added at ≤20 wt% as needed. 0.02% to 5% of a color-changing additive for laser engraving may be added. Other additives may be added as needed: lubricants (such as polytetrafluoroethylene (PTFE)), esters and metal salts of fatty acids (such as zinc stearate, calcium stearate and AAGP), nucleating agents (such as sodium benzoate, sodium salt of saccharin, boron nitride, organic acids, metal salts, inorganic substances (such as CNT, talc, glass fibers or metal carbonates), and coupling agents and waxes (such as ethylene bisstearamide).

[0106] Using an injection molding device (e.g. Figure 3 The molding machine 300 in the embodiment of the present invention is used to inject the compounded blend of PBF and PBBf or the synthetic copolymer of BF and BBf to form an electrical connector or an electrical housing (e.g., such as Figures 1 to 2B Those described). Prior to injection molding, the composite material based on the blend or copolymer is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours. In this embodiment, the moisture content during drying is less than 0.2% or less than 0.03%. The compounded blend or copolyester pellets containing additives are heated to about 180°C to 280°C, and then the melt is injected into a mold maintained at a temperature between 40°C and 120°C or 60°C to 110°C at a pressure of 50MPa-220MPa or at a pressure of 90MPa-150MPa. In the selected injection molding temperature and load range, the intrinsic viscosity (IV) is between 0.5dL / g and 1.5dL / g, and the melt flow index is between 5g / 10 minutes and 70g / 10 minutes. The tensile modulus of the composites of PBF and the reinforcing additives is in the range of 3 GPa-7 GPa, or in the range of 5 GPa-7 GPa, and the maximum tensile strength is in the range of 50 MPa-150 MPa, or in the range of 90 MPa-150 MPa.

[0107] Example VIII: Injection Molding Process for PBF-PEF Blends or Copolymers of BF and EF

[0108] As previously mentioned, PBF has a melting temperature of about 168°C to 186°C, and PEF has a melting temperature of 202°C to 220°C. Therefore, for some applications, it is necessary to blend PBF and PEF or synthesize a random copolymer (e.g., copolyester) of butylene furanoate (BF) and ethylene furanoate (EF). Depending on the weight % of BF in the blend or copolymer, the melting temperature may be in the range of 168°C to 220°C. In this embodiment, an injection molding device (e.g., Figure 3 The molding machine 300 in the embodiment of the present invention is used to inject a blend of PBF and PEF or a copolymer of BF and EF to form an electrical connector or an electrical housing (e.g., such as Figures 1 to 2B Those described). Before injection molding, the compounded pellets including the blend of PBF and PEF or the copolymer of BF and EF are air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours. The moisture content during drying is less than 0.2% or less than 0.03%. The blend or copolymer is heated between 180°C and 280°C and then injection molded into a mold maintained at a temperature between 40°C and 120°C or between 60°C and 80°C at a pressure of 50MPa-180MPa or at a pressure of 70MPa-120MPa. The tensile modulus of the PBF / PEF blend or the copolymer of BF and BBf is in the range of 1GPa-4GPa or 2GPa-4GPa, and the maximum tensile strength is in the range of 20MPa-95MPa or 40MPa-95MPa.

[0109] Example IX: Injection molding process for blends of PBF and PEF or copolymers of BF and EF with additives

[0110] The blend of PBF and PEF or the copolymer of BF and EF can be compounded with a variety of additives. The additives may include, but are not limited to, glass fiber, carbon fiber, talc or natural fillers. 1 wt%-60 wt% of such additives can be added for mechanical reinforcement. As a flame retardant, 1 wt%-40 wt% of a flame retardant such as a phosphate ether, magnesium hydroxide or aluminum diethylphosphinate can be added. 0.1 wt%-10 wt% of a hindered phenol, a thioether, a phosphite or a combination can be added as an antioxidant. 0.1 wt%-10 wt% of an acid scavenger can be added as an anti-hydrolysis agent. 0.1 wt%-10 wt% of benzotriazole, hydroxybenzophenone can be added as a UV stabilizer. Color pigments can be added at ≤20 wt% as needed. 0.02% to 5% of a color-changing additive for laser engraving can be added. Other additives may be added as needed: lubricants such as polytetrafluoroethylene (PTFE), esters and metal salts of fatty acids such as zinc stearate, calcium stearate and AAGP, nucleating agents such as sodium benzoate, sodium salt of saccharin, boron nitride, organic acids, metal salts, inorganic substances such as CNT, talc or metal carbonates, as well as coupling agents and waxes such as ethylene bisstearamide.

[0111] Using an injection molding device (e.g. Figure 3 The molding machine 300 in the embodiment of the present invention is used to inject the compounded blend of PBF and PEF or the synthetic copolymer of BF and EF to form an electrical connector or electrical housing (e.g., such as Figures 1 to 2B Those described). Prior to injection molding, the composite material based on the blend or copolymer is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours. In this embodiment, the moisture content during drying is less than 0.2% or less than 0.03%. The compounded blend or copolyester pellets containing additives are heated to about 180°C to 280°C, and then the melt is injected into a mold maintained at a temperature between 40°C and 120°C or 60°C to 110°C at a pressure of 50MPa-220MPa or at a pressure of 90MPa-150MPa. In the selected injection molding temperature and load range, the intrinsic viscosity (IV) is between 0.5dL / g and 1.5dL / g, and the melt flow index is between 5g / 10 minutes and 70g / 10 minutes. The tensile modulus of the composites of PBF and the reinforcing additives is in the range of 3 GPa-7 GPa, or in the range of 5 GPa-7 GPa, and the maximum tensile strength is in the range of 50 MPa-150 MPa, or in the range of 90 MPa-150 MPa.

[0112] Example X: Compounding of PBF

[0113] Compounding of PBF and additives

[0114] As mentioned above, PBF has a melting temperature of about 168° C. to 186° C. In order to improve the durability and processability of PBF in practical applications, PBF may be mixed with additives such as antioxidants, UV stabilizers, flame retardants, anti-hydrolysis agents, color pigments, lubricants, waxes, nucleating agents, color-changing additives for laser engraving, etc. to obtain extrusion pellets.

[0115] In this embodiment, the PBF is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours before extrusion. The additives are dried as needed. The moisture content during drying is less than 0.2% or less than 0.03%. The PBF pellets and additives are melt-mixed between 180°C and 230°C or between 190°C and 210°C. The components are fed together or separately along the extruder using the side feed of the extruder. Extrusion is carried out using a twin-screw or single-screw extruder. Generally speaking, a twin-screw extruder can be more shear-intensive than a single-screw extruder. Optionally, the extruded composition is granulated and dried to obtain dry pellets for injection molding. The moisture content in the dry pellets is less than 0.2% or less than 0.03%.

