Halogen-free flame-retardant thermoplastic polyester elastomer composition as well as preparation method and application thereof

Abstract

The invention provides a halogen-free flame-retardant thermoplastic polyester elastomer composition as well as a preparation method and application thereof. The halogen-free flame-retardant thermoplastic polyester elastomer composition comprises: 30-90 wt% of a thermoplastic polyester elastomer; 5 to 30 wt% of a derivative based on a 9, 10-dihydro-9-oxa-10-phosphaphenanthrene oxide as a skeleton structure; 1 to 10 weight percent of solid aromatic phosphate ester; 2 to 30 weight percent of melamine cyanurate; and 0.1-10 wt% of an auxiliary agent. Compared with the prior art, the halogen-free flame-retardant thermoplastic polyester elastomer composition provided by the invention adopts specific components with specific contents, realizes relatively good overall interaction, has excellent flame retardance and also has excellent processability and mechanical properties; a product prepared from the halogen-free flame-retardant thermoplastic polyester elastomer composition shows good flame retardance while having good mechanical characteristics, and also has good mechanical and chemical stability.

Description

Technical Field

[0001] The invention relates to the technical field of thermoplastic polyester elastomers, and more specifically to a halogen-free flame-retardant thermoplastic polyester elastomer composition, a preparation method and application thereof. Background Art

[0002] Since the composition composed of thermoplastic polyester elastomer has excellent mechanical properties (such as tear strength, tensile strength, flex life and wear resistance, etc.), it also has relatively light weight and good corrosion resistance, so it has a wide range of applications, such as motor vehicles and leisure vehicles, household appliances, tools, electronic devices, furniture and toys, and has even begun to replace metal materials in some application fields. However, in the fields of construction, furniture, transportation or electrical / electronics, due to the flammability of thermoplastic polyester elastomers, it also brings certain safety risks to people. Making the thermoplastic resin composition flame retardant to ensure product safety, prevent the spread of fire and reduce the destruction of products when exposed to fire has become an industry choice.

[0003] By adding one or more flame retardants or flame retardant mixtures to thermoplastic polyester elastomers, their flame retardancy can be systematically improved. The flame retardant solution composed of antimony trioxide combined with halogen flame retardants has improved the flame retardancy of thermoplastic polyester elastomers. However, halogenated flame retardants are prone to decompose or degrade to produce toxic gases during the processing and post-treatment of thermoplastic resins, leading to potential health and environmental impacts. Therefore, due to toxicity considerations, halogen-free flame retardant solutions are increasingly attracting industry attention.

[0004] Among the halogen-free flame retardant solutions, phosphorus-based flame retardants are most commonly used because of their high efficiency, environmental protection and small impact on the mechanical properties of materials. At present, various studies have shown that the use of phosphorus-based flame retardants blended with other halogen-free flame retardants can further improve the flame retardant efficiency and achieve synergistic effect to reduce the amount of addition. Patent CN1216094C discloses a polyester molding composition with flame retardant properties, which is mainly composed of polyester, red phosphorus flame retardant, and hydrotalcite and melamine cyanurate as flame retardant synergists; however, the fine red phosphorus powder with high flame retardancy is easy to catch fire and explode during processing. In addition, in the presence of water vapor, red phosphorus is prone to disproportionation to form oxygen-containing acid phosphorus and toxic gas phosphine, which also poses certain safety risks and greatly limits downstream applications. Compounds constructed with phosphorus-carbon bonds have good thermal stability and chemical stability, so dialkyl phosphinates, especially diethyl aluminum phosphinate, are increasingly used in the field of flame retardants. Patent CN101496115B discloses a mixture mainly composed of phosphinate and melamine derivatives for improving the flame retardancy of thermoplastic polyester elastomers, but the flame retardancy is unstable and cannot pass the strict UL94 V0 flame retardancy standard; in addition, dialkyl phosphinates are corrosive to a certain extent, which is particularly serious under high temperature conditions, and also reduce the mechanical properties of the material to a certain extent.

[0005] Cyclic phosphonates containing phosphorus-carbon bonds, especially derivatives based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide (DOPO) as the skeleton structure, have also been widely reported to have good thermal stability and flame retardancy. Japanese patent JPH11-106619 discloses a DOPO derivative DiDOPO, and applies it to flame retardant polyester fibers. Patent CN104086593B discloses the preparation of another DOPO derivative and its application in polycarbonate and epoxy resin, showing good flame retardancy. Patent CN104119673B discloses the application of this DOPO derivative in the field of high-temperature nylon, showing high efficiency flame retardancy and good fluidity.

