Supported zinc dimolybdate hydroxide / silica complexes and uses thereof in polymer formulations

Abstract

This invention provides a process for producing supported zinc dimolybdate hydroxide / silicon dioxide complexes, comprising the steps of reacting a zinc compound (such as zinc oxide) with molybdenum trioxide in an aqueous system to form a reaction mixture and contacting the reaction mixture with silicon dioxide to form the supported zinc dimolybdate hydroxide / silicon dioxide complex. The resulting supported zinc dimolybdate hydroxide / silicon dioxide complexes contain silicon dioxide and zinc dimolybdate hydroxide in an amount ranging from 3 to 20 wt.% zinc, and generally, at least 80 wt.% of the zinc dimolybdate hydroxide is present in the form of Zn3Mo2O8(OH)2. These supported zinc dimolybdate hydroxide / silicon dioxide complexes are suitable for polymer compositions, such as PVC-based and epoxy-based formulations.

Description

[Technical Field]

[0001] This invention is generally directed to zinc dimolybdate hydroxide materials, and more specifically, to supported zinc dimolybdate hydroxide / silicon dioxide complexes that can be used in polymer compositions to improve flame retardancy and reduce abrasiveness. References to related applications

[0002] This application claims the benefit of U.S. Provisional Application Serial No. 63 / 192,634, filed on May 25, 2021, the disclosure of which is incorporated herein by reference in its entirety. [Previous Technology]

[0003] None. [Summary of the Invention]

[0004] This summary is provided to introduce, in a simplified form, the concept selection further described below in the embodiments. This summary is not intended to identify the required or essential features of the claimed subject matter. Nor is this summary intended to limit the scope of the claimed subject matter.

[0005] This document discloses and describes a process for producing a supported zinc dimolybdate hydroxide / silicon dioxide complex. One such process may include: (i) reacting a zinc compound (zinc oxide being an illustrative example) with molybdenum trioxide (MoO3) in an aqueous system to form a reaction mixture; and (ii) contacting (or slurrying) the reaction mixture with silicon dioxide to form the supported zinc dimolybdate hydroxide / silicon dioxide complex. Another process for producing the supported zinc dimolybdate hydroxide / silicon dioxide complex may include contacting (or slurrying) zinc dimolybdate hydroxide with silicon dioxide in an aqueous system to form the supported zinc dimolybdate hydroxide / silicon dioxide complex.

[0006] Supported zinc dimolybdate hydroxide / silicon dioxide complexes are also disclosed and described herein, and such complexes may comprise: (a) silicon dioxide; and (b) zinc dimolybdate hydroxide, which is present in an amount ranging from 3 to 20 wt.% zinc based on the total weight of the supported zinc dimolybdate hydroxide / silicon dioxide complexes. Generally, at least 80 wt.% of zinc dimolybdate hydroxide and typically 90 to 100 wt.% are present in the crystalline form Zn3Mo2O8(OH)2.

[0007] Polymer compositions are also provided herein, and such compositions may comprise either a polymer or any of the supported zinc dimolybdate hydroxide / silicon dioxide fusions disclosed herein (e.g., generated by any of the processes disclosed herein). The relative amounts of the polymer and the supported zinc dimolybdate hydroxide / silicon dioxide fusions in the composition are not particularly limited, nor are the polymer types particularly limited, although supported zinc dimolybdate hydroxide / silicon dioxide fusions are particularly suitable for PVC and epoxy formulations.

[0008] The foregoing description of the invention and the following embodiments are provided as examples and are merely illustrative. Therefore, the foregoing description of the invention and the following embodiments should not be considered limiting. In addition, features or variations other than those set forth herein may be provided. For example, certain variations may refer to various combinations and sub-combinations of features described in the embodiments.

Implementation Method

[0015] Definition

[0016] To more clearly define the terms used herein, the following definitions are provided. Unless otherwise indicated, the following definitions apply to this invention. If a term is used in this invention but is not specifically defined herein, the definition in the IUPAC Compendium of Chemical Terminology, 2nd Edition (1997) may apply, provided that such definition does not contradict any other disclosure or definition applied herein, or render any technical solution to which such definition is applied uncertain or infeasible. In the event of any conflict between any definition or usage provided by any document incorporated herein by reference and the definition or usage provided herein, the definition or usage provided herein shall prevail.

[0017] In this document, features of the subject matter are described such that different combinations of features can be conceived within a particular pattern. For each pattern and feature disclosed herein, whether a particular combination is explicitly described or not, all combinations are considered to be interchangeable without adversely affecting the design, composition, process, or method described herein. Therefore, unless otherwise expressly stated, any pattern or feature disclosed herein can be combined to describe an inventive design, composition, process, or method consistent with the present invention.

[0018] Unless otherwise stated, although the composition and method are described herein as “comprising” various components or steps, the composition and method may also “consist substantially of” various components or steps or “component of” various components or steps.

[0019] Unless otherwise specified, the terms "a / an" and "the" are intended to include plural alternatives, such as at least one.

[0020] Generally, element groups are indicated using the numbering mechanism specified in the version of the periodic table published in Chemical and Engineering News, 63(5), 27, 1985. In some cases, the common names assigned to element groups may be used to indicate the group; for example, alkali metals of Group 1 elements, alkaline earth metals of Group 2 elements, etc.

[0021] The term "contact" as used herein refers to materials or components that may be blended, mixed, slurried, dissolved, reacted, treated, compounded, or otherwise contacted or combined in some other manner or by any suitable method. Unless otherwise specified, materials or components may be contacted together in any order, in any manner, and for any duration.

[0022] Molybdenum trioxide (MoO3) is commonly referred to as molybdic trioxide, molybdenum oxide (VI), and molybdenum anhydride (or molybdate anhydride). As will be readily apparent to those skilled in the art, in (acidic) aqueous environments, molybdenum trioxide can form molybdic acid and other substances, such as hydrates and molybdates. Therefore, when the use of molybdenum trioxide in aqueous mixtures or systems is disclosed herein, this means that it encompasses any form of molybdenum material or complex present in an aqueous environment, whether it be molybdic acid, hydrate, molybdate, and the like, or combinations thereof.

[0023] Although any methods and materials similar to or equivalent to those described herein may be used in the practice or testing of this invention, typical methods and materials are described herein.

[0024] All disclosures and patents mentioned herein are incorporated herein by reference for the purpose of describing and disclosing, for example, the constructions and methods described in the disclosures, which may be used in conjunction with the present invention.

[0025] This invention discloses several types of scopes. When any type of scope is disclosed or claimed, it is intended to individually disclose or claim every possible number that the scope can reasonably encompass, including the endpoints of the scope and any sub-scopes and combinations thereof covered therein. As a representative example, the d50 particle size of silicon dioxide can be within certain ranges in various embodiments of this invention. By virtue of this invention, the d50 particle size can be in the range of 0.2 to 5 µm, and it is intended to state that d50 can be any particle size within this range and, for example, can be equal to 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, or 5 µm. In addition, the d50 particle size can be in any range or combination of 0.2 to 5 µm, such as 0.2 to 2.5 µm, 0.2 to 1 µm, or 0.25 to 0.8 µm, etc. Similarly, all other scopes revealed in this article should be interpreted in a similar manner to this example.

[0026] Generally, whether explicitly stated or not, quantity, size, formulation, parameter, range, or other quantity or characteristic is described as "about" or "approximately". Whether modified by the terms "about" or "approximately", the scope of the patent application includes equivalents of quantity or characteristic. Detailed Description of the Invention

[0027] This document discloses a supported zinc dimolybdate hydroxide / silicon dioxide complex mainly containing the crystalline form of Zn3Mo2O8(OH)2, a method for producing the supported zinc dimolybdate hydroxide / silicon dioxide complex, and polymer compositions and articles containing the supported zinc dimolybdate hydroxide / silicon dioxide complex. The process for producing the supported complex is also disclosed.

[0028] This document provides various processes for producing supported zinc dimolybdate hydroxide / silicon dioxide complexes. A first process may comprise (or substantially comprise) or comprise of: (i) reacting a zinc compound with molybdenum trioxide (MoO3) in an aqueous system to form a reaction mixture; and (ii) contacting (or slurrying) the reaction mixture with silicon dioxide to form a supported zinc dimolybdate hydroxide / silicon dioxide complex. A second process for producing supported zinc dimolybdate hydroxide / silicon dioxide complexes may comprise (or substantially comprise) or comprise of: contacting (or slurrying) zinc dimolybdate hydroxide with silicon dioxide in an aqueous system to form a supported zinc dimolybdate hydroxide / silicon dioxide complex.