[0116] Compounding of PBF with fillers and / or additives

[0117] For practical applications, PBF can be compounded with various fillers and additives as discussed above (Example II). In this embodiment, PBF is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours before extrusion. The moisture content during drying is less than 0.2% or less than 0.03%. PBF pellets and fillers (such as glass fiber, carbon fiber, talcum powder or natural fillers and / or other additives) are melt-mixed between 180°C and 230°C or between 190°C and 210°C. Each component can be fed together or separately along the extruder. The reinforcing additives are fed separately using a side feeder to avoid the wear of the reinforcing additives. In a low shear single-screw extruder, the filler or additive is mixed with the polymer and fed together through the main feeder of the extruder. In a high shear twin-screw extruder, the filler or additive can be mixed with the polymer or fed separately through the main side feeder of the extruder. Extrusion is carried out using a twin-screw or single-screw extruder. Optionally, the extruded composition is granulated and dried to obtain dry pellets for injection molding. The moisture content in the dried pellets is less than 0.2%, preferably < 0.03%.

[0118] Compounding PBF and PBT blends

[0119] In this embodiment, PBF is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours before extrusion. PBT is air-dried or vacuum-dried at between 80°C and 120°C for 4 to 8 hours before extrusion. The moisture content in both PBF and PBT during drying is 0.2%, or less than 0.03%. PBF and PBT pellets and additives are melt-mixed in an extruder. PBF and PBT are fed together into an extruder and melt-mixed under shear to obtain a PBT / PBF blend. The amount of PBT varies in the range of 1 wt%-99 wt%, or 1 wt%-20 wt% (e.g., 1 wt%-10 wt%, or 10 wt%-20 wt%), or 20 wt%-40 wt% (e.g., 20 wt%-30 wt%, or 30 wt%-40 wt%), or 40 wt%-60 wt% (e.g., 40 wt%-50 wt% or 50 wt%-60 wt%), or 60 wt%-80 wt% (e.g., 60 wt%-70 wt% or 70 wt%-80 wt%), or 80 wt%-99 wt% (80 wt%-90 wt%, or 90 wt%-99 wt%). The extruder temperature is in the range of 180°C to 250°C, wherein the extruder temperature is determined by the melt temperature of the PBF / PBT blend, which in turn depends on the PBF / PBT mixing ratio. Extrusion is performed using a twin-screw or single-screw extruder. The extruder screw speed is between 30 rpm and 200 rpm, or ≤ 100 rpm. The extruded composition is optionally pelletized and air-dried or vacuum-dried to obtain dry pellets for injection molding. The moisture content in the dry pellets is less than 0.2%, or < 0.03%.

[0120] Compounding of PBBf and additives

[0121] As mentioned above, PBBf has a melting temperature of about 215° C. to 217° C. In order to improve the durability and processability of PBBf in practical applications, PBBf may be mixed with additives such as antioxidants, UV stabilizers, flame retardants, anti-hydrolysis agents, color pigments, lubricants, waxes, nucleating agents, color-changing additives for laser engraving, etc. to obtain extrusion pellets.

[0122] In this embodiment, before extrusion, PBBf is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours. Additives are optionally dried as needed. The moisture content during drying is less than 0.2% or less than 0.03%. PBBf pellets and additives are melt-mixed between 220°C and 280°C or between 230°C and 260°C. The mixture is fed together along the extruder. Alternatively, PBBf pellets and additives are fed separately along the extruder. Extrusion is carried out using a twin-screw or single-screw extruder. The extruder screw speed varies from 30rpm to 200rpm, or ≤100rpm. Optionally, the extruded composition is granulated and air-dried or vacuum-dried to obtain dry pellets for injection molding. The moisture content in the dry pellets is less than 0.2%, or <0.03%.

[0123] Compounding of PBBf with fillers and / or additives

[0124] For practical applications, PBBf can be compounded with various fillers and additives as discussed in Example V above. In this embodiment, PBBf is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours before extrusion. The moisture content during drying is less than 0.2% or less than 0.03%. PBBf pellets and fillers (such as glass fiber, carbon fiber, talcum powder or natural fillers and / or other additives) are melt-mixed between 220°C and 280°C or between 230°C and 260°C. The individual components are fed together or separately along the extruder. Preferably, the fillers are fed separately using a side feeder. Extrusion is carried out using a twin-screw or single-screw extruder. Optionally, the extruded composition is granulated and dried to obtain pellets for injection molding. The moisture content in the dried pellets is less than 0.2%, preferably <0.03%.

[0125] Blends of PBF and PBBf

[0126] In this embodiment, PBF and PBBf are air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours before extrusion. The moisture content in PBF and PBBf during drying is less than 0.2%, or less than 0.03%. PBF, PBBf and additives are fed into an extruder together and melt-mixed under shear to obtain a PBF / PBBf blend. Fillers (such as glass fiber, carbon fiber, talc or natural filler) and / or additives are added together with PBF and PBBf or added separately along the extruder. The amount of PBF varies in the range of 1 wt%-99 wt%, or 1 wt%-20 wt% (e.g., 1 wt%-10 wt%, or 10 wt%-20 wt%), or 20 wt%-40 wt% (e.g., 20 wt%-30 wt%, or 30 wt%-40 wt%), or 40 wt%-60 wt% (e.g., 40 wt%-50 wt% or 50 wt%-60 wt%), or 60 wt%-80 wt% (e.g., 60 wt%-70 wt% or 70 wt%-80 wt%), or 80 wt%-99 wt% (80 wt%-90 wt%, or 90 wt%-99 wt%). The composition of the filler varies from 1 wt%-60 wt%. The extruder temperature is in the range of 180°C to 280°C, the preferred extruder temperature being determined by the melting temperature of the PBF / PBBf blend and set slightly above the melting temperature, which in turn depends on the PBF / PBBf mixing ratio or the BF to BBf ratio in the BF / BBf copolyester. Extrusion is carried out using a twin-screw or single-screw extruder. The extruder screw speed varies from 30 rpm to 200 rpm, or ≤100 rpm. The extruded composition is optionally pelletized and dried to obtain dry pellets for injection molding. The moisture content in the dry pellets is less than 0.2%, preferably <0.03%.

[0127] Compounding of PBF / PBBf blends or copolymers of BF and BBf with additives

[0128] The PBF / PBBf blend or copolymer of BF and BBf can be compounded with various additives (e.g., fillers) as discussed in Examples II and V above. In this embodiment, the PBF, PBBf, or copolymer of BF and BBf is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours prior to extrusion. The moisture content during drying is less than 0.2% or less than 0.03%. The polymer, copolymer and / or one or more fillers (such as glass fiber, carbon fiber, talc, natural filler) and / or other additives are melt-mixed between 180°C and 280°C, and the preferred extruder temperature is determined by the melting temperature of the PBF / PBBf blend and is set slightly above the melting temperature, which depends on the PBF / PBBf mixing ratio or the BF to BBf ratio in the BF / BBf copolyester. The individual components are fed together or separately along the extruder. Preferably, the filler is fed separately using a side feeder. Extrusion is carried out using a twin-screw or single-screw extruder. The extruder screw speed varies from 30 rpm to 200 rpm, or ≤ 100 rpm. The extruded composition is optionally pelletized and dried to obtain dry pellets for injection molding. The moisture content in the dry pellets is less than 0.2%, or < 0.03%.