[0006] The regulatory standards for flame retardant materials, especially in the cable industry, are increasingly being strengthened and improved. In order to further enhance the safety of personnel and the environment in fires, there is an urgent need to develop halogen-free flame retardant compositions with excellent flame retardancy and good mechanical properties. Summary of the invention

[0007] In view of this, the object of the present invention is to provide a halogen-free flame retardant thermoplastic polyester elastomer composition and a preparation method and application thereof. The products prepared by using the halogen-free flame retardant thermoplastic polyester elastomer composition have good mechanical properties and show good flame retardancy, and also have good mechanical and chemical stability.

[0008] The present invention provides a halogen-free flame-retardant thermoplastic polyester elastomer composition, comprising:

[0009] Thermoplastic polyester elastomer 30-90wt%;

[0010] 5 to 30 wt% of derivatives based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide as the framework structure;

[0011] Solid aromatic phosphate 1-10wt%;

[0012] Melamine cyanurate 2-30wt%;

[0013] Additives 0.1~10wt%.

[0014] Preferably, the derivative based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide as the skeleton structure has the following structure:

[0015]

[0016] Wherein, X is -H2C-CH2- or

[0017] Preferably, the solid aromatic phosphate has the following structure:

[0018]

[0019] Wherein, n is an integer of 1 to 4, m is an integer of 0 to 6; A is a divalent arylene moiety bonded to two oxygen atoms of any one of hydroquinone, resorcinol, 4,4'-biphenol, bisphenol S or bisphenol F; R1 is selected from one of C1 to C18 alkyl, C3 to C18 heteroaryl, and C6 to C18 aryl.

[0020] Preferably, the solid aromatic phosphate is hydroquinone bis(diphenyl phosphate) and / or resorcinol bis(di-2,6-dimethylphenyl phosphate).

[0021] Preferably, the D95 maximum value of the melamine cyanurate is 15 μm.

[0022] Preferably, the auxiliary agent is selected from one or more of antioxidants, processing aids, colorants, UV stabilizers, antistatic agents, nucleating agents, slip agents, plasticizers, lubricants, viscosity controllers, tackifiers, antiblocking agents, surfactants, extender oils, acid scavengers and metal deactivators.

[0023] Preferably, the halogen-free flame retardant thermoplastic polyester elastomer composition consists of the following components:

[0024] Thermoplastic polyester elastomer 38.5-58.5wt%;

[0025] 25-30wt% of derivatives based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide as the framework structure;

[0026] Solid aromatic phosphate 3-5wt%;

[0027] Melamine cyanurate 10-30wt%;

[0028] Additives 0.5~1wt%.

[0029] The present invention also provides a method for preparing the halogen-free flame-retardant thermoplastic polyester elastomer composition described in the above technical solution, comprising the following steps:

[0030] A thermoplastic polyester elastomer, a derivative based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide as a skeleton structure, a solid aromatic phosphate, melamine cyanurate and an additive are melt-blended, extruded into granules, and then dried and sealed to obtain a halogen-free flame-retardant thermoplastic polyester elastomer composition.

[0031] Preferably, the temperature of the melt blending is 150° C. to 190° C.; the temperature of the drying is 110° C. to 130° C., and the drying time is 5 h to 7 h.

[0032] The present invention also provides a product, comprising a component made from the halogen-free flame-retardant thermoplastic polyester elastomer composition described in the above technical solution.

[0033] The present invention provides a halogen-free flame-retardant thermoplastic polyester elastomer composition, a preparation method thereof and an application thereof; the halogen-free flame-retardant thermoplastic polyester elastomer composition comprises: 30-90wt% of thermoplastic polyester elastomer; 5-30wt% of derivatives based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide as a skeleton structure; 1-10wt% of solid aromatic phosphate; 2-30wt% of melamine cyanurate; and 0.1-10wt% of an auxiliary agent. Compared with the prior art, the halogen-free flame-retardant thermoplastic polyester elastomer composition provided by the present invention adopts specific components with specific contents to achieve overall good interaction, and has excellent flame retardancy as well as excellent processing performance and mechanical properties. The products prepared by using the halogen-free flame-retardant thermoplastic polyester elastomer composition have good mechanical properties, good flame retardancy, and good mechanical and chemical stability.

[0034] In addition, the preparation method provided by the present invention has simple process, mild conditions, easy control, and broad application prospects. DETAILED DESCRIPTION

[0035] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] The present invention provides a halogen-free flame-retardant thermoplastic polyester elastomer composition, comprising:

[0037] Thermoplastic polyester elastomer 30-90wt%;

[0038] 5 to 30 wt% of derivatives based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide as the framework structure;

[0039] Solid aromatic phosphate 1-10wt%;

[0040] Melamine cyanurate 2-30wt%;

[0041] Additives 0.1~10wt%.