[0029] Generally, the features of any of the processes disclosed herein (e.g., zinc compounds, molybdenum trioxide (MoO3), zinc dimolybdate hydroxide, silicon dioxide, aqueous systems, and the temperature and pressure conditions on which any step is performed, and others) are described independently herein, and these features may be combined in any combination to further describe the disclosed processes. Furthermore, unless otherwise stated, other process steps may be performed before, during, and / or after any of the steps listed in the disclosed processes. Additionally, any supported zinc dimolybdate hydroxide / silicon dioxide complexes produced according to any of the disclosed processes are within the scope of this invention and are covered herein.

[0030] Referring now to the first process, steps (i) and (ii) can be performed independently at temperatures typically ranging from 20°C to 95°C, such as 50°C to 95°C, 70°C to 95°C, 75°C to 90°C, or 80°C to 90°C, but are not limited thereto. In these and other variations, these temperature ranges are also intended to cover cases where steps (i) and / or (ii) are performed at a range of different temperatures rather than at a single fixed temperature within individual ranges. The pressure at which steps (i) and (ii) are performed is not specifically limited, but can be performed independently at high pressure (e.g., 5 psig to 100 psig), at atmospheric pressure, or at any suitable sub-atmospheric pressure. In some cases, steps (i) and (ii) are performed at atmospheric pressure, thereby eliminating the need for pressurized vessels and their associated costs and complexity. Independently, steps (i) and (ii) can be performed over a wide range of time periods, such as 15 min to 24 hr, 30 min to 12 hr, or 90 min to 6 hr, but are not limited to these time periods. Other suitable temperature, pressure, and time ranges will readily become apparent from the present invention.

[0031] In step (i), the zinc compound is reacted with molybdenum trioxide in an aqueous system to form a reaction mixture. Any suitable zinc compound can be used, such as zinc oxide, zinc chloride, or zinc nitrate and the like. Zinc oxide is typically used because it does not introduce other elements (such as halogens or nitrogen) into the process that may subsequently need to be removed. The zinc compound and molybdenum trioxide can typically be in a Zn:Mo molar ratio in the range of 1:1 to 2:1 based on the total amount of each reactant, regardless of the order of addition or contact of the reactants or the method of addition used. For example, molybdenum trioxide (e.g., a slurry in water) can be added slowly—at any suitable addition rate—to zinc oxide (e.g., an aqueous solution) over any suitable time period. As will be readily apparent to those skilled in the art, the Zn:Mo molar ratio can vary as the reaction proceeds; therefore, the disclosed molar ratio range covers any molar ratio encountered during the reaction in step (i) and the formation of the reaction mixture. In other embodiments of the present invention, the Zn:Mo ratio may be from 1.2:1 to 1.8:1, 1.3:1 to 1.7:1, or 1.4:1 to 1.6:1. For example, the Zn:Mo molar ratio may be a stoichiometric ratio of 1.5:1 (+ / - 10%), reflecting the resulting zinc dimolybdate hydroxide having the formula Zn3Mo2O8(OH)2.

[0032] In step (ii) of the first process, the reaction mixture (in an aqueous system) is contacted with (or slurried therewith) silicon dioxide to form a supported zinc dimolybdate hydroxide / silicon dioxide complex, while in the second process, zinc dimolybdate hydroxide is contacted with (or slurried therewith) silicon dioxide in an aqueous system to form a supported zinc dimolybdate hydroxide / silicon dioxide complex. In both processes, the aqueous system may contain water (or consist substantially of water or be composed of water). The pH of the aqueous system is not particularly limited, and as will be readily apparent to those skilled in the art, the pH of the aqueous system and the pH for forming the supported zinc dimolybdate hydroxide / silicon dioxide complex may vary as the reaction proceeds. Where necessary, the aqueous system may contain an acid or base to adjust the pH or control the pH within a certain range during the first and / or second processes.

[0033] Referring now to the second process, the supported zinc dimolybdate hydroxide / silicon dioxide complex can be formed at temperatures typically ranging from 15°C to 95°C, such as 15°C to 50°C or 20°C to 35°C, but not limited thereto. In these and other examples, these temperature ranges are also intended to cover the formation of the supported zinc dimolybdate hydroxide / silicon dioxide complex at a series of different temperatures rather than at a single fixed temperature within individual ranges. The pressure at which the supported zinc dimolybdate hydroxide / silicon dioxide complex is formed is not particularly limited, but can be at high pressure (e.g., 5 psig to 100 psig), at atmospheric pressure, or at any suitable sub-atmospheric pressure. In some cases, the supported zinc dimolybdate hydroxide / silicon dioxide complex is formed at atmospheric pressure, thereby eliminating the need for pressurized vessels and their associated costs and complexity. Generally, supported zinc dimolybdate hydroxide / silicon dioxide complexes can be formed over a wide range of time periods, such as 15 min to 24 hr, 30 min to 12 hr, or 2 hr to 6 hr, but are not limited to these time periods. Other suitable temperature, pressure, and time ranges will readily become apparent from the present invention.

[0034] Where appropriate, the first and second processes for producing the supported zinc dimolybdate hydroxide / silicon dioxide complex may further include a step of removing the supported zinc dimolybdate hydroxide / silicon dioxide complex from water using any suitable separation technique. For example, filtration or centrifugation, and combinations thereof, may be used.

[0035] Where appropriate, the first and second processes for producing the supported zinc dimolybdate hydroxide / silicon dioxide complex may further include a step of drying the supported zinc dimolybdate hydroxide / silicon dioxide complex using any suitable drying conditions. For example, a drying temperature in the range of 50°C to 200°C or 100°C to 150°C may be used, and drying may be carried out at atmospheric pressure or any suitable subatmospheric pressure, such as less than 150 Torr or less than 50 Torr.

[0036] Where necessary, the first and second processes for producing the supported zinc dimolybdate hydroxide / silicon dioxide complex may further include a step of depolymerizing the supported zinc dimolybdate hydroxide / silicon dioxide complex, and may further include a step of grinding the supported zinc dimolybdate hydroxide / silicon dioxide complex, or may utilize both the depolymerization step and the grinding step. Supported zinc dimolybdate hydroxide / silicon dioxide complex

[0037] Consistent with the present invention, the supported zinc dimolybdate hydroxide / silicon dioxide complex described herein (or the supported zinc dimolybdate hydroxide / silicon dioxide complex produced according to any of the processes disclosed herein) can be used in a variety of polymer formulations having beneficial performance properties. In the present invention, the supported zinc dimolybdate hydroxide / silicon dioxide complex may comprise: (a) silicon dioxide; and (b) zinc dimolybdate hydroxide, which is present in an amount ranging from 3 to 20 wt.% zinc based on the total weight of the supported zinc dimolybdate hydroxide / silicon dioxide complex. At least 80 wt.% of the zinc dimolybdate hydroxide may be present in the crystalline form Zn3Mo2O8(OH)2.

[0038] The silicon dioxide component of the supported zinc dimolybdate hydroxide / silicon dioxide complex (or the silicon dioxide used in the process of producing the supported zinc dimolybdate hydroxide / silicon dioxide complex) typically has a median particle size (d50) in the range of 0.2 to 5 µm, 0.2 to 25 µm, 0.2 to 1 µm, or 0.25 to 0.8 µm. Alternatively or alternatively, the d100 particle size of the silicon dioxide may be in the range of 0.6 to 10 µm, 0.6 to 5 µm, 0.6 to 4 µm, 0.7 to 4 µm, or 0.7 to 3.5 µm. Alternatively or alternatively, the d10 particle size of the silicon dioxide may be in the range of 0.08 to 1 µm, 0.08 to 0.5 µm, 0.1 to 0.5 µm, or 0.1 to 0.4 µm. Alternatively or concurrently, silicon dioxide may be characterized by a BET surface area in the range of 2 to 20 m² / g, 4 to 15 m² / g, 4 to 12 m² / g, 5 to 15 m² / g, or 5 to 13 m² / g. Other suitable particle sizes and surface areas of silicon dioxide will readily become apparent from this invention.