[0129] Blends of PBF and PEF

[0130] In this embodiment, the PBF and PEF are air-dried or vacuum-dried at 80° C. to 120° C. for 4 to 8 hours before extrusion. The moisture content in the PBF and PEF during drying is less than 0.2%, or less than 0.03%. The PBF, PEF and additives are fed into an extruder together and melt-mixed under shear to obtain a PBF / PEF blend. Fillers (such as glass fiber, carbon fiber, talc or natural filler) and / or additives are added together with the PBF and PEF or added separately along the extruder. The amount of PBF varies in the range of 1 wt%-99 wt%, or 1 wt%-20 wt% (e.g., 1 wt%-10 wt%, or 10 wt%-20 wt%), or 20 wt%-40 wt% (e.g., 20 wt%-30 wt%, or 30 wt%-40 wt%), or 40 wt%-60 wt% (e.g., 40 wt%-50 wt% or 50 wt%-60 wt%), or 60 wt%-80 wt% (e.g., 60 wt%-70 wt% or 70 wt%-80 wt%), or 80 wt%-99 wt% (80 wt%-90 wt%, or 90 wt%-99 wt%). The composition of the filler varies from 1 wt%-60 wt%. The extruder temperature ranges from 180°C to 280°C, and the preferred extruder temperature is determined by the melting temperature of the PBF / PEF blend and is set slightly above the melting temperature. Extrusion is carried out using a twin-screw or single-screw extruder. The extruder screw speed varies from 30 rpm to 200 rpm, or ≤ 100 rpm. The extruded composition is optionally granulated and dried to obtain dry pellets for injection molding. The moisture content in the dry pellets is less than 0.2%, preferably < 0.03%.

[0131] Compounding of PBF / PEF blends or copolymers of BF and EF with additives

[0132] The PBF / PEF blend or the copolymer of BF and EF can be compounded with various additives (e.g., fillers) as discussed in Examples (VIII) and (IX) above. In this embodiment, the PBF, PEF or copolymer of BF and EF is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours before extrusion. The moisture content during drying is less than 0.2% or less than 0.03%. The polymer, copolymer and / or one or more fillers (such as glass fiber, carbon fiber, talcum powder, natural filler) and / or other additives are melt-mixed between 180°C and 280°C, and the preferred extruder temperature is determined by the melting temperature of the PBF / PBBf blend and is set to be slightly higher than the melting temperature, which depends on the PBF / PEF mixing ratio or the BF to EF ratio in the BF / EF copolyester. The individual components are fed together or separately along the extruder. Preferably, the filler is fed separately using a side feeder. Extrusion is carried out using a twin-screw or single-screw extruder. The extruder screw speed varies from 30 rpm to 200 rpm, or ≤ 100 rpm. The extruded composition is optionally pelletized and dried to obtain dry pellets for injection molding. The moisture content in the dry pellets is less than 0.2%, or < 0.03%.

[0133] Remark

[0134] The above description and accompanying drawings are illustrative and should not be construed as limiting. Many specific details are described to provide a thorough understanding of the present disclosure. However, in some cases, well-known details are not described to avoid obscuring the description. In addition, various modifications may be made without departing from the scope of the embodiments.

[0135] The terms used in this specification generally have their ordinary meaning in the art within the context of this disclosure and in the specific context in which each term is used. It should be understood that the same thing can be described in more than one way. For example, people will recognize that "resin" is a form of "polymer" and these terms are sometimes used interchangeably.

[0136] Unless otherwise indicated, generally speaking, the term "about" is intended to encompass a variation or range of ±10%.

[0137] Examples used anywhere in this specification, including examples of any term discussed herein, are illustrative only and are not intended to further limit the scope and meaning of the disclosure or any exemplary term. Likewise, the disclosure is not limited to the various embodiments given in this specification.

[0138] PBF has a melting temperature of about 168° C. to 186° C. In this embodiment, an injection molding device (e.g., Figure 3The molding machine 300 in the embodiment of the present invention is used to inject PBF resin to form a keycap. Prior to injection molding, the PBF resin is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours. The moisture content of the environment during drying is less than 0.2% or less than 0.03%. The PBF pellets are heated to a melt (melt refers to a material in a molten state) at an injection molding machine barrel temperature of about 180°C to 230°C or about 190°C to 210°C before injection. The melt is introduced into a mold maintained at a temperature between 40°C and 100°C or at a temperature between 60°C and 80°C at an injection pressure of 50MPa-180MPa or at an injection pressure of 70MPa-120MPa. Within the selected injection molding temperature and load range, the intrinsic viscosity (IV) is between 0.5dL / g and 1.5dL / g, and the melt flow index is between 5g / 10min and 70g / 10min.

[0139] The tensile modulus of the PBF is in the range of 1 GPa-4 GPa or 2 GPa-4 GPa, and the maximum tensile strength is in the range of 20 MPa-70 MPa or 40 MPa-70 MPa. The properties of the PBF samples are further improved by annealing the molded samples at 60° C.-135° C., preferably at 115° C. Annealing increases the crystallinity of the keycap, thereby improving its strength and durability.

[0140] PBF can be synthesized as described in Papageorgiou et al., “Evaluation of polyesters from renewable resources as alternatives to the current fossil-based polymers. Phase transitions of poly(butylene 2,5-furan-dicarboxylate)”, Polymer 55, 3846 (2014) or JC Morales-Huerta et al., “Poly(alkylene 2,5-furandicarboxylate)s (PEF and PBF) by ring opening”, Polymer 87, 148 (2016).

[0141] Example II: Injection Molding Process for PBF Compounded with Additives

[0142] For practical applications, the PBF resin can be compounded with a variety of additives (see Example VIII for compounding). For example, 1 wt% to 60 wt% of one or more additives (including glass fiber, carbon fiber, talc or natural fillers) can be added for mechanical reinforcement. Natural fillers refer to plant-based filler materials derived from plants (grasses, shrubs, trees, etc.). Natural fillers can include, but are not limited to, cellulose, bamboo, cork, hardwood, flax, kenaf, jute, ramie, coconut husk fiber, kapok, sisal, henaquin fiber, abaca, hemp, bagasse, wheat straw, rice husk, rattan or Indian hemp fiber.

[0143] In this embodiment, 1 wt%-40 wt% of a flame retardant such as a phosphate ether, magnesium hydroxide or aluminum diethylphosphinate may be added. 0.1 wt%-10 wt% of a hindered phenol, thioether, phosphite or combination may be added as an antioxidant. 0.1 wt%-10 wt% of an acid scavenger may be added as an anti-hydrolysis agent. 0.1 wt%-10 wt% of benzotriazole, hydroxybenzophenone may be added as a UV stabilizer. Color pigments may be added at ≤20 wt% as needed. 0.02% to 5% of a color-changing additive for laser engraving may be added. Other additives may include lubricants such as polytetrafluoroethylene (PTFE), esters and metal salts of fatty acids such as zinc stearate, calcium stearate, and adipic acid glycol polyester (AAGP); nucleating agents such as sodium benzoate, sodium salt of saccharin, boron nitride, organic acids, metal salts, inorganic substances such as CNTs, talc, glass fibers, or metal carbonates; and coupling agents and waxes such as ethylene bisstearamide.