[0042] The present invention provides a novel halogen-free flame-retardant thermoplastic polyester elastomer composition, the main components of which include: (a) 30-90wt% of at least one thermoplastic polyester elastomer; (b) 5-30wt% of a derivative based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide (DOPO) as a skeleton structure; (c) 1-10wt% of a solid aromatic phosphate; (d) 2-30wt% of a melamine cyanurate flame retardant; and (e) 0.1-10wt% of other necessary auxiliary agents. In the present invention, the total weight of the flame retardant mixture composed of (b), (c) and (d) is greater than or equal to 8wt%. A smaller amount of the flame retardant mixture cannot effectively achieve the flame retardancy of the thermoplastic polyester elastomer. At the same time, if the total weight of the above (a) is less than 30wt%, it is not conducive to the mechanical properties of the flame retardant polymer composition.

[0043] In the present invention, the halogen-free flame retardant thermoplastic polyester elastomer composition is preferably composed of the following components:

[0044] Thermoplastic polyester elastomer 38.5-58.5wt%;

[0045] 25-30wt% of derivatives based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide as the framework structure;

[0046] Solid aromatic phosphate 3-5wt%;

[0047] Melamine cyanurate 10-30wt%;

[0048] Additives 0.5-1wt%;

[0049] In the halogen-free flame-retardant thermoplastic polyester elastomer composition, the total weight of the thermoplastic polyester elastomer, the derivative based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide as the skeleton structure, the solid aromatic phosphate, the melamine cyanurate and the auxiliary components is 100 wt%.

[0050] In the present invention, the thermoplastic polyester elastomer is a raw material already available in the market and can be obtained commercially. The thermoplastic polyester elastomer generally comprises a block copolymer having a structure in which a polyester hard block (hard block or hard segment, such as aromatic polyester) is bonded to a polyester soft block (soft block or soft segment) through an ester bond. According to the type of the soft block, the thermoplastic polyester elastomer can be divided into two types, polyether-based and polyester-based. Any of these thermoplastic polyester elastomers can be used in the present invention.

[0051] In the present invention, the hard polyester constituting the hard block can be obtained by polycondensation of dicarboxylic acid and diol, polycondensation of hydroxycarboxylic acid and other methods; generally, an aromatic polyester obtained from at least an aromatic monomer component can be used. The aromatic monomer component may include, for example, aromatic diol and its reactive derivatives, aromatic dicarboxylic acid and terephthalic acid (and reactive derivatives of the aromatic dicarboxylic acid) and / or aromatic hydroxycarboxylic acid [for example, hydroxybenzoic acid, hydroxynaphthoic acid, 4-carboxy-4'-hydroxy-biphenyl, and derivatives of the hydroxycarboxylic acid (for example, alkyl, alkoxy or halogen substituted compounds)]. The aromatic monomer component may be used alone or in combination. In the aromatic polyester, copolymerizable monomers (including copolymerizable monomers, and in addition, 1,4-butanediol, terephthalic acid and others) may be used in combination if necessary. For the aromatic polyester, it is sufficient to use an aromatic monomer component as a monomer component; for example, the aromatic polyester may be a completely aromatic polyester (e.g., polyester of an aromatic dicarboxylic acid and an aromatic diol, and polyester of an aromatic hydroxycarboxylic acid), or may be a polyester of an aromatic dicarboxylic acid and a non-aromatic diol (e.g., 1,4-butanediol, and an aliphatic diol or an alicyclic diol), a polyester of a non-aromatic dicarboxylic acid (e.g., an aliphatic dicarboxylic acid) and an aromatic diol, and a polyester of an aromatic hydroxycarboxylic acid and a non-aromatic hydroxycarboxylic acid (e.g., an aliphatic hydroxycarboxylic acid such as glycolic acid or hydroxycaproic acid).

[0052] Among these hard polyesters, preferred hard polyesters include crystalline aromatic polyesters [e.g., polyalkylene arylates (e.g., poly C 2-4 Alkylene arylates such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate or polybutylene naphthalate, and modified poly (C 2-4Alkylene arylate (for example, poly (C) modified or copolymerized with 1 to 30 mol % (for example, about 3 to 25 mol % and preferably about 5 to 20 mol %) of a copolymerizable component (the above-mentioned copolymerizable monomer such as isophthalic acid) 2-4 Alkylene arylate))], and liquid crystal polyesters, particularly polybutylene terephthalate and the like; more preferred polybutylene terephthalate (PBT) resins may include homopolyesters or copolyesters containing butylene terephthalate units as main units (e.g., a ratio of about 50 to 100 wt%, preferably about 60 to 100 wt%, and more preferably about 70 to 100 wt%), for example, polybutylene terephthalate and polybutylene terephthalate copolyesters.

[0053] The copolymerizable monomer (or comonomer) in the copolyester (butylene terephthalate-series copolymer or modified PBT resin) may include dicarboxylic acids other than terephthalic acid, diols other than 1,4-butanediol, hydroxycarboxylic acids, lactones, and others. The copolymerizable monomers may be used alone or in combination.