[0039] While not limited thereto, in some embodiments of the present invention, the silica may be molten silica compared to fumed silica and precipitated silica. Generally, the silica is also spherical silica. Therefore, in certain embodiments, the silica component of the supported zinc dimolybdate hydroxide / silica complex (or the silica used in the process of producing the supported zinc dimolybdate hydroxide / silica complex) is spherical molten silica. If the average aspect ratio of the silica is in the range of 1:1 to 1.4:1, and more generally, the average aspect ratio is 1:1 to 1.25:1 or 1:1 to 1.1:1, it is considered spherical. Aspect ratio is defined herein as the longest (measurable) particle size divided by the shortest size when observed in a 2D SEM image (e.g., Figure 1). The average aspect ratio is the average of the aspect ratios of 10 (measurable) particles from the SEM image.

[0040] The supported zinc dimolybdate hydroxide / silicon dioxide complex described herein (or the supported zinc dimolybdate hydroxide / silicon dioxide complex produced by any of the processes described herein) may contain zinc dimolybdate hydroxide in an amount ranging from 3 to 20 wt.% zinc based on the total weight of the supported zinc dimolybdate hydroxide / silicon dioxide complex. In another state, the supported zinc dimolybdate hydroxide / silicon dioxide complex may contain 3 to 18 wt.% zinc, in another state 4 to 16 wt.% zinc, and in yet another state 5 to 15 wt.% zinc. Additionally or alternatively, the supported zinc dimolybdate hydroxide / silicon dioxide may contain 3 to 20 wt.% molybdenum, such as 3 to 18 wt.% molybdenum, 4 to 16 wt.% molybdenum, or 5 to 15 wt.% molybdenum.

[0041] Although not limited thereto, the supported zinc dimolybdate hydroxide / silicon dioxide wrought compounds described herein (or supported zinc dimolybdate hydroxide / silicon dioxide wrought compounds produced by any of the processes described herein) typically have a median particle size (d50) in the range of 0.3 to 6 µm, 0.3 to 2 µm, 0.4 to 1.8 µm, or 0.5 to 1.7 µm. Alternatively or alternatively, the d100 particle size of the supported zinc dimolybdate hydroxide / silicon dioxide wrought compounds may be in the range of 1 to 12 µm, 1 to 8 µm, 1.5 to 7 µm, 2 to 7 µm, or 2.5 to 6 µm. Alternatively or alternatively, the d10 particle size of the supported zinc dimolybdate hydroxide / silicon dioxide wrought compounds may be in the range of 0.1 to 1.5 µm, 0.1 to 0.8 µm, 0.1 to 0.7 µm, or 0.2 to 0.6 µm. Alternatively or alternatively, the span ((d90-d10) / d50) of the supported zinc dimolybdate hydroxide / silicon dioxide complex may be in the range of 1.5 to 5, 1.5 to 4.5, or 2 to 4. Alternatively or alternatively, the supported zinc dimolybdate hydroxide / silicon dioxide complex may be characterized by a BET surface area in the range of 3 to 20 m² / g, 3 to 15 m² / g, 3 to 12 m² / g, 4 to 13 m² / g, or 4 to 10 m² / g. Other suitable particle sizes and surface areas of the supported zinc dimolybdate hydroxide / silicon dioxide complex will readily become apparent from the present invention.

[0042] Similar to silicon dioxide, the supported zinc dimolybdate hydroxide / silicon dioxide complexes described herein (or supported zinc dimolybdate hydroxide / silicon dioxide complexes produced by any of the processes described herein) may be spherical (with an average aspect ratio in the range of 1:1 to 1.4:1, and more typically, an average aspect ratio in the range of 1:1 to 1.25:1 or 1:1 to 1.1:1).

[0043] In this document, at least 80 wt.% of zinc dimolybdate hydroxide may be present in the crystalline form Zn3Mo2O8(OH)2. For example, at least 80 wt.%, at least 85 wt.%, at least 90 wt.%, or at least 95 wt.% may be present as Zn3Mo2O8(OH)2. Therefore, substantially all (98 to 99.5 wt%) or all (100 wt%) of zinc dimolybdate hydroxide may be present in the crystalline form Zn3Mo2O8(OH)2. Other forms of zinc / molybdenum compounds include ZnMoO4·0.8 H2O and ZnMoO4 (zinc molybdate). Polymer composition

[0044] This invention also targets and covers any composition, formulation, complex, and article containing any of the supported zinc dimolybdate hydroxide / silicon dioxide complexes disclosed herein (and their respective properties or characteristics, such as surface area, particle size, amount of zinc, amount of molybdenum, crystal form, etc.). In a particular embodiment of the invention, a polymer composition is disclosed, wherein the polymer composition may comprise any suitable polymer (one or more) and any of the supported zinc dimolybdate hydroxide / silicon dioxide complexes disclosed herein (or supported zinc dimolybdate hydroxide / silicon dioxide complexes produced by any of the processes described herein).

[0045] In one sample, the polymer composition may contain a thermoplastic polymer, while in another sample, the polymer may contain a thermosetting polymer. In another sample, the polymer may contain, alone or in any combination, polyvinylidene chloride (PVDC), polyvinyl chloride (PVC), chlorinated polyvinyl chloride (CPVC), polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), and / or ethylene chlorotrifluoroethylene (ECTFE). In yet another sample, the polymer may contain plasticized or non-plasticized PVC. In yet another sample, the polymer may contain rigid PVC, or alternatively, the polymer may contain flexible PVC. Generally, rigid PVC may be referred to as non-plasticized PVC, while flexible PVC may be referred to as plasticized PVC.

[0046] As will be readily apparent to those skilled in the art, PVDC can be called polyvinylidene chloride and also poly(vinylidene chloride). Similarly, PVC can be called polyvinyl chloride and also poly(vinyl chloride).

[0047] In the sample, the polymer may contain epoxy resin. For example, the polymer may contain, alone or in any combination, bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, phenolic epoxy resin, cresol phenolic epoxy resin, bisphenol A phenolic epoxy resin, bisphenol F phenolic epoxy resin, stilbene epoxy resin, epoxy resin having a tri-framework, epoxy resin having a cyclopentadiene framework, triphenylmethane epoxy resin, biphenyl epoxy resin, xylene epoxy resin, biphenyl aralkyl epoxy resin, naphthalene epoxy resin, dicyclopentadiene epoxy resin, and / or alicyclic epoxy resin.

[0048] While not limited thereto, the amount of supported zinc dimolybdate hydroxide / silicon dioxide chalcogenide in the polymer composition is typically in the range of 1 to 50 phr (per 100 parts by weight of resin). Therefore, illustrative and non-limiting amounts of supported zinc dimolybdate hydroxide / silicon dioxide chalcogenide in the polymer composition may include the following ranges: 5 to 50 phr, 2 to 40 phr, 5 to 40 phr, 10 to 50 phr, 10 to 40 phr, 10 to 30 phr, or 15 to 40 phr. Other suitable ranges for the amount of supported zinc dimolybdate hydroxide / silicon dioxide chalcogenide in the polymer composition will readily become apparent from the present invention.

[0049] Where appropriate, the polymer composition may further contain any suitable additives, non-limiting examples of which may include stabilizers, lubricants, inorganic flame retardants (e.g., aluminum trihydrate or magnesium hydroxide), fillers, colorants, curing agents, catalysts or accelerators or fibers (e.g., glass fibers, carbon fibers, paper fibers, nonwoven fibers) and the like, and combinations thereof.

[0050] The articles may be formed from and / or may contain any of the polymer compositions described herein. In one embodiment, the articles may contain wires or cables, while in another embodiment, the articles may contain printed circuit boards. Other suitable articles and end-use applications will readily become apparent from the present invention.

[0051] For example, spherical zinc dimolybdate hydroxide / silicon dioxide complexes can be used in at least three applications, including industrial composite prepregs and microelectronics manufacturing, to provide benefits such as enhanced finished product properties and improved manufacturing processes. The first application is in printed circuit boards (PCBs), the second in epoxy molding compounds (EMCs) such as in microchip packaging, and the third is in industrial composite prepregs where flame retardancy and drilling are required, such as in aerospace and automotive end-uses.

[0052] Printed circuit boards (PCBs) are ubiquitous in electronic components of consumer and industrial products, including televisions, cell phones, and computers. Manufacturers typically use flame-retardant chemicals to produce PCBs to help ensure fire safety. Flame retardants can completely prevent the development of a fire or slow its accumulation phase by delaying the occurrence of a flash, thereby extending the escape window. In either case, the primary purpose of flame retardants is to reduce the risk of fire-related deaths. However, some flame-retardant chemicals, if released into the environment, raise increasing questions about their fate and toxicity. This is the case with tetrabromobisphenol A (TBBPA), or TBBPA. TBBPA is the most widely used flame retardant for PCBs. In this article, the single component offers several benefits, including halogen-free flame retardancy, improved drilling, thermal expansion control, and dimensional stability.