[0144] Using an injection molding device (e.g., Figure 3 The molding machine 300 described herein is described to inject the compounded PBF composite pellets to form keycaps. Prior to injection molding, the PBF composite material is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours. The moisture content during drying is less than 0.2% or less than 0.03%. The PBF pellets are heated to about 180°C to 230°C or 190°C to 210°C, and then the melt is injected into a mold maintained at a temperature between 40°C and 100°C or between 60°C and 80°C at a pressure of 50MPa-220MPa or a pressure of 90MPa-150MPa. Within the selected injection molding temperature and load range, the intrinsic viscosity (IV) is between 0.5dL / g and 1.5dL / g, and the melt flow index is between 5g / 10 minutes and 70g / 10 minutes.

[0145] The tensile modulus of the composites of PBF and the reinforcing additives is in the range of 3 GPa-7 GPa, or in the range of 5 GPa-7 GPa, and the maximum tensile strength is in the range of 50 MPa-150 MPa, or in the range of 90 MPa-150 MPa.

[0146] Example III: Injection Molding Process for PBF / PBT Blends

[0147] As previously mentioned, PBF has a melting temperature of about 168°C to 186°C, while PBT has a melting point of about 221°C to 225°C. For applications that must have a higher melting temperature than pure PBF, it may be necessary to use a blend of PBF and PBT. The synthesis of such a blend is described by X. Zhang et al. in CN110229480A "A kind of preparation method of poly-furandicarboxylic acid butanediol ester and polybutyleneterephthalate (PBT) blend". The melting point of the blend varies depending on the ratio of PBF to PBT. For example, a 50 / 50 PBF / PBT blend will have a melting temperature close to 195°C to 200°C.

[0148] In this embodiment, an injection molding device as described above (e.g., Figure 3 The molding machine 300 in the embodiment of the present invention is used to inject a blend containing PBF and PBT to form a keycap. Prior to injection molding, the compounded PBF and PBT pellets are air-dried or vacuum-dried at 80° C. to 120° C. for 4 to 8 hours. In this embodiment, the moisture content during drying is less than 0.2% or less than 0.03%. The compounded PBF and PBT pellets are heated between 180° C. and 240° C. or between 190° C. and 220° C., and then injection molded into a mold maintained at a temperature between 40° C. and 120° C. or a temperature between 60° C. and 80° C. at a pressure of 50 MPa-150 MPa or at a pressure of 70 MPa-120 MPa.

[0149] In this embodiment, the tensile modulus of the PBF / PBT blend is in the range of 1 GPa-4 GPa or 2 GPa-4 GPa, and the maximum tensile strength is in the range of 20 MPa-70 MPa or 40 MPa-70 MPa. The heat deformation temperature of the blend is expected to be between 60°C and 150°C, or between 100°C and 150°C.

[0150] Example IV: Injection Molding Process and Properties of PBBf

[0151] As previously mentioned, PBBf has a melting temperature of about 215° C. to 217° C. In this example, an injection molding device (e.g., Figure 3The PBBf resin is injected into the injection molding machine 300 in the injection molding machine to form the key cap. Prior to injection molding, the PBBf resin is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours. The moisture content after drying is less than 0.2% or less than 0.03%. The PBBf pellets are heated to a barrel temperature of about 220°C to 280°C or between 230°C and 260°C of the injection molding machine, and then the melt is injected into a mold set at a temperature between 60°C and 120°C or a temperature between 80°C and 110°C at an injection pressure of 50MPa-180MPa or at an injection pressure of 70MPa-120MPa. Within the selected injection molding temperature and load range, the intrinsic viscosity (IV) is between 0.5dL / g and 1.5dL / g, and the melt flow index is between 5g / 10min and 70g / 10min.

[0152] The tensile modulus of PBBf is in the range of 1 GPa-4 GPa or 2 GPa-4 GPa, and the maximum tensile strength is in the range of 40 MPa-90 MPa or 55 MPa-90 MPa.

[0153] BFDCA (precursor of PBBf) can be synthesized as described in Mingchun Ye et al., “Oxidative coupling of 2-methylfuroate: A scalable synthesis of dimethyl2,2'-bifuran-5,5'-dicarboxylate”, Applied Catalysis A: General, 619, 118138 (2021), and PBBf can be synthesized from the precursor BFDCA as described in T. Kainulainen et al., “Utilizing Furfural-Based Bifuran Diester as Monomer and Comonomer for High-Performance Bioplastics: Properties of Poly(butylenefuranoate), Poly(butylene bifuranoate), and Their Copolyesters”, Biomacromolecules 21, 743 (2020).

[0154] Example V: Injection Molding Process of PBBf for Compounding with Additives

[0155] For practical applications, PBBf resin can be compounded with a variety of additives (including but not limited to glass fiber, carbon fiber, talc or natural filler). 1 wt%-60 wt% of such additives can be added for mechanical reinforcement. 1 wt%-40 wt% of flame retardants such as phosphate ethers, magnesium hydroxide or diethyl phosphinate aluminum can be added. 0.1 wt%-10 wt% of hindered phenols, thioethers, phosphites or any combination can be added as antioxidants. 0.1 wt%-10 wt% of acid scavengers can be added as anti-hydrolysis agents. 0.1 wt%-10 wt% of benzotriazole and hydroxybenzophenone can be added as UV stabilizers. Color pigments can be added as needed at ≤20 wt%. 0.02% to 5% of color-changing additives for laser engraving can be added. Other additives may be added as needed: lubricants (such as polytetrafluoroethylene (PTFE)), esters and metal salts of fatty acids (such as zinc stearate, calcium stearate and AAGP), nucleating agents (such as sodium benzoate, sodium salt of saccharin, boron nitride, organic acids, metal salts, inorganic substances (such as CNT, talc, glass fibers or metal carbonates), and coupling agents and waxes (such as ethylene bisstearamide).

[0156] In this embodiment, an injection molding device (e.g., Figure 3 The molding machine 300 in the injection molding machine 300) is used to inject the compounded PBBf composite pellets to form keycaps. Before injection molding, the PBBf composite material is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours. The moisture content after drying is less than 0.2% or less than 0.03%. The PBBf composite pellets are heated to a temperature of about 220°C to 280°C of the injection molding machine barrel temperature or a temperature between 230°C and 260°C, and then the melt is injected into a mold set at a temperature between 60°C and 120°C or between 80°C and 110°C at an injection pressure of 50MPa-220MPa or at an injection pressure of 90MPa-150MPa. Within the selected injection molding temperature and load range, the intrinsic viscosity (IV) is between 0.5dL / g and 1.5dL / g, and the melt flow index is between 5g / 10 and 70g / 10 minutes.

[0157] The tensile modulus of the PBBf-glass fiber composite is in the range of 3 GPa-7 GPa or 5 GPa-7 GPa, and the maximum tensile strength is in the range of 50 MPa-150 MPa or 90 MPa-150 MPa.