[0054] In the present invention, the dicarboxylic acid may include, for example, aliphatic dicarboxylic acids (e.g., C 4-40 Aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, hexadecanedioic acid or dimer acid, preferably C 4-14 dicarboxylic acids), alicyclic dicarboxylic acids (such as C 8-12 Alicyclic dicarboxylic acids such as hexahydrophthalic acid, hexahydroisophthalic acid, hexahydroterephthalic acid or humic acid), aromatic dicarboxylic acids other than terephthalic acid (e.g., C 8-16 Aromatic dicarboxylic acids such as phthalic acid, isophthalic acid; naphthalene dicarboxylic acids such as 2,6-naphthalene dicarboxylic acid; and 4,4'-diphenyl dicarboxylic acid, 4,4'-diphenyloxy ether dicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, 4,4'-diphenyl methane dicarboxylic acid or 4,4'-diphenyl ketone dicarboxylic acid), or reactive derivatives thereof [e.g., derivatives capable of forming esters (or ester-forming derivatives), such as lower alkyl esters (e.g., C esters of phthalic acid or isophthalic acid)] 1-4 alkyl esters, such as dimethyl phthalate or dimethyl isophthalate (DMI); acid chlorides; acid anhydrides; and derivatives capable of forming esters (or ester-forming derivatives) such as alkyl-, alkoxy- or halogen-substituted dicarboxylic acid compounds].

[0055] In the present invention, the diol may include, for example, an aliphatic alkylene glycol other than 1,4-butanediol (e.g., a lower alkylene glycol such as ethylene glycol, trimethylene glycol, propylene glycol, neopentyl glycol, hexanediol (e.g., 1,6-hexanediol), octanediol (e.g., 1,3-octanediol), or decanediol (e.g., C 2-12 Alkylene glycol, preferably C 2-10 Alkylene glycol), polyoxyalkylene glycol [e.g., having multiple oxygen C 2-4 alkylene units, such as diethylene glycol, dipropylene glycol, ditetramethylene glycol, triethylene glycol, tripropylene glycol and polytetramethylene glycol], alicyclic diols (such as 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol and hydrogenated bisphenol A), aromatic diols [such as C 6-14 Aromatic diols such as hydroquinone, resorcinol or naphthalene diol; bisphenols (eg 4,4'-dihydroxybiphenyl); bisphenol compounds; and benzyl alcohol], and reactive derivatives thereof (eg derivatives capable of forming esters, such as alkyl-, alkoxy- or halogen-substituted diol compounds).

[0056] In the present invention, the bisphenol compound may include bis(hydroxyaryl)C 1-6 Alkyl groups, such as bis(4-hydroxyphenyl)methane (bisphenol F), 1,1-bis(4-hydroxyphenyl)ethane (bisphenol AD), 1,1-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxyphenyl)propane (bisphenol A), 2,2-bis(4-hydroxy-3-methylphenyl)propane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)-3-methylbutane, 2,2-bis(4-hydroxyphenyl)hexane or 2,2-bis(4-hydroxyphenyl)-4-methylpentane; bis(hydroxyaryl)C 4-10 Cycloalkanes, such as 1,1-bis(4-hydroxyphenyl)cyclopentane or 1,1-bis(4-hydroxyphenyl)cyclohexane; 4,4'-dihydroxydiphenyl ether; 4,4'-dihydroxydiphenyl sulfone; 4,4'-dihydroxydiphenyl sulfide; 4,4'-dihydroxydiphenyl ketone; and alkylene oxide adducts thereof; alkylene oxide adducts may include C of bisphenol compounds (e.g., bisphenol A, bisphenol AD, and bisphenol F); 2-3 Olefin oxide adducts, such as 2,2-bis-[4-(2-hydroxyethoxy)phenylpropane, diethoxylated bisphenol A (EBPA), 2,2-bis-[4-(2-hydroxypropoxy)phenyl]propane and dipropoxylated bisphenol A. In the alkylene oxide adducts, the number of moles of the added alkylene oxide (C 2-3 The olefin oxide such as ethylene oxide or propylene oxide) may be about 1 to 10 mol, and preferably about 1 to 5 mol, per hydroxyl group.

[0057] In the present invention, hydroxycarboxylic acids may include, for example, hydroxycarboxylic acids such as hydroxybenzoic acid, hydroxynaphthoic acid, hydroxyphenylacetic acid, 4-carboxy-4'-hydroxy-biphenyl, glycolic acid or hydroxycaproic acid, or derivatives thereof (e.g., alkyl-, alkoxy- or halogen-substituted compounds), and others. Lactones may include C 3-12 Lactones, such as propiolactone, butyrolactone, valerolactone or caprolactone (eg E-caprolactone) and others.