[0053] A basic PCB consists of a flat sheet of insulating material and layers of copper foil laminated to a substrate. Chemical etching divides the copper into individual conductors called tracks or circuit traces, pads for connections, through-holes for connections between copper layers, and features for electromagnetic shielding or other purposes, such as solid conductive areas. Printed circuit boards may have multiple copper layers. Double-layer boards have copper on both sides; multilayer boards sandwich additional copper layers between insulating material layers. Conductors on different layers are connected to through-holes, which are copper-plated holes that act as electrical channels through the insulating substrate. Through-hole component leads sometimes also effectively function as through-holes. "Through-hole" components are mounted by having their wire leads pass through the board and soldered to traces on the other side. Through-hole manufacturing increases board costs by requiring the precise drilling of many holes. Holes through PCBs with a diameter greater than 76.2 micrometers are typically drilled using drill bits made of solid-coated tungsten carbide. Advantageously, the disclosed composition has high thermal stability and is suitable for lead-free soldering.

[0054] Key properties include the flame retardancy of the laminate, dielectric constant (er), loss factor (tδ), tensile strength, shear strength, glass transition temperature (Tg), and Z-axis coefficient of thermal expansion (how the thickness changes with temperature). Thermal expansion is a significant consideration, especially in the case of ball grid arrays (BGAs) and bare grain technology, and glass fibers typically provide the best dimensional stability. As the size and frequency of plate features decrease, smaller inhomogeneities such as the non-uniform distribution of glass fibers or other fillers, thickness variations and bubbles in the resin matrix, and related local variations in the dielectric constant become increasingly important. The small particle size of the supported complexes disclosed is consistent with these issues.

[0055] The complexes described herein can be used as fillers in epoxy molding compounds (EMCs). Epoxy molding compounds are widely used for sealing semiconductor devices due to their excellent properties such as high mechanical strength and high productivity. Typically, in this case, a liquid epoxy polymer is injected over the circuit and cured into a solid for protection. In this paper, the supported complexes impart extremely low coefficient of thermal expansion (CTE), good dimensional stability, and flame retardancy to the semiconductor device package without significantly increasing viscosity during the manufacturing process.

[0056] Referring to industrial composite prepreg applications, prepreg represents "pre-impregnated" composite fibers. More specifically, a prepreg is a composite material in which reinforcing fibers are pre-impregnated with a thermoplastic or thermosetting resin matrix. It is a form of composite material that requires additional conversion or manufacturing into a fully cured final part. Epoxy resin is the most common thermosetting polymer matrix material. The fibers are usually woven and bonded together and to other components using the matrix during manufacturing. Thermosetting matrices are only partially cured to allow for easy handling. This partially cured epoxy material is also known as B-stage material. Composite prepregs are increasingly used in high-performance applications across a variety of industrial sectors. Some examples of prepreg applications include aircraft interiors, aerospace components, aircraft floors, cargo liners, automotive parts and components, tooling, bulletproof plates, electronic transmission applications, sporting goods, high-rise floors, high-impact floor surfaces, rotor blades and correctors in wind turbines, and orthopedic techniques in prostheses. The supported complexes described herein, when added as fillers, provide the desired flame retardancy, extremely low coefficient of thermal expansion (CTE), and good dimensional stability. In applications requiring composite drilling, the supported zinc dimolybdate hydroxide / silicon dioxide complexes also improve drillability by reducing borehole defects, extending drill bit life, and minimizing downtime.

[0057] Supported complexes can also be used in thermal interface materials due to their high thermal conductivity and low viscosity resulting from particle sphericity. Supported complexes (or silica, or both) can also be surface-treated with silanes and / or other surfactants, such as epoxy silanes, aniline silanes, methpropylene silanes, isocyanate silanes, and the like. Improved compound properties can be achieved after surface treatment. Benefits include lower resin compound viscosity, better compatibility with polymer resins, and less agglomeration.

[0058] Where necessary, sealing packaging techniques can be applied to supported complexes, such as a combination of larger and smaller silica particles (e.g., bimodal particle size distribution) rather than a single particle size distribution. This can improve the viscosity of the compound at extremely high loadings (up to 80 wt.% or greater). Examples

[0059] The present invention is further illustrated by the following embodiments, which should not be construed as limiting the scope of the invention in any way. After reading the description herein, those skilled in the art will conceive of various other forms, modifications, and equivalents without departing from the spirit of the invention or the scope of the appended claims.

[0060] d50 particle size or median particle size refers to the particle size at which 50% of the sample by weight has a smaller size and 50% of the sample has a larger size. Particle size measurements (including d10, d50, d90 and d100) are determined by laser diffraction according to ISO 13320 using a Beckman Coulter LS 13 320 single-wavelength laser diffraction particle size analyzer.

[0061] The BET surface area was determined using a Micromeritics TriStar II surface area and porosity analyzer, according to the BET nitrogen adsorption method described by Brunauer et al., J. Am. Chem. Soc., 60, 309 (1938). Examples 1 to 11 and Comparative Example A

[0062] In Example 1, 161.8 g (1988 mmol) of zinc oxide (d50 of 0.31 μm, Zochem Inc.) and 1.25 L of deionized water were placed in a reactor vessel equipped with a stirrer and a temperature controller, and heated with stirring at 85°C. Separately, 191.2 g (1328.4 mmol) of molybdenum trioxide (Langeloth Metallurgical Company) and 382.5 g of deionized water were added to a beaker at 85°C to form a slurry. Once the two were thoroughly mixed, the molybdenum trioxide slurry was pumped into the reactor vessel containing the zinc oxide solution at a peristaltic pump at 30 mL / min. The reaction mixture was then stirred at 85°C for 1 hour, followed by the addition of 1412 g of spherical molten silica (nominal d50 of 0.6 μm, d10 of 0.3 μm, d100 of 3 μm, and BET surface area of ​​6.2 m² / g; Denka Company Limited; Figure 1 illustrates the sphericity of the molten silica), and stirring continued for another 6 hours. The product mixture was then poured into a glass dish and dried overnight in an oven at 120°C. The dried product was depolymerized in a Henschel at 1800 rpm for 3 minutes, and then hammer-milled to reduce to the specified particle size distribution.

[0063] In Example 2A, 323.6 g (3976 mmol) of zinc oxide (d50 of 0.31 μm) and 2.5 L of deionized water were placed in a reactor vessel and heated with stirring at 85°C. Separately, 382.4 g (2656.7 mmol) of molybdenum trioxide and 765 g of deionized water were added to a beaker at 85°C to form a slurry. Once the two were thoroughly mixed, the molybdenum trioxide slurry was pumped into the reactor vessel containing the zinc oxide solution at a peristaltic pump at 30 mL / min. The reaction mixture was then stirred at 85°C for 1 hour, followed by the addition of 2824 g of spherical molten silicon dioxide (nominal d50 of 0.4 μm, d10 of 0.2 μm, d100 of 0.8 μm, and BET surface area of ​​11.3 m² / g; Denka Company Limited), and then stirred for another 6 hours. The product mixture was then poured into a glass dish and dried overnight in an oven at 120°C. The dried product was depolymerized in a Henschel at 1800 rpm for 3 minutes, and then hammer-milled to reduce the particle size distribution to the specified size distribution.

[0064] In Example 2B, 323.6 g (3976 mmol) of zinc oxide (d50 of 0.31 μm) and 2.5 L of deionized water were placed in a reactor vessel and heated with stirring at 85°C. Separately, 382.4 g (2656.7 mmol) of molybdenum trioxide and 765 g of deionized water were added to a beaker at 85°C to form a slurry. Once thoroughly mixed, the molybdenum trioxide slurry was pumped into the reactor vessel containing the zinc oxide solution at 30 mL / min using a peristaltic pump. The reaction mixture was then stirred at 85°C for 1 hour, followed by the addition of 1059 g of spherical molten silicon dioxide (d50 of 0.4 μm), and then stirred for another 6 hours. The product mixture was then poured into a glass dish and dried overnight in an oven at 120°C. The dried product was then depolymerized in a Henschel at 1800 rpm for 3 minutes, followed by hammer milling to reduce to the specified particle size distribution.