[0158] Example VI: Injection Molding Process for PBF-PBBf Blends and Copolymers of BF and BBf

[0159] As mentioned above, PBF has a melting temperature of about 168°C to 186°C, and PBBf has a melting point of 215°C to 217°C. Therefore, for some applications, it is necessary to blend PBF and PBBf or synthesize random copolymers (e.g., copolyesters) of furanic acid butylene ester (BF) and bisfuranic acid butylene glycol ester (BBf) derived from FDCA and BFDCA, respectively. The synthesis of random copolymers of BF and BBf is described in Kainulainen et al. "Utilizing Furfural-Based Bifuran Diester as Monomer and Comonomer for High-Performance Bioplastics: Properties of Poly (butylenefuranoate), Poly (butylene bifuranoate), and Their Copolymers", Biomacromolecules 21, 743-752 (2020).

[0160] Depending on the weight % of BF in the blend or copolymer, the melt temperature can range from 168°C to 217°C. In this embodiment, an injection molding device (e.g., Figure 3 The molding machine 300 in the embodiment of the present invention is used to inject a blend of PBF and PBBf or a copolymer of BF and BBf to form a keycap. Prior to injection molding, the compounded pellets including the blend of PBF and PBBf or the copolymer of BF and BBf are air-dried or vacuum-dried at 80° C. to 120° C. for 4 to 8 hours. The moisture content during drying is less than 0.2% or less than 0.03%. The blend or copolymer is heated between 180° C. and 280° C. and then injection molded into a mold maintained at a temperature between 40° C. and 120° C. or between 60° C. and 80° C. at a pressure of 50MPa-180MPa or at a pressure of 70MPa-120MPa. The tensile modulus of the PBF / PBBf blend or the copolymer of BF and BBf is in the range of 1GPa-4GPa or 2GPa-4GPa, and the maximum tensile strength is in the range of 20MPa-90MPa or 40MPa-90MPa.

[0161] Example VII: Injection Molding Process for Blends of PBF and PBBf or Copolymers of BF and BBf with Additives

[0162] The blend of PBF and PBBf or the copolymer of BF and BBf can be compounded with a variety of additives. The additives may include, but are not limited to, glass fiber, carbon fiber, talc or natural fillers. 1 wt%-60 wt% of such additives may be added for mechanical reinforcement. As a flame retardant, 1 wt%-40 wt% of a flame retardant such as a phosphate ether, magnesium hydroxide or aluminum diethylphosphinate may be added. 0.1 wt%-10 wt% of a hindered phenol, thioether, phosphite or combination may be added as an antioxidant. 0.1 wt%-10 wt% of an acid scavenger may be added as an anti-hydrolysis agent. 0.1 wt%-10 wt% of benzotriazole, hydroxybenzophenone may be added as a UV stabilizer. Color pigments may be added at ≤20 wt% as needed. 0.02% to 5% of a color-changing additive for laser engraving may be added. Other additives may be added as needed: lubricants (such as polytetrafluoroethylene (PTFE)), esters and metal salts of fatty acids (such as zinc stearate, calcium stearate and AAGP), nucleating agents (such as sodium benzoate, sodium salt of saccharin, boron nitride, organic acids, metal salts, inorganic substances (such as CNT, talc, glass fibers or metal carbonates), and coupling agents and waxes (such as ethylene bisstearamide).

[0163] Using an injection molding device (e.g. Figure 3 The molding machine 300 in the injection molding machine 300) is used to inject the compounded blend of PBF and PBBf or the synthetic copolymer of BF and BBf to form a keycap. Prior to injection molding, the composite material based on the blend or copolymer is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours. In this embodiment, the moisture content during drying is less than 0.2% or less than 0.03%. The compounded blend or copolyester pellets containing additives are heated to about 180°C to 280°C, and then the melt is injected into a mold at a temperature maintained between 40°C and 120°C or 60°C to 110°C at a pressure of 50MPa-220MPa or at a pressure of 90MPa-150MPa. Within the selected injection molding temperature and load range, the intrinsic viscosity (IV) is between 0.5dL / g and 1.5dL / g, and the melt flow index is between 5g / 10 minutes and 70g / 10 minutes. The tensile modulus of the composites of PBF and the reinforcing additives is in the range of 3 GPa-7 GPa, or in the range of 5 GPa-7 GPa, and the maximum tensile strength is in the range of 50 MPa-150 MPa, or in the range of 90 MPa-150 MPa.

[0164] Example VIII: Injection Molding Process for PBF-PEF Blends or Copolymers of BF and EF

[0165] As previously mentioned, PBF has a melting temperature of about 168°C to 186°C, and PEF has a melting temperature of 202°C to 220°C. Therefore, for some applications, it is necessary to blend PBF and PEF or synthesize a random copolymer (e.g., copolyester) of butylene furanoate (BF) and ethylene furanoate (EF). Depending on the weight % of BF in the blend or copolymer, the melting temperature may be in the range of 168°C to 220°C. In this embodiment, an injection molding device (e.g., Figure 3 The molding machine 300 in the embodiment of the present invention is used to inject a blend of PBF and PEF or a copolymer of BF and EF to form a key cap (for example, referring to Figure 1 2C). Before injection molding, the compounded pellets including the blend of PBF and PEF or the copolymer of BF and EF are air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours. The moisture content during drying is less than 0.2% or less than 0.03%. The blend or copolymer is heated between 180°C and 280°C and then injection molded into a mold maintained at a temperature between 40°C and 120°C or between 60°C and 80°C at a pressure of 50MPa-180MPa or at a pressure of 70MPa-120MPa. The tensile modulus of the PBF / PEF blend or the copolymer of BF and BBf is in the range of 1GPa-4GPa or 2GPa-4GPa, and the maximum tensile strength is in the range of 20MPa-95MPa or 40MPa-95MPa.

[0166] Example IX: Injection molding process for blends of PBF and PEF or copolymers of BF and EF with additives

[0167] The blend of PBF and PEF or the copolymer of BF and EF can be compounded with a variety of additives. The additives may include, but are not limited to, glass fiber, carbon fiber, talc or natural fillers. 1 wt%-60 wt% of such additives can be added for mechanical reinforcement. As a flame retardant, 1 wt%-40 wt% of a flame retardant such as a phosphate ether, magnesium hydroxide or aluminum diethylphosphinate can be added. 0.1 wt%-10 wt% of a hindered phenol, a thioether, a phosphite or a combination can be added as an antioxidant. 0.1 wt%-10 wt% of an acid scavenger can be added as an anti-hydrolysis agent. 0.1 wt%-10 wt% of benzotriazole, hydroxybenzophenone can be added as a UV stabilizer. Color pigments can be added at ≤20 wt% as needed. 0.02% to 5% of a color-changing additive for laser engraving can be added. Other additives may be added as needed: lubricants such as polytetrafluoroethylene (PTFE), esters and metal salts of fatty acids such as zinc stearate, calcium stearate and AAGP, nucleating agents such as sodium benzoate, sodium salt of saccharin, boron nitride, organic acids, metal salts, inorganic substances such as CNT, talc or metal carbonates, as well as coupling agents and waxes such as ethylene bisstearamide.