[0058] If necessary, these copolymerizable monomers can be used in combination with multifunctional compounds, such as polycarboxylic acids (such as trimesic acid, trimellitic acid or pyromellitic acid) or derivatives thereof capable of forming esters (such as alcohol esters), and polyols (such as glycerol, trimethylolpropane, trimethylolethane or pentaerythritol) or derivatives thereof capable of forming esters. The combined use of such multifunctional compounds will result in branched PBT series resins. Preferred copolymerizable monomers include diols [e.g., C 2-6 Alkylene glycol (e.g., a linear or branched alkylene glycol such as ethylene glycol, trimethylene glycol, propylene glycol or hexylene glycol), a polyoxyethylene glycol having about 2 to 4 repeating oxyalkylene units. 2-4 Alkylene glycol (e.g. diethylene glycol), and bisphenol compound (e.g. bisphenol compound or alkylene oxide adduct thereof)], dicarboxylic acid [e.g. C 6-12Aliphatic dicarboxylic acids (e.g., adipic acid, pimelic acid, suberic acid, azelaic acid and sebacic acid), asymmetric aromatic dicarboxylic acids having two carboxyl groups at asymmetric positions of their aromatic hydrocarbon rings, and 1,4-cyclohexanedimethanol], and others. Among these compounds, preferred compounds include aromatic compounds such as oxyalkylene adducts of bisphenol compounds (particularly bisphenol A), and asymmetric aromatic dicarboxylic acids [e.g., phthalic acid, isophthalic acid and reactive derivatives thereof (e.g., lower alkyl esters such as dimethyl isophthalate (DMI))] and others. Preferred is a PBT resin having a copolymerizable monomer unit having a ratio (amount) of not more than 30 mol% (0 to 30 mol%) of homopolyester (polybutylene terephthalate) and / or copolyester (copolymer). In the copolymer, the ratio of the copolymerizable monomer unit can be selected, for example, from the range of about 0.01 to 30 mol%. The ratio may generally be about 1 to 30 mol%, preferably about 3 to 25 mol%, and more preferably about 5 to 20 mol% (e.g., about 5 to 15 mol%). PBT series resins may be used alone or in combination. The present invention does not particularly limit the intrinsic viscosity (IV) of the PBT resin. For example, when measured in o-chlorophenol at 35°C, the intrinsic viscosity (IV) of the PBT resin may be about 0.6 to 1.4 dL / g; in view of hydrolysis resistance and extrusion processing performance, the above intrinsic viscosity may preferably be about 0.8 to 1.3 dL / g, and more preferably 0.85 to 1.2 dL / g; when the intrinsic viscosity is too low, the desired hydrolysis resistance or the desired extrusion processing performance (melt tension) may not be obtained sometimes; in addition, when the intrinsic viscosity is too high, the load applied during extrusion may increase. PBT resins can be produced by copolymerizing terephthalic acid or a reactive derivative thereof with 1,4-butanediol and, if necessary, copolymerizable monomers in a conventional manner such as ester exchange, direct esterification or other means.

[0059] In the present invention, the soft polyester constituting the soft block of the polyester-based elastomer can be obtained in the same manner as the PBT resin, by polycondensation of dicarboxylic acid and diol, polycondensation of hydroxycarboxylic acid or lactone, and others; it is sufficient as long as the soft polyester is softer than the hard polyester constituting the hard block. Examples of soft polyesters generally include polyesters obtained from at least an aliphatic monomer component [e.g., an aliphatic diol (e.g., 1,4-butanediol and the aliphatic diols listed in the paragraph of the PBT resin and their reactive derivatives), an aliphatic dicarboxylic acid (e.g., the aliphatic dicarboxylic acids listed in the paragraph of the PBT resin and their reactive derivatives), an aliphatic hydroxycarboxylic acid (e.g., glycolic acid and hydroxycaproic acid), and a lactone listed in the paragraph of the PBT resin]. If necessary, the aliphatic monomer component can be used in combination with a copolymerizable monomer (generally a non-aromatic monomer component, such as an alicyclic diol or an alicyclic dicarboxylic acid and its reactive derivatives).

[0060] Among these soft polyesters, amorphous polyesters such as aliphatic polyesters of aliphatic dicarboxylic acids and aliphatic diols and polylactones (ring-opening polymers of lactones) are preferred. It is sufficient that the soft segment of the polyether-based elastomer has at least a polyether unit. The soft segment may contain a polyether [e.g., an aliphatic polyether having a polyoxyalkylene unit (e.g., a polyoxyalkylene glycol listed in the paragraph of the PBT resin, preferably a poly(C 2-6 Alkylene glycol)] or polyester obtained by using polyether. Among these polyethers, poly C 2-4 Alkylene glycols such as polyethylene glycol, polypropylene glycol or polytetramethylene glycol. The polyester obtained by using polyethers may include polyesters of polyethers (e.g. polyoxyalkylene glycols) and dicarboxylic acids (generally non-aromatic dicarboxylic acids, such as aliphatic or alicyclic dicarboxylic acids and their reactive derivatives listed in the paragraph of PBT resins), and others. Among these soft blocks, polyester soft blocks having at least one selected from polyether units (aliphatic polyether units, polyester units obtained by using aliphatic polyethers) and aliphatic polyester units are preferred.