[0065] In Example 3, 50 g (614.3 mmol) of zinc oxide (d50 of 0.12 μm, Zochem Inc.) and 2.4 L of deionized water were placed in a reactor vessel and heated with stirring at 85°C. Separately, 62.5 g (434.2 mmol) of molybdenum trioxide and 125 g of deionized water were added to a beaker at 85°C to form a slurry. Once thoroughly mixed, the molybdenum trioxide slurry was pumped into the reactor vessel containing the zinc oxide solution at a peristaltic pump at 10 mL / min. The reaction mixture was then stirred at 85°C for 1 hour, followed by the addition of 535 g of spherical molten silicon dioxide (d50 of 4.12 μm, Imerys), and then stirred for another 2 hours. The product mixture was poured into a glass dish and dried overnight in an oven at 120°C. The dried product was depolymerized in a Henschel at 1800 rpm for 3 minutes, and then hammer-milled to reduce to the specified particle size distribution.

[0066] In Example 4, 25 g (307.2 mmol) of zinc oxide (d50 of 0.12 μm) and 2.4 L of deionized water were placed in a reactor vessel and heated with stirring at 85°C. Separately, 31.3 g (217.5 mmol) of molybdenum trioxide and 125 g of deionized water were added to a beaker at 85°C to form a slurry. Once thoroughly mixed, the molybdenum trioxide slurry was pumped into the reactor vessel containing the zinc oxide solution at 10 mL / min using a peristaltic pump. The reaction mixture was then stirred at 85°C for 1 hour, followed by the addition of 535 g of spherical molten silicon dioxide (d50 of 4.12 μm), and then stirred for another 2 hours. The product mixture was poured into a glass dish and dried overnight in an oven at 120°C. The dried product was depolymerized in a Henschel at 1800 rpm for 3 minutes, and then hammer-milled to reduce to the specified particle size distribution.

[0067] In Example 5, 28 g (344 mmol) of zinc oxide (d50 of 0.12 μm) and 2.4 L of deionized water were placed in a reactor vessel and heated with stirring at 85°C. Separately, 31.3 g (217.5 mmol) of molybdenum trioxide and 125 g of deionized water were added to a beaker at 85°C to form a slurry. Once thoroughly mixed, the molybdenum trioxide slurry was pumped into the reactor vessel containing the zinc oxide solution at 10 mL / min using a peristaltic pump. The reaction mixture was then stirred at 85°C for 1 hour, followed by the addition of 535 g of spherical molten silicon dioxide (d50 of 0.6 μm), and then stirred for another 2 hours. The product mixture was poured into a glass dish and dried overnight in an oven at 120°C. The dried product was depolymerized in a Henschel at 1800 rpm for 3 minutes, and then hammer-milled to reduce to the specified particle size distribution.

[0068] In Example 6, 28 g (344 mmol) of zinc oxide (d50 of 0.12 μm) and 2.4 L of deionized water were placed in a reactor vessel and heated with stirring at 85°C. Separately, 31.3 g (217.5 mmol) of molybdenum trioxide and 125 g of deionized water were added to a beaker at 85°C to form a slurry. Once thoroughly mixed, the molybdenum trioxide slurry was pumped into the reactor vessel containing the zinc oxide solution at 10 mL / min using a peristaltic pump. The reaction mixture was then stirred at 85°C for 1 hour, followed by the addition of 535 g of spherical molten silicon dioxide (d50 of 0.6 μm), and then stirred for another 6 hours. The product mixture was poured into a glass dish and dried overnight in an oven at 120°C. The dried product was depolymerized in a Henschel at 1800 rpm for 3 minutes, and then hammer-milled to reduce to the specified particle size distribution.

[0069] In Example 7, 28 g (344 mmol) of zinc oxide (d50 of 0.12 μm) and 2.4 L of deionized water were placed in a reactor vessel and heated with stirring at 85°C. Separately, 31.3 g (217.5 mmol) of molybdenum trioxide and 125 g of deionized water were added to a beaker at 85°C to form a slurry. Once the two were thoroughly mixed, the molybdenum trioxide slurry was pumped into the reactor vessel containing the zinc oxide solution at 10 mL / min using a peristaltic pump. The reaction mixture was then stirred at 85°C for 1 hour, followed by the addition of 1070 g of spherical molten silicon dioxide (d50 of 0.6 μm), and then stirred for another 6 hours. The product mixture was poured into a glass dish and dried overnight in an oven at 120°C. The dried product was depolymerized in a Henschel at 1800 rpm for 3 minutes, and then hammer-milled to reduce to the specified particle size distribution.

[0070] In Example 8, 50 g (614.3 mmol) of zinc oxide (d50 of 0.12 μm) and 2.4 L of deionized water were placed in a reactor vessel and heated with stirring at 50°C. Separately, 62.5 g (434.2 mmol) of molybdenum trioxide and 125 g of deionized water were added to a beaker at 50°C to form a slurry. Once thoroughly mixed, the molybdenum trioxide slurry was pumped into the reactor vessel containing the zinc oxide solution at 10 mL / min using a peristaltic pump. The reaction mixture was then stirred at 50°C for 1 hour, followed by the addition of 535 g of spherical silicon dioxide (d50 of 0.6 μm), and then stirred for another 6 hours. The product mixture was poured into a glass dish and dried overnight in an oven at 120°C. The dried product was depolymerized in a Henschel at 1800 rpm for 3 minutes, and then hammer-milled to reduce to the specified particle size distribution.

[0071] In Example 9, 50 g (614.3 mmol) of zinc oxide (d50 of 0.12 μm) and 2.4 L of deionized water were placed in a reactor vessel and stirred at room temperature. Separately, 62.5 g (434.2 mmol) of molybdenum trioxide and 125 g of deionized water were added to a beaker at room temperature to form a slurry. Once the two were thoroughly mixed, the molybdenum trioxide slurry was pumped into the reactor vessel containing the zinc oxide solution at 10 mL / min using a peristaltic pump. The reaction mixture was then stirred at room temperature for 1 hour, followed by the addition of 1070 g of spherical silicon dioxide (d50 of 0.6 μm), and then stirred for another 6 hours. The product mixture was poured into a glass dish and dried overnight in an oven at 120°C. The dried product was depolymerized in a Henschel at 1800 rpm for 3 minutes, and then hammer-milled to reduce to the specified particle size distribution.

[0072] In Example 10, zinc dimolybdate hydroxide was produced in a manner similar to that of Example 1, but the reaction mixture slurry was rapidly dried (without adding silicon dioxide) and then depolymerized using a Mikro ACM air-sorting mill at a d50 of 3.3 μm to form zinc dimolybdate hydroxide. Next, 100 g of zinc dimolybdate hydroxide, 400 g of spherical molten silicon dioxide (d50 of 0.6 μm), and 700 g of deionized water were placed in the grinding chamber of a ball mill without grinding media. The slurry mixture was then stirred at 600 rpm for 6 hours at approximately 22°C. The product mixture was poured into a glass dish and dried overnight in an oven at 110°C. The dried product was depolymerized in a Henschel at 1800 rpm for 3 minutes, and then hammer-milled to reduce to the specified particle size distribution.

[0073] In Example 11, 20 g of zinc dimolybdate hydroxide (produced in a manner similar to that in Example 10, with a d50 of 3.3 μm) and 80 g of spherical molten silicon dioxide (d50 of 0.6 μm) were placed in a polypropylene bottle and placed in a modified blue M oven and rotated overnight at approximately 22°C.

[0074] The spherical zinc dimolybdate hydroxide / silicon dioxide complexes produced in Examples 1 to 11 typically have a d10 particle size in the range of 0.3 to 0.5 μm, a d50 particle size in the range of 0.6 to 1.5 μm, a d100 particle size in the range of 4 to 5 μm, a particle size span in the range of 2.5 to 3 μm, and a BET surface area in the range of 5.5 to 9 m² / g. Except for Example 2B, these complexes also have a zinc content of about 7 wt.% and a molybdenum content of about 7 wt.%, while Example 2B has an independent zinc and molybdenum content of about 14 wt.%.

[0075] Comparative Example A was prepared using the same silicon dioxide as in Example 1, but following the steps described in U.S. Patent No. 6,190,787, wherein molybdenum trioxide and silicon dioxide were first combined, followed by the addition of zinc oxide. The complex obtained in Comparative Example A was compared with that of Example 1 (and other representative examples) using XRD analysis to determine differences in crystal structure. Powder samples were loaded into a Panalytical X'pert MPD diffractometer using Cu radiation at 45 kV / 40 mA. Scans were run from 6° to 80° with a step size of 0.0131° and a counting time of 250 seconds per step. Once the diffraction pattern was obtained, the phase was identified using powder diffraction documents published by the International Diffraction Data Center or the Inorganic Crystal Structure Database. XRD data indicated that approximately 25 wt.% of the amorphous phase was attributed to silicon dioxide; subtracting this resulted in the decomposition of the crystalline phase shown in Table I. Surprisingly, Example 1 contained all (about 99 wt.%) zinc dimolybdate hydroxide - Zn3Mo2O8(OH)2, while Comparative Example A contained only about 60 wt.% Zn3Mo2O8(OH)2 plus about 15 wt.% hydrate - ZnMoO4·0.8 H2O - and 25 wt.% unknown crystalline phase.