[0168] Using an injection molding device (e.g. Figure 3 The molding machine 300 in the embodiment of the present invention is used to inject the compounded blend of PBF and PEF or the synthetic copolymer of BF and EF to form a key cap (for example, referring to Figure 1 2C). Prior to injection molding, the composite material based on the blend or copolymer is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours. In this embodiment, the moisture content during drying is less than 0.2% or less than 0.03%. The blend or copolyester pellets containing the additives are heated to about 180°C to 280°C, and then the melt is injected into a mold at a temperature of 40°C to 120°C or 60°C to 110°C at a pressure of 50MPa-220MPa or at a pressure of 90MPa-150MPa. In the selected injection molding temperature and load range, the intrinsic viscosity (IV) is between 0.5dL / g and 1.5dL / g, and the melt flow index is between 5g / 10 minutes and 70g / 10 minutes. The tensile modulus of the composites of PBF and the reinforcing additives is in the range of 3 GPa-7 GPa, or in the range of 5 GPa-7 GPa, and the maximum tensile strength is in the range of 50 MPa-150 MPa, or in the range of 90 MPa-150 MPa.

[0169] Example X: Compounding of PBF

[0170] Compounding of PBF and additives

[0171] As mentioned above, PBF has a melting temperature of about 168° C. to 186° C. In order to improve the durability and processability of PBF in practical applications, PBF may be mixed with additives such as antioxidants, UV stabilizers, flame retardants, anti-hydrolysis agents, color pigments, lubricants, waxes, nucleating agents, color-changing additives for laser engraving, etc. to obtain extrusion pellets.

[0172] In this embodiment, the PBF is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours before extrusion. The additives are dried as needed. The moisture content during drying is less than 0.2% or less than 0.03%. The PBF pellets and additives are melt-mixed between 180°C and 230°C or between 190°C and 210°C. The components are fed together or separately along the extruder using the side feed of the extruder. Extrusion is carried out using a twin-screw or single-screw extruder. Generally speaking, a twin-screw extruder can be more shear-intensive than a single-screw extruder. Optionally, the extruded composition is granulated and dried to obtain dry pellets for injection molding. The moisture content in the dry pellets is less than 0.2% or less than 0.03%.

[0173] Compounding of PBF with fillers and / or additives

[0174] For practical applications, PBF can be compounded with various fillers and additives as discussed above (Example II). In this embodiment, PBF is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours before extrusion. The moisture content during drying is less than 0.2% or less than 0.03%. PBF pellets and fillers (such as glass fiber, carbon fiber, talcum powder or natural fillers and / or other additives) are melt-mixed between 180°C and 230°C or between 190°C and 210°C. Each component can be fed together or separately along the extruder. The reinforcing additives are fed separately using a side feeder to avoid the wear of the reinforcing additives. In a low shear single-screw extruder, the filler or additive is mixed with the polymer and fed together through the main feeder of the extruder. In a high shear twin-screw extruder, the filler or additive can be mixed with the polymer or fed separately through the main side feeder of the extruder. Extrusion is carried out using a twin-screw or single-screw extruder. Optionally, the extruded composition is granulated and dried to obtain dry pellets for injection molding. The moisture content in the dried pellets is less than 0.2%, preferably < 0.03%.

[0175] Compounding PBF and PBT blends

[0176] In this embodiment, PBF is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours before extrusion. PBT is air-dried or vacuum-dried at between 80°C and 120°C for 4 to 8 hours before extrusion. The moisture content in both PBF and PBT during drying is 0.2%, or less than 0.03%. PBF and PBT pellets and additives are melt-mixed in an extruder. PBF and PBT are fed together into an extruder and melt-mixed under shear to obtain a PBT / PBF blend. The amount of PBT varies in the range of 1 wt%-99 wt%, or 1 wt%-20 wt% (e.g., 1 wt%-10 wt%, or 10 wt%-20 wt%), or 20 wt%-40 wt% (e.g., 20 wt%-30 wt%, or 30 wt%-40 wt%), or 40 wt%-60 wt% (e.g., 40 wt%-50 wt% or 50 wt%-60 wt%), or 60 wt%-80 wt% (e.g., 60 wt%-70 wt% or 70 wt%-80 wt%), or 80 wt%-99 wt% (80 wt%-90 wt%, or 90 wt%-99 wt%). The extruder temperature is in the range of 180°C to 250°C, which is determined by the melt temperature of the PBF / PBT blend, which in turn depends on the PBF / PBT mixing ratio. Extrusion is performed using a twin-screw or single-screw extruder. The extruder screw speed is between 30 rpm and 200 rpm, or ≤ 100 rpm. The extruded composition is optionally pelletized and air-dried or vacuum-dried to obtain dry pellets for injection molding. The moisture content in the dry pellets is less than 0.2% or < 0.03%.

[0177] Compounding of PBBf and additives

[0178] As mentioned above, PBBf has a melting temperature of about 215° C. to 217° C. In order to improve the durability and processability of PBBf in practical applications, PBBf may be mixed with additives such as antioxidants, UV stabilizers, flame retardants, anti-hydrolysis agents, color pigments, lubricants, waxes, nucleating agents, color-changing additives for laser engraving, etc. to obtain extrusion pellets.

[0179] In this embodiment, before extrusion, PBBf is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours. Additives are optionally dried as needed. The moisture content during drying is less than 0.2% or less than 0.03%. PBBf pellets and additives are melt-mixed between 220°C and 280°C or between 230°C and 260°C. The mixture is fed together along the extruder. Alternatively, PBBf pellets and additives are fed separately along the extruder. Extrusion is carried out using a twin-screw or single-screw extruder. The extruder screw speed varies from 30rpm to 200rpm, or ≤100rpm. Optionally, the extruded composition is granulated and air-dried or vacuum-dried to obtain dry pellets for injection molding. The moisture content in the dry pellets is less than 0.2% or <0.03%.

[0180] Compounding of PBBf with fillers and / or additives

[0181] For practical applications, PBBf can be compounded with various fillers and additives as discussed in Example V above. In this embodiment, PBBf is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours before extrusion. The moisture content during drying is less than 0.2% or less than 0.03%. PBBf pellets and fillers (such as glass fiber, carbon fiber, talcum powder or natural fillers and / or other additives) are melt-mixed between 220°C and 280°C or between 230°C and 260°C. The individual components are fed together or separately along the extruder. Preferably, the fillers are fed separately using a side feeder. Extrusion is carried out using a twin-screw or single-screw extruder. Optionally, the extruded composition is granulated and dried to obtain pellets for injection molding. The moisture content in the dried pellets is less than 0.2%, preferably <0.03%.