[0061] In the present invention, specific examples of the thermoplastic polyester elastomer include polyester-based (i.e., polyester-polyester-based) thermoplastic elastomers and polyether-based (i.e., polyester-polyether-based) thermoplastic elastomers. Polyester-based elastomers include, for example, aromatic crystalline polyesters [e.g., poly(C 2-4 The hard segment of the alkylene arylate (especially, a homopolymer having a polybutylene terephthalate unit or a copolymer having a copolymerizable component such as ethylene glycol or isophthalic acid) or a liquid crystal polyester) and the ... 2-6 Alkylene glycol and C 6-12 Polyether-based elastomers include, for example, block copolymers of hard segments and soft segments, wherein the hard segments comprise aromatic crystalline polyesters or liquid crystal polyesters and the soft segments comprise polyethers such as polyoxyethylene C 2-4 Alkylene glycols such as polytetramethylene ether glycol (eg, polyesters of polyoxyalkylene glycol and dicarboxylic acid).

[0062] Among the polyester elastomers, the preferred polyester elastomer comprises (1) a polyalkylene arylate hard block and (2) a polycaprolactone having an oxidized C 2-6 Aliphatic polyethers of alkylene units (e.g. poly(C 2-6Thermoplastic polyester elastomers can be used alone or in combination. In the thermoplastic elastomer, the weight ratio [former / latter] of the hard segment (or hard component) to the soft segment (or soft component) is generally about 10 / 90 to 90 / 10, preferably about 20 / 80 to 80 / 20, and more preferably about 30 / 70 to 70 / 30 (e.g., about 40 / 60 to 60 / 40).

[0063] In the present invention, the thermoplastic elastomer is required to have flexibility (e.g., wire coating), for example, the flexural modulus of the thermoplastic polyester elastomer is preferably not more than 1000 MPa, and is preferably about 50 to 400 MPa (particularly, about 100 to 300 MPa). For this purpose, too small a flexural modulus may cause some problems during the process; on the other hand, in the case of too large a flexural modulus, sufficient flexibility may not be obtained.

[0064] In the present invention, the derivative based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide (DOPO) as the skeleton structure preferably has the following structure:

[0065]

[0066] Wherein, X is -H2C-CH2- or Preferably

[0067] In a preferred embodiment of the present invention, the derivative based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide (DOPO) as the skeleton structure has the following structure:

[0068]

[0069] The flame retardant exists in the halogen-free flame-retardant thermoplastic polyester elastomer composition as a liquid during processing, and its lubricant function facilitates operation; after the composition is formed, it exists in a solid form, is not easy to precipitate, and maintains a long-term flame retardant effect.

[0070] In recent years, additive flame retardants prepared with DOPO as the skeleton have attracted market attention. For example, patents CN101663374B and CN102428091B both disclose a variety of new additive DOPO flame retardants; however, research on patent JP2001270993A shows that too long a link increases the plasticizing properties of the DOPO flame retardant, causing a decrease in the heat deformation temperature of engineering plastic products; the introduction of hydroxyl groups into the DOPO flame retardant leads to a decrease in the thermal stability of the flame retardant, which is not conducive to plastic processing; the introduction of alkoxy groups increases the oxidation performance, which will lead to premature degradation of polymer materials.

[0071] The DOPO selected in the present invention is a derivative of a skeleton structure as a flame retardant, which not only has a good flame retardant effect, but also has high thermal stability and chemical stability, and can overcome the shortcomings of the existing DiDOPO, such as insufficient chemical resistance and strong plasticity.

[0072] The present invention has no particular limitation on the source of the derivative based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide as the skeleton structure, and any commercially available product or self-made product known to those skilled in the art can be used.

[0073] In the present invention, the solid aromatic phosphate preferably has the following structure:

[0074]

[0075] Wherein, n is an integer of 1 to 4, m is an integer of 0 to 6; A is a divalent arylene moiety bonded to two oxygen atoms of any one of hydroquinone, resorcinol, 4,4'-biphenol, bisphenol S or bisphenol F; R1 is selected from one of C1 to C18 alkyl, C3 to C18 heteroaryl, and C6 to C18 aryl.

[0076] Organic phosphate esters, especially aromatic phosphate ester flame retardants, have flame retardant effects in both gas phase and condensed phase, have good carbonization effect, make the flame retardant composition not easy to drip, and meet the market demand of UL 94V0. However, products prepared from compositions containing liquid phosphate esters (such as bisphenol A di(diphenyl phosphate) (BDP) and resorcinol di(diphenyl phosphate) (RDP)) flame retardants undergo migration of phosphate ester flame retardants during long-term use as the surface liquid flame retardant volatilizes, and cannot meet long-term flame retardant needs, especially in the fields of cables and other fields with complex application environments.