[0076] Compounds containing zinc and molybdenum may have difficulty adhering sufficiently to a silicon dioxide substrate. To demonstrate the improvements disclosed herein, Figure 2 is a scanning electron micrograph (SEM) of the supported zinc dimolybdate hydroxide / silicon dioxide complex of Example 1, and Figure 3 is an SEM of the complex of Comparative Example A. Advantageously, Figure 2 shows greater adhesion of zinc dimolybdate hydroxide to silicon dioxide compared to Figure 3, which shows more unsupported zinc molybdate particles not adhering to the silicon dioxide substrate. Examples 12 to 15

[0077] In Examples 13 to 15, a two-step melt blending process was used to incorporate zinc dimolybdate hydroxide / silicon dioxide complex into plasticized polyvinyl chloride. In the first step, PVC, plasticizer, stabilizer, lubricant, antimony dioxide, ATH, and MgOH2 were mixed at 90°C using a Henschel mixer to form a PVC premix, the composition of which is shown in Table II. In the second step, 24.64 g of the zinc dimolybdate hydroxide / silicon dioxide complex was added to 350.36 g of the PVC premix, and then mixed for 5 min at 165°C and 45 rpm using a Brabender Intelli-Torque Plasti-Corder mixer equipped with roller blades. Analytical samples were prepared by pressing the material using a Givin PHI hydraulic press at 78.3 bar pressure and 196°C. Example 12 used only the PVC premix, while Examples 13 to 15 used the zinc dimolybdate hydroxide / silicon dioxide complexes of Examples 9 to 11, respectively. Table III summarizes the values ​​of Examples 12 to 15 in phr.

[0078] Flame resistance tests were performed on samples using a cone calorimeter (DEATAK CC-2) following the procedures described in ASTM E 1354. 100 mm × 100 mm × 0.635 mm samples were measured in a horizontally exposed position. An external heat flux of 50 kW / m² was used for the tests. Measured parameters included duration of ignition, peak rate release rate (PHRR), average rate of heat release (RHR) over 60 seconds, total heat released (THR), average effective heat of combustion, initial mass, final mass, sample mass loss, average rate of mass loss (10% to 90%), average SEA, maximum average rate of heat evolved (MARHE), total smoke production, and average normalized total smoke production. The reported data are averages from three tests.

[0079] Figure 4 illustrates the heat release rate (HRR) curves of the four flame retardant polymer compositions of Examples 12 to 15, and Table IV summarizes the flame retardant properties (from Figure 4). Advantageously and unexpectedly, the flame retardant compositions of Examples 13 to 15 (containing zinc dimolybdate hydroxide / silicon dioxide complex) each have lower peak heat release rate (PHRR; Example 13 has the lowest PHRR), total heat release (THR; Example 15 has the lowest THR), and maximum average heat release rate (MARHE; Example 14 has the lowest MARHE) values ​​than Example 12. In addition, the total smoke production and average normalized total smoke production of Examples 13 to 15 are significantly lower than those of Example 12. Examples 16 to 19

[0080] In Examples 16 to 19, silicon dioxide or zinc dimolybdate hydroxide / silicon dioxide complexes were incorporated into the epoxy resin, wherein the compositions are shown in Table V (values ​​are in phr). Examples 17 to 19 utilized the zinc dimolybdate hydroxide / silicon dioxide complexes of Examples 1, 2B, and 2A, respectively. Example 16 utilized only silicon dioxide. For each example, during the removal of a 2 mm thick sheet layer, the wear and abrasiveness of 10 sheets measuring 100 × 100 × 7 mm on abrasive / drill bits were tested.

[0081] Figure 5 illustrates the drill bit before (top) and after (bottom) drilling the epoxy sheets of Example 16 (label 1) and Example 17 (label 2), while Figure 6 illustrates the drill bit before (top) and after (bottom) drilling the epoxy sheets of Example 18 (label 3) and Example 19 (label 4). Unexpectedly, and advantageously, the bottom (after grinding) image shows that the epoxy sheets (Examples 17 to 19) loaded with 5 phr spherical silicon dioxide and 25 phr supported zinc dimolybdate hydroxide / silicon dioxide complex perform much better in terms of drilling machinability than the epoxy sheet (Example 16) loaded with 30 phr spherical silicon dioxide – less wear and lower abrasiveness. From strongest to weakest abrasiveness, Example 16 (label 1), followed by Example 17 (label 2) and Example 19 (label 4), followed by Example 18 (label 3). Abrasiveness is related to zinc / molybdenum content: Example 16 contains no zinc / molybdenum and has the strongest abrasiveness, while Example 18 contains the most zinc / molybdenum and has the weakest abrasiveness. Examples 17 and 19 contain the same amount of zinc / molybdenum but have different silica particle sizes; therefore, this particle size has almost no effect on abrasiveness compared to the amount of zinc / molybdenum in epoxy formation. Table I: Crystalline phase analysis (wt.%). Example 1 Comparative Example A Zn3Mo2O8(OH)2 ~ 99 ~ 60 ZnMoO4·0.8 H2O ~ 1 ~ 14.7 Unknown phase -- ~ 25.3 Table II: Composition of PVC premix. Ingredients describe PHR Wt. % gram PVC resin GA Gulf 5415 (K70) 100 46.88 1406.47 plasticizers TOTM 48 22.50 675.11 stabilizer Ca / Zn Chemson 3 1.41 42.19 lubricant acid 0.3 0.14 4.22 Sb203 antimony 2 0.94 28.13 ATH H710 43 20.16 604.78 Mag V90SF 17 7.97 239.10 total 213.3 100 3000 Table III: Examples 12 to 15. Example 12 13 14 15 premix 360 336.35 336.35 336.35 Example 9 23.65 Example 10 23.65 Example 11 23.65 total 360 360 360 360 Table IV: Overview of ASTM E1354 test results. test unit Example 12 PVC premix Example 13 uses Example 9 Example 14 uses Example 10 Example 15 uses Example 11 Continuous ignition time Second 10.99 9.64 9.57 9.83 Peak heat release rate (PHRR) kW / m 2 197.68 157.23 193.30 186.17 Average RHR within 60 seconds kW / m 2 130.18 97.10 104.65 86.20 Average RHR over 180 seconds kW / m 2 29.33 0.00 0.00 0.00 Average RHR over 300 seconds kW / m 2 0.00 0.00 0.00 0.00 Total heat release (THR) MJ / m 2 11.17 8.20 10.00 7.87 Average effective heat of combustion MJ / kg 14.22 12.61 13.80 11.63 initial mass g 9.77 9.57 10.60 9.57 Final quality g 1.88 2.98 3.34 2.77 Sample mass loss kg / m 2 0.79 0.66 0.73 0.68 Average mass loss rate (10% to 90%) g / m 2 s 7.70 8.77 7.90 7.50 Average SEA m 2 / kg 814.06 747.57 605.99 739.47 CO yield kg / kg 0.00 0.00 0.00 0.00 CO2 yield kg / kg 0.00 0.00 0.00 0.00 Total tobacco production m 2 / m 2 641.02 491.63 440.35 502.70 Maximum average heat release rate (MARHE) kW / m 2 249.19 196.69 182.66 182.91 Average normalized total tobacco production m 2 / m 2 / g 65.56 51.46 41.64 52.50 Table V: Epoxy Compounds. Ingredients 16 17 18 19 Epon 828 epoxy resin 100 100 100 100 Epikure 3300 hardener 24.4 24.4 24.4 24.4 Spherical molten silicon dioxide (nominal d50 of 0.6 μm) 30 5 5 5 Example 1 25 Example 2B 25 Example 2A 25

[0082] The present invention has been described above with reference to numerous embodiments and specific examples. Those skilled in the art will recognize many variations from the above embodiments. All such apparent variations are within the full scope of the appended claims. Other embodiments of the invention may include, but are not limited to, the following (the embodiments are described as "comprising" the following, but alternatively, may "consist substantially of" or "comprise" the following):

[0083] Sample 1. A process for producing a supported zinc dimolybdate hydroxide / silicon dioxide complex, the process comprising: (i) reacting a zinc compound (e.g., zinc oxide, zinc chloride, zinc nitrate) with molybdenum trioxide (MoO3) in an aqueous system to form a reaction mixture; and (ii) contacting (or slurrying) the reaction mixture with silicon dioxide to form a supported zinc dimolybdate hydroxide / silicon dioxide complex.