[0182] Blends of PBF and PBBf

[0183] In this embodiment, PBF and PBBf are air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours before extrusion. The moisture content in PBF and PBBf during drying is less than 0.2%, or less than 0.03%. PBF, PBBf and additives are fed into an extruder together and melt-mixed under shear to obtain a PBF / PBBf blend. Fillers (such as glass fiber, carbon fiber, talc or natural filler) and / or additives are added together with PBF and PBBf or added separately along the extruder. The amount of PBF varies in the range of 1 wt%-99 wt%, or 1 wt%-20 wt% (e.g., 1 wt%-10 wt%, or 10 wt%-20 wt%), or 20 wt%-40 wt% (e.g., 20 wt%-30 wt%, or 30 wt%-40 wt%), or 40 wt%-60 wt% (e.g., 40 wt%-50 wt% or 50 wt%-60 wt%), or 60 wt%-80 wt% (e.g., 60 wt%-70 wt% or 70 wt%-80 wt%), or 80 wt%-99 wt% (80 wt%-90 wt%, or 90 wt%-99 wt%). The composition of the filler varies from 1 wt%-60 wt%. The extruder temperature is in the range of 180°C to 280°C, and the preferred extruder temperature is determined by the melting temperature of the PBF / PBBf blend and is set slightly above the melting temperature, which in turn depends on the PBF / PBBf mixing ratio or the BF to BBf ratio in the BF / BBf copolyester. Extrusion is carried out using a twin-screw or single-screw extruder. The extruder screw speed varies from 30 rpm to 200 rpm, or ≤100 rpm. The extruded composition is optionally granulated and dried to obtain dry pellets for injection molding. The moisture content in the dry pellets is less than 0.2%, preferably <0.03%.

[0184] Compounding of PBF / PBBf blends or copolymers of BF and BBf with additives

[0185] The PBF / PBBf blend or copolymer of BF and BBf can be compounded with various additives (e.g., fillers) as discussed in Examples II and V above. In this embodiment, the PBF, PBBf, or copolymer of BF and BBf is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours prior to extrusion. The moisture content during drying is less than 0.2% or less than 0.03%. The polymer, copolymer and / or one or more fillers (such as glass fiber, carbon fiber, talc, natural filler) and / or other additives are melt-mixed between 180°C and 280°C, and the preferred extruder temperature is determined by the melting temperature of the PBF / PBBf blend and is set slightly above the melting temperature, which depends on the PBF / PBBf mixing ratio or the BF to BBf ratio in the BF / BBf copolyester. The individual components are fed together or separately along the extruder. Preferably, the filler is fed separately using a side feeder. Extrusion is carried out using a twin-screw or single-screw extruder. The extruder screw speed varies from 30 rpm to 200 rpm, or ≤ 100 rpm. The extruded composition is optionally pelletized and dried to obtain dry pellets for injection molding. The moisture content in the dry pellets is less than 0.2% or < 0.03%.

[0186] Blends of PBF and PEF

[0187] In this embodiment, the PBF and PEF are air-dried or vacuum-dried at 80° C. to 120° C. for 4 to 8 hours before extrusion. The moisture content in the PBF and PEF during drying is less than 0.2%, or less than 0.03%. The PBF, PEF and additives are fed into an extruder together and melt-mixed under shear to obtain a PBF / PEF blend. Fillers (such as glass fiber, carbon fiber, talc or natural filler) and / or additives are added together with the PBF and PEF or added separately along the extruder. The amount of PBF varies in the range of 1 wt%-99 wt%, or 1 wt%-20 wt% (e.g., 1 wt%-10 wt%, or 10 wt%-20 wt%), or 20 wt%-40 wt% (e.g., 20 wt%-30 wt%, or 30 wt%-40 wt%), or 40 wt%-60 wt% (e.g., 40 wt%-50 wt% or 50 wt%-60 wt%), or 60 wt%-80 wt% (e.g., 60 wt%-70 wt% or 70 wt%-80 wt%), or 80 wt%-99 wt% (80 wt%-90 wt%, or 90 wt%-99 wt%). The composition of the filler varies from 1 wt%-60 wt%. The extruder temperature ranges from 180°C to 280°C, and the preferred extruder temperature is determined by the melting temperature of the PBF / PEF blend and is set slightly above the melting temperature. Extrusion is carried out using a twin-screw or single-screw extruder. The extruder screw speed varies from 30 rpm to 200 rpm, or ≤ 100 rpm. The extruded composition is optionally granulated and dried to obtain dry pellets for injection molding. The moisture content in the dry pellets is less than 0.2%, preferably < 0.03%.

[0188] Compounding of PBF / PEF blends or copolymers of BF and EF with additives

[0189] The PBF / PEF blend or the copolymer of BF and EF can be compounded with various additives (e.g., fillers) as discussed in Examples (VIII) and (IX) above. In this embodiment, the PBF, PEF or copolymer of BF and EF is air-dried or vacuum-dried at 80°C to 120°C for 4 to 8 hours before extrusion. The moisture content during drying is less than 0.2% or less than 0.03%. The polymer, copolymer and / or one or more fillers (such as glass fiber, carbon fiber, talcum powder, natural filler) and / or other additives are melt-mixed between 180°C and 280°C, and the preferred extruder temperature is determined by the melting temperature of the PBF / PBBf blend and is set to be slightly higher than the melting temperature, which depends on the PBF / PEF mixing ratio or the BF to EF ratio in the BF / EF copolyester. The individual components are fed together or separately along the extruder. Preferably, the filler is fed separately using a side feeder. Extrusion is carried out using a twin-screw or single-screw extruder. The extruder screw speed varies from 30 rpm to 200 rpm, or ≤ 100 rpm. The extruded composition is optionally pelletized and dried to obtain dry pellets for injection molding. The moisture content in the dry pellets is less than 0.2% or < 0.03%.

[0190] Remark

[0191] The above description and accompanying drawings are illustrative and should not be construed as limiting. Many specific details are described to provide a thorough understanding of the present disclosure. However, in some cases, well-known details are not described to avoid obscuring the description. In addition, various modifications may be made without departing from the scope of the embodiments.

[0192] The terms used in this specification generally have their ordinary meaning in the art within the context of this disclosure and in the specific context in which each term is used. It should be understood that the same thing can be described in more than one way. For example, people will recognize that "resin" is a form of "polymer" and these terms are sometimes used interchangeably.

[0193] Unless otherwise indicated, generally speaking, the term "about" is intended to encompass a variation or range of ±10%.

[0194] Examples used anywhere in this specification, including examples of any term discussed herein, are illustrative only and are not intended to further limit the scope and meaning of the disclosure or any exemplary term. Likewise, the disclosure is not limited to the various embodiments given in this specification.

Claims

1. An electrical connector, comprising: A housing comprising one or more materials selected from the group consisting of: Polymer of butylene 2,5-furandicarboxylate (PBF), Polymer of butylene bisfuranate (PBBf), A copolymer of (i) butylene 2,5-furandicarboxylate (BF) and (ii) butylene bisfuranate (BBf), A copolymer of (i) ethylene 2,5-furandicarboxylate (EF) and (ii) one or both of BF and BBf, and Copolymers of (i) butylene terephthalate (BT) and (ii) one or more of BF, BBf and EF; and Electrical contacts.

2. The electrical connector according to claim 1, wherein the housing is configured as a female socket, the female socket comprising: A cavity includes the electrical contact.

3. The electrical connector according to claim 1, wherein the housing is configured as a male plug, the male plug comprising: A protruding member includes the electrical contact.