[0077] The present invention has no special restriction on the source of the solid aromatic phosphate, and any commercially available product or homemade product known to those skilled in the art may be used.

[0078] In a preferred embodiment of the present invention, the solid aromatic phosphate is preferably hydroquinone bis(diphenyl phosphate) and / or resorcinol bis(di-2,6-dimethylphenyl phosphate), more preferably resorcinol bis(di-2,6-dimethylphenyl phosphate). The melting point of the solid aromatic phosphate flame retardant under ambient conditions is preferably above 50°C, more preferably above 80°C, and even more preferably above 100°C. The solid aromatic phosphate flame retardant exists as a liquid during the processing of the halogen-free flame retardant thermoplastic polyester elastomer composition, so that it acts as a lubricant to improve the material properties; the solid aromatic phosphate flame retardant exists as a solid without precipitation during the normal use of the halogen-free flame retardant thermoplastic polyester elastomer composition.

[0079] In the present invention, the D95 maximum value of the melamine cyanurate is preferably 15 μm. The present invention has no special restrictions on the source of the melamine cyanurate, and any commercially available product or self-made product known to those skilled in the art can be used.

[0080] In the present invention, the auxiliary agent is preferably selected from one or more of antioxidants, processing aids, colorants, ultraviolet stabilizers (including UV absorbers), antistatic agents, nucleating agents, slip agents, plasticizers, lubricants, viscosity control agents, tackifiers, antiblocking agents, surfactants, extender oils, acid scavengers and metal deactivators. The present invention has no particular restrictions on the source of the auxiliary agent, and commercially available products well known to those skilled in the art can be used; these auxiliary agents are usually used in conventional ways and conventional amounts.

[0081] In the present invention, suitable UV light stabilizers preferably include hindered amine light stabilizers (HALS) and UV light absorber (UVA) additives; antioxidants preferably include hindered phenols, such as tetrakis [methylene (3,5-di-tert-butyl-4-hydroxyhydrocinnamate)] methane; bis [(β- (3,5-di-tert-butyl-4-hydroxybenzyl) -methylcarboxyethyl)] sulfide, 4,4'-thiobis (2-methyl-6-tert-butylphenol), 4,4'-thiobis (2-tert-butyl-5-methylphenol), 2,2'-thiobis (4-methyl-6-tert-butylphenol), and thiodiethylene bis (3,5-di-tert-butyl-4-hydroxy) hydrocinnamate; phosphites and phosphonites, such as tris (2,4-di-tert-butylphenyl) phosphite and di-tert-butylphenyl-phosphonite; thio compounds, such as dilauryl thiodipropionate , dimyristyl thiodipropionate, and distearyl thiodipropionate; various siloxanes; polymerized 2,2,4-trimethyl-1,2-dihydroquinoline, N,N'-di(1,4-dimethylpentyl-p-phenylenediamine), alkylated diphenylamine, 4,4'-di(α,α-dimethylbenzyl)diphenylamine, diphenyl-p-phenylenediamine, mixed diaryl-p-phenylenediamines, and other hindered amine antidegradants or stabilizers; the processing aids preferably include metal salts of carboxylic acids, such as zinc stearate or calcium stearate; fatty acids, such as stearic acid, oleic acid, or erucic acid; fatty amides, such as stearamide, oleamide, erucamide, or N,N'-ethylenebisstearamide; polyethylene wax; oxidized polyethylene wax; polymers of ethylene oxide; copolymers of ethylene oxide and propylene oxide; vegetable waxes; petroleum waxes; nonionic surfactants; silicone fluids and polysiloxanes.

[0082] The halogen-free flame-retardant thermoplastic polyester elastomer composition provided by the present invention adopts specific components in specific contents to achieve overall good interaction, and has excellent processing performance and mechanical properties while having excellent flame retardancy.

[0083] The present invention also provides a method for preparing the halogen-free flame-retardant thermoplastic polyester elastomer composition described in the above technical solution, comprising the following steps:

[0084] A thermoplastic polyester elastomer, a derivative based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide as a skeleton structure, a solid aromatic phosphate, melamine cyanurate and an additive are melt-blended, extruded into granules, and then dried and sealed to obtain a halogen-free flame-retardant thermoplastic polyester elastomer composition.

[0085] In the present invention, the thermoplastic polyester elastomer, the derivative based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide as the skeleton structure, the solid aromatic phosphate, the melamine cyanurate and the additives are the same as those in the above technical solution and are not described in detail here.

[0086] In the present invention, the halogen-free flame retardant thermoplastic polyester elastomer composition is a melt-blended mixture, wherein all of the polymer components are well dispersed in each other, and all of the non-polymer components are uniformly dispersed and confined in the polymer matrix, so that the mixture forms a unified whole. In the present invention, any melt-blending method can be used to mix the polymer components and non-polymer components of the composition of the present invention. In the present invention, the temperature of the melt blending is preferably 150° C. to 190° C.