[0084] Form 2. The process as defined in Form 1, wherein steps (i) and (ii) are performed independently at any suitable range or any range disclosed herein, such as 20°C to 95°C, 50°C to 95°C, 75°C to 90°C or 80°C to 90°C.

[0085] State 3. The process as defined in State 1 or 2, wherein the zinc compound and molybdenum trioxide react in any suitable range or any range of Zn:Mo ratios disclosed herein, such as 1:1 to 2:1, 1.2:1 to 1.8:1, 1.3:1 to 1.7:1 or 1.4:1 to 1.6:1, based on the total amount of each reactant.

[0086] Form 4. The process as defined in any of the preceding forms, wherein steps (i) and (ii) are performed independently at atmospheric or sub-atmospheric pressure within any suitable range or any range disclosed herein, for example, from 5 psig to 100 psig.

[0087] Sample 5. A process for producing a supported zinc dimolybdate hydroxide / silicon dioxide complex, the process comprising contacting (or slurrying) zinc dimolybdate hydroxide with silicon dioxide in an aqueous system to form a supported zinc dimolybdate hydroxide / silicon dioxide complex.

[0088] Form 6. The process as defined in Form 5, wherein the supported zinc dimolybdate hydroxide / silicon dioxide complex is formed at a temperature within any suitable range or any range disclosed herein, such as 15°C to 95°C, 15°C to 50°C or 20°C to 35°C.

[0089] State 7. The process as defined in State 5 or 6, wherein the supported zinc dimolybdate hydroxide / silicon dioxide complex is formed at atmospheric pressure or sub-atmospheric pressure within any suitable range or any range disclosed herein, for example, from 5 psig to 100 psig.

[0090] Form 8. The process of any of the foregoing forms further includes the step of removing the supported zinc dimolybdate hydroxide / silicon dioxide complex from water using any suitable technology or any technology disclosed herein, such as filtration or centrifugation and combinations thereof.

[0091] Form 9. The process as defined in any of the preceding forms further includes the step of drying the supported zinc dimolybdate hydroxide / silicon dioxide compound under any suitable drying conditions or any drying conditions disclosed herein, such as at a drying temperature in the range of 50°C to 200°C or 100°C to 150°C, and drying at atmospheric or sub-atmospheric pressure, such as less than 150 Torr or less than 50 Torr.

[0092] Form 10. The process as defined in any of the preceding forms, further comprising a step of depolymerizing the supported zinc dimolybdate hydroxide / silicon dioxide complex, a step of grinding the supported zinc dimolybdate hydroxide / silicon dioxide complex, or both.

[0093] State 11. A supported zinc dimolybdate hydroxide / silicon dioxide complex, which is produced by a process as defined in any one of States 1 to 10.

[0094] State 12. A supported zinc dimolybdate hydroxide / silicon dioxide complex comprising: (a) silicon dioxide; and (b) zinc dimolybdate hydroxide in an amount ranging from 3 to 20 wt.% zinc based on the total weight of the supported zinc dimolybdate hydroxide / silicon dioxide complex; wherein at least 80 wt.% of the zinc dimolybdate hydroxide is present in the crystalline form Zn3Mo2O8(OH)2.

[0095] State 13. A process or compound as defined in any of the preceding states, wherein the silicon dioxide is characterized by any suitable median particle size (d50) or any range disclosed herein, such as 0.2 to 5 µm, 0.2 to 25 µm, 0.2 to 1 µm or 0.25 to 0.8 µm.

[0096] Sample 14. A process or compound as defined in any of the preceding samples, wherein the silicon dioxide is characterized by any suitable d100 particle size or any range disclosed herein, such as 0.6 to 10 µm, 0.6 to 5 µm, 0.6 to 4 µm, 0.7 to 4 µm or 0.7 to 3.5 µm.

[0097] State 15. A process or compound as defined in any of the preceding states, wherein the silicon dioxide is characterized by any suitable d10 particle size or within any range disclosed herein, such as 0.08 to 1 µm, 0.08 to 0.5 µm, 0.1 to 0.5 µm or 0.1 to 0.4 µm.

[0098] State 16. A process or compound as defined in any of the preceding states, wherein the silicon dioxide is characterized by any suitable BET surface area or within any range disclosed herein, such as 2 to 20 m² / g, 4 to 15 m² / g, 4 to 12 m² / g, 5 to 15 m² / g or 5 to 13 m² / g.

[0099] State 17. A process or compound as defined in any of the aforementioned states, wherein the silicon dioxide is molten silicon dioxide, or spherical silicon dioxide, or spherical molten silicon dioxide.

[0100] State 18. The supported zinc dimolybdate hydroxide / silicon dioxide complex as defined in any of States 11 to 17, wherein the supported zinc dimolybdate hydroxide / silicon dioxide complex contains any suitable amount of zinc or in any range disclosed herein, such as 3 to 20 wt.%, 3 to 18 wt.%, 4 to 16 wt.%, or 5 to 15 wt.%.

[0101] State 19. A supported zinc dimolybdate hydroxide / silicon dioxide complex as defined in any of States 11 to 18, wherein the supported zinc dimolybdate hydroxide / silicon dioxide complex contains any suitable amount of molybdenum or any amount of molybdenum within any range disclosed herein, such as 3 to 20 wt.%, 3 to 18 wt.%, from 4 to 16 wt.% or 5 to 15 wt.%.

[0102] State 20. A supported zinc dimolybdate hydroxide / silicon dioxide complex as defined in any of States 11 to 19, wherein any suitable amount or within any range disclosed herein, such as at least 80 wt.%, at least 85 wt.%, at least 90 wt.%, or at least 95 wt.%, of zinc dimolybdate hydroxide is present as Zn3Mo2O8(OH)2.

[0103] State 21. A supported zinc dimolybdate hydroxide / silicon dioxide wrought compound as defined in any of States 11 to 20, wherein the supported zinc dimolybdate hydroxide / silicon dioxide wrought compound is characterized by any suitable median particle size (d50) or any range disclosed herein, such as 0.3 to 6 µm, 0.3 to 2 µm, 0.4 to 1.8 µm or 0.5 to 1.7 µm.

[0104] State 22. A supported zinc dimolybdate hydroxide / silicon dioxide wrought compound as defined in any of States 11 to 21, wherein the supported zinc dimolybdate hydroxide / silicon dioxide wrought compound is characterized by any suitable d100 particle size or any range disclosed herein, such as 1 to 12 µm, 1 to 8 µm, 1.5 to 7 µm, 2 to 7 µm or 2.5 to 6 µm.

[0105] State 23. A supported zinc dimolybdate hydroxide / silicon dioxide wrought compound as defined in any of States 11 to 22, wherein the supported zinc dimolybdate hydroxide / silicon dioxide wrought compound is characterized by any suitable d10 particle size or any range disclosed herein, such as 0.1 to 1.5 µm, 0.1 to 0.8 µm, 0.1 to 0.7 µm or 0.2 to 0.6 µm.

[0106] State 24. A supported zinc dimolybdate hydroxide / silicon dioxide wrought compound as defined in any of States 11 to 23, wherein the supported zinc dimolybdate hydroxide / silicon dioxide wrought compound is characterized by any suitable span ((d90-d10) / d50) or any range disclosed herein, such as a span of 1.5 to 5, 1.5 to 4.5 or 2 to 4.

[0107] State 25. A supported zinc dimolybdate hydroxide / silicon dioxide complex as defined in any of States 11 to 24, wherein the supported zinc dimolybdate hydroxide / silicon dioxide complex is characterized by any suitable BET surface area or within any range disclosed herein, such as 3 to 20 m² / g, 3 to 15 m² / g, 3 to 12 m² / g, 4 to 13 m² / g or 4 to 10 m² / g.

[0108] State 26. A supported zinc dimolybdate hydroxide / silicon dioxide fusion compound as defined in any one of States 11 to 25, wherein the supported zinc dimolybdate hydroxide / silicon dioxide fusion compound is spherical.