4. The electrical connector according to any one of claims 1 to 3, wherein the housing comprises a PBF.

5. The electrical connector according to any one of claims 1 to 3, wherein the housing comprises PBBf.

6. The electrical connector according to any one of claims 1 to 3, wherein the housing comprises: Blends of PBF and PBBf, or Copolymer of BF and BBf.

7. The electrical connector of any one of claims 1 to 3, wherein the housing further comprises poly(butylene terephthalate) (PBT).

8. The electrical connector according to any one of claims 1 to 3, wherein the housing comprises: Blends of PBT and PBF, Blends of PBT and PBBf, or A copolymer of BT and BF, a copolymer of BT or BBf, or a copolymer of BT, BF and BBf.

9. The electrical connector of any one of claims 1 to 3, wherein the housing comprises poly(ethylene 2,5-furandicarboxylate) (PEF).

10. The electrical connector of claim 9, wherein the housing comprises: Blends of PEF and PBF, Blends of PEF and PBBf, or A copolymer of EF and BF, a copolymer of EF and BBf, or a copolymer of EF, BF and BBf.

11. The electrical connector according to any one of claims 1 to 3, wherein the housing further comprises: The additive is selected from the group consisting of antioxidants, ultraviolet (UV) stabilizers, flame retardants, anti-hydrolysis agents, color pigments, color-changing additives for laser engraving, lubricants, waxes, nucleating agents, and any combination thereof.

12. The electrical connector according to any one of claims 1 to 3, wherein the housing further comprises: A reinforcing additive selected from the group consisting of glass fiber, carbon fiber, talc, cellulose, bamboo, cork, hardwood, flax, kenaf, jute, ramie, coconut shell fiber, kapok, sisal, henna fiber, abaca, hemp, bagasse, wheat straw, rice husk, rattan, Indian hemp fiber, and any combination thereof.

13. The electrical connector of claim 12, wherein the housing comprises: 1 wt% to 60 wt% of said reinforcing additive.

14. A method of producing a compounded pellet, the method comprising the steps of: A composition comprising: (a) A polymer or copolymer comprising one or more materials selected from the group consisting of: Polymer of butylene 2,5-furandicarboxylate (PBF), Polymer of butylene bisfuranate (PBBf), Copolymer of butylene 2,5-furandicarboxylate (BF) and butylene bisfuranate (BBf), A copolymer of BF and ethylene 2,5-furandicarboxylate (EF), a copolymer of BBf and EF, or a copolymer of BF, BBf and EF, and Copolymers of butylene terephthalate (BT) and one or more of BF, BBf and EF; and (b) a first additive, wherein the first additive comprises an antioxidant, an ultraviolet (UV) stabilizer, a flame retardant, an anti-hydrolysis agent, a color pigment, a color-changing additive for laser engraving, a lubricant, a wax, a nucleating agent, or Any combination of these; and The solutionized composition is extruded to produce the compounded pellets.

15. The method of claim 14, wherein the composition further comprises: The second additive is selected from the following: glass fiber, carbon fiber, talc, cellulose, bamboo, cork, hardwood, flax, kenaf, jute, ramie, coconut shell fiber, kapok, sisal, Henaquin fiber, Manila hemp, hemp, bagasse, wheat straw, rice husk, rattan, Indian hemp fiber, or any combination thereof.

16. The method of claim 14, wherein: The composition further comprises a polymer of butylene terephthalate (PBT), and The method further comprises the following steps prior to extruding the solutionized composition to produce the compounded pellets: The PBT is mixed with the polymer or copolymer to form a blend of PBT and the polymer or copolymer.

17. The method of claim 14, wherein: The composition comprises PBF and PBBf; and The method further comprises the following steps prior to extruding the solutionized composition to produce the compounded pellets: The PBF and PBBf are mixed to form a blend of PBF and PBBf.

18. The method of claim 14, wherein: The composition comprises a polymer of ethylene 2,5-furandicarboxylate (PEF), and The method further comprises, prior to extruding the solutionized composition to produce the compounded pellets: The PEF is mixed with the polymer or copolymer to form a blend of the PEF and the polymer or copolymer.

19. A method for injection molding an electrical enclosure, the method comprising the following steps: Obtain one or more materials, the materials comprising: Polymer of butylene 2,5-furandicarboxylate (PBF), Polymer of butylene bisfuranate (PBBf), A copolymer of (i) butylene 2,5-furandicarboxylate (BF) and (ii) butylene bisfuranate (BBf), (i) a copolymer of ethylene 2,5-furandicarboxylate (EF) and (ii) one or both of BF and BBf, A copolymer of (i) butylene terephthalate (BT) and (ii) one or more of BF, BBf and EF, or Any combination of them; heating the one or more materials to a molten state; and The material is injected into a mold to form the electrical housing.

20. The method of claim 19, wherein the one or more materials include: Blends of PBF and PBBf, or Copolymer of BF and BBf.

21. The method of claim 19, wherein the one or more materials further comprises poly(butylene terephthalate) (PBT).

22. The method of claim 19, wherein the one or more materials include: Blends of PBT and PBF, Blends of PBT and PBBf, or A copolymer of BT and BF, a copolymer of BT and BBf, or a copolymer of BT, Bf and BBf.

23. The method of claim 19, wherein the one or more materials further comprises poly(ethylene 2,5-furandicarboxylate) (PEF).

24. The method of claim 19, wherein the one or more materials include: Blends of PEF and PBF, Blends of PEF and PBBf, or A copolymer of EF and BF, a copolymer of EF and BBf, or a copolymer of EF, BF and BBf.

25. The method of claim 19, wherein the one or more materials include: Blends of PBT and PEF, Copolymer of BT and EF, or A copolymer of BT, EF and BF, a copolymer of BT, EF and BBf, or a copolymer of BT, EF, BF and BBf.

26. The method of any one of claims 19 to 25, wherein the one or more materials further comprises: An additive, the additive corresponding to an antioxidant, an ultraviolet (UV) stabilizer, a flame retardant, an anti-hydrolysis agent, a color pigment, a color-changing additive for laser inscription, a lubricant, a wax, a nucleating agent, or any combination thereof.

27. The method of any one of claims 19 to 25, wherein the one or more materials further comprises: The reinforcing additive comprises the following: glass fiber, carbon fiber, talc, cellulose, bamboo, cork, hardwood, flax, kenaf, jute, ramie, coconut shell fiber, kapok, sisal, henaquin fiber, abaca, hemp, bagasse, wheat straw, rice husk, rattan, Indian hemp fiber, or any combination thereof.

28. The method according to any one of claims 19 to 27, further comprising the following steps before heating the one or more materials to a molten state: Solutionizing PBF, PBBf, a blend of PBF and PBBf, or a copolymer of BF and BBf; and The solutionized PBF, PBBf, blend of PBF and PBBf or copolymer of BF and BBf is extruded to produce compounded pellets.

29. The method according to any one of claims 19 to 27, further comprising the steps of: The formed electrical housing is annealed at 60° C. or above to increase crystallinity of the electrical housing.

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