[0109] State 27. A polymer composition (or formulation) comprising: (a) a polymer; and (b) a supported zinc dimolybdate hydroxide / silicon dioxide complex as defined in any one of States 11 to 26.

[0110] State 28. The polymer composition as defined in State 27, wherein the amount of the supported zinc dimolybdate hydroxide / silicon dioxide complex is any suitable amount or within any range disclosed herein, such as 1 to 50 phr, 5 to 50 phr, 2 to 40 phr, 5 to 40 phr, 10 to 50 phr, 10 to 40 phr, 10 to 30 phr or 15 to 40 phr.

[0111] State 29. A polymer composition as defined in State 27 or 28, wherein the polymer comprises any suitable polymer or any polymer disclosed herein, such as a thermoplastic polymer, a thermosetting polymer or a combination thereof.

[0112] State 30. A polymer composition as defined in State 27 or 28, wherein the polymer comprises polyvinylidene chloride (PVDC), polyvinyl chloride (PVC), chlorinated polyvinyl chloride (CPVC), polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), ethylene chloride trifluoroethylene (ECTFE), or any combination thereof.

[0113] State 31. A polymer composition as defined in State 27 or 28, wherein the polymer comprises rigid PVC.

[0114] State 32. A polymer composition as defined in State 27 or 28, wherein the polymer comprises flexible PVC.

[0115] State 33. A polymer composition as defined in State 27 or 28, wherein the polymer comprises plasticized or non-plasticized PVC.

[0116] State 34. A polymer composition as defined in State 27 or 28, wherein the polymer comprises an epoxy resin.

[0117] Form 35. A polymer composition as defined in Form 27 or 28, wherein the polymer comprises bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, phenolic epoxy resin, cresolic epoxy resin, bisphenol A phenolic epoxy resin, bisphenol F phenolic epoxy resin, stilbene epoxy resin, epoxy resin having a tri-framework, epoxy resin having a cyclopentadiene framework, triphenylmethane epoxy resin, biphenyl epoxy resin, xylene epoxy resin, biphenyl aralkyl epoxy resin, naphthalene epoxy resin, dicyclopentadiene epoxy resin, alicyclic epoxy resin, or any combination thereof.

[0118] Form 36. A polymer composition as defined in any one of Forms 27 to 35, wherein the polymer composition further comprises additives including stabilizers, lubricants, inorganic flame retardants (e.g., aluminum trihydrate or magnesium hydroxide), fillers, colorants, curing agents, catalysts or accelerators or fibers (e.g., glass fibers, carbon fibers, paper fibers, nonwoven fibers), and any combination thereof.

[0119] State 37. A process, complex or composition as defined in any of States 1 to 36, wherein the complex, or silicon dioxide, or both the complex and silicon dioxide include a surface treatment (e.g., silane surface treatment).

[0120] Specimen 38. An article comprising a polymer composition as defined in any one of Specimens 27 to 37.

[0121] State 39. Articles as defined in State 38, wherein the articles include wires or cables.

[0122] State 40. Articles as defined in State 38, wherein the articles include printed circuit boards. [Simplified Explanation of the Diagram]

[0009] [Figure 1] shows a scanning electron microscope image of the spherical molten silica component used in Example 1.

[0010] [Figure 2] shows a scanning electron microscope image of the supported zinc dimolybdate hydroxide / silicon dioxide complex of Example 1.

[0011] [Figure 3] shows a scanning electron microscope image of the supported zinc dimolybdate hydroxide / silicon dioxide complex of Comparative Example A.

[0012] [Figure 4] presents the heat release rate (HRR) curves of the flame retardant polymer compositions of Examples 12 to 15.

[0013] [Figure 5] Photographs of the drill bit before and after drilling the epoxy sheet in Examples 16 to 17.

[0014] [Figure 6] Photographs of the drill bit before and after drilling the epoxy sheet in Examples 18 to 19.

Claims

1. A process for producing a supported zinc dimolybdate hydroxide / silicon dioxide complex, the process comprising: (i) reacting a zinc compound with molybdenum trioxide (MoO3) in an aqueous system to form a reaction mixture, the aqueous system being substantially composed of water and an acid or base as desired for adjusting or controlling the pH of the system, the reaction mixture being substantially composed of a zinc compound, molybdenum trioxide, water and an acid or base as desired; (ii) contacting the reaction mixture with silicon dioxide to form the supported zinc dimolybdate hydroxide / silicon dioxide complex; and (iii) drying the supported zinc dimolybdate hydroxide / silicon dioxide complex.

2. As in the process described in request item 1, wherein: Steps (i) and (ii) are carried out independently at temperatures ranging from 20°C to 95°C; the zinc compound contains zinc oxide; and the zinc oxide reacts with the molybdenum trioxide in a molar ratio of Zn:Mo of 1:1 to 2:

1.

3. A process for producing a supported zinc dimolybdate hydroxide / silicon dioxide complex, the process comprising: (i) contacting zinc dimolybdate hydroxide with silicon dioxide in an aqueous system to form the supported zinc dimolybdate hydroxide / silicon dioxide complex, the aqueous system being substantially composed of: water and an acid or base as desired for adjusting or controlling the pH of the system; and (ii) drying the supported zinc dimolybdate hydroxide / silicon dioxide complex.

4. The process of claim 3, wherein the supported zinc dimolybdate hydroxide / silicon dioxide complex is formed at a temperature in the range of 15°C to 95°C.

5. The process of claim 1 further includes a step of removing the supported zinc dimolybdate hydroxide / silicon dioxide complex from water.

6. The process of claim 1, further comprising: depolymerizing the supported zinc dimolybdate hydroxide / silicon dioxide complex; milling the supported zinc dimolybdate hydroxide / silicon dioxide complex; or any combination thereof.

7. A supported zinc dimolybdate hydroxide / silicon dioxide complex, which is produced by the process described in claim 1.

8. A supported zinc dimolybdate hydroxide / silicon dioxide complex comprising: (a) silicon dioxide; and (b) zinc dimolybdate hydroxide fused with the silicon dioxide, wherein the zinc dimolybdate hydroxide is present in an amount ranging from 3 to 20 wt.% zinc based on the total weight of the supported zinc dimolybdate hydroxide / silicon dioxide complex; wherein at least 80 wt.% of the zinc dimolybdate hydroxide is present in the crystalline form Zn3Mo2O8(OH)2.

9. The complex of claim 8, wherein the silicon dioxide is characterized by: a d50 particle size of 0.2 to 5 µm; a d100 particle size of 0.6 to 10 µm; a d10 particle size of 0.08 to 1 µm; and a BET surface area of ​​2 to 20 m² / g.

10. The mismatched compound of claim 8, wherein: The silicon dioxide is molten silicon dioxide; the silicon dioxide is spherical silicon dioxide; or both.

11. As in claim 8, the mismatched compound, wherein: The supported zinc dimolybdate hydroxide / silicon dioxide complex contains 4 to 16 wt.% zinc; the supported zinc dimolybdate hydroxide / silicon dioxide complex contains 3 to 20 wt.% molybdenum; and at least 90 wt.% of the zinc dimolybdate hydroxide is present as Zn3Mo2O8(OH)2.

12. The complex of claim 8, wherein the supported zinc dimolybdate hydroxide / silicon dioxide complex is characterized by: a d50 particle size of 0.3 to 6 µm; a d100 particle size of 1 to 12 µm; a d10 particle size of 0.1 to 1.5 µm; a span of 1.5 to 5 ((d90-d10) / d50); and a BET surface area of ​​3 to 20 m² / g.

13. The complex of claim 8, wherein the supported zinc dimolybdate hydroxide / silicon dioxide complex is spherical.

14. A polymer composition comprising: (a) a polymer; and (b) the supported zinc dimolybdate hydroxide / silicon dioxide complex as claimed in claim 8.

15. The polymer composition of claim 14, wherein the polymer comprises a thermoplastic polymer.

16. The polymer composition of claim 14, wherein the polymer comprises a thermosetting polymer.

17. The polymer composition of claim 14, wherein the polymer comprises rigid PVC or flexible PVC.

18. The polymer composition of claim 14, wherein the polymer comprises an epoxy resin.

19. The polymer composition of claim 14, wherein: The amount of the supported zinc dimolybdate hydroxide / silicon dioxide complex is in the range of 1 to 50 phr; and the polymer composition further includes additives, which include stabilizers, lubricants, inorganic flame retardants, fillers, colorants, curing agents, catalysts or accelerators, fibers or any combination thereof.

20. An article comprising a polymer composition as claimed in claim 14.

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