[0087] In the present invention, the drying temperature is preferably 110° C. to 130° C., and the drying time is preferably 5 h to 7 h.

[0088] The preparation method provided by the invention has simple process, mild conditions, easy control and broad application prospects.

[0089] The present invention also provides a product, comprising a component made from the halogen-free flame-retardant thermoplastic polyester elastomer composition described in the above technical solution.

[0090] In the present invention, the products are preferably selected from motor vehicle parts and electrical / electronic devices. In addition, conventional furniture, footwear, roof structures, outdoor clothing, water management systems and other products have lower requirements on components than motor vehicle parts and electrical / electronic devices, and components made of the halogen-free flame retardant thermoplastic polyester elastomer composition described in the above technical solution of the present invention can also be used; it includes at least one component made of the halogen-free flame retardant thermoplastic polyester elastomer composition described in the above technical solution.

[0091] In a preferred embodiment of the present invention, the product is an insulated wire or an insulated cable, which comprises one or more layers of an insulating layer and / or an insulating sheath made of the halogen-free flame-retardant thermoplastic polyester elastomer composition described in the above technical solution.

[0092] In a preferred embodiment of the present invention, the product is an insulated wire or cable, which preferably includes two or three conductive cores, two or three insulating layers each surrounding one of the conductive cores, and an optional insulating sheath surrounding the conductive core and the insulating layer, wherein the insulating layer and / or insulating sheath are made of the halogen-free flame retardant thermoplastic polyester elastomer composition described in the above technical solution of the present invention.

[0093] The present invention can combine the components of the flame retardant mixture by mixing in a blender, a Banbury mixer, a roll mill, or any method known to those skilled in the art for mixing and dispersing chemical compounds, as long as the method does not cause degradation of the components; the components of the flame retardant mixture can also be blended separately with additives and / or thermoplastic elastomers by methods that do not degrade the components of the flame retardant mixture, such as in a Banbury mixer or an extruder. In addition, the polymer components and non-polymer components of the flame retardant polymer composition of the present invention can be added to a melt mixer, such as a single screw extruder or a twin screw extruder; a blender; a single screw kneader or a twin screw kneader; or a Banbury mixer, by adding a single step at the same time, or in a step-by-step manner, and then melt mixing; when adding polymer components and non-polymer components in a step-by-step manner, first add a portion of the polymer components and / or non-polymer components and melt mix, then add the remaining polymer components and non-polymer components and further melt mix until a well-mixed composition is obtained; when a long-length filler such as long glass fiber is used in the composition, pultrusion can be used to prepare an enhanced composition.

[0094] The flame retardant polymer composition can be formed into articles using methods known to those skilled in the art, such as injection molding, blow molding, injection blow molding, extrusion, thermoforming, melt casting, vacuum molding, rotational molding, calendering molding, slush molding, filament extrusion, and fiber spinning. Such articles may include films, fibers and filaments, wire and cable coatings; photovoltaic cable coatings, optical fiber coatings, pipes and ducts; fabrics or textiles made from fibers and filaments, such as those used in clothing or carpets; films and membranes, such as breathable membranes in roofs and buildings / constructions; motor vehicle parts, such as body panels, airbag doors, dashboards, engine hoods, rocker panels, or air filter covers; components for household appliances, such as washers, dryers, refrigerators, and heating-ventilation-air conditioning units; connectors in electrical / electronic applications; components for electronic devices, such as computers; parts for office furniture, indoor furniture, and outdoor furniture; and footwear components.

[0095] The product prepared by using the halogen-free flame-retardant thermoplastic polyester elastomer composition provided by the present invention has good mechanical properties, shows good flame retardancy, and has good mechanical and chemical stability.

[0096] The present invention provides a halogen-free flame-retardant thermoplastic polyester elastomer composition, a preparation method thereof and an application thereof; the halogen-free flame-retardant thermoplastic polyester elastomer composition comprises: 30-90wt% of thermoplastic polyester elastomer; 5-30wt% of derivatives based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide as a skeleton structure; 1-10wt% of solid aromatic phosphate; 2-30wt% of melamine cyanurate; and 0.1-10wt% of an auxiliary agent. Compared with the prior art, the halogen-free flame-retardant thermoplastic polyester elastomer composition provided by the present invention adopts specific components with specific contents to achieve overall good interaction, and has excellent flame retardancy as well as excellent processing performance and mechanical properties. The products prepared by using the halogen-free flame-retardant thermoplastic polyester elastomer composition have good mechanical properties, good flame retardancy, and good mechanical and chemical stability.

[0097] In addition, the preparation method provided by the present invention has simple process, mild conditions, easy control, and broad application prospects.

[0098] In order to further illustrate the present invention, the following examples are provided for detailed description.

[0099] Examples and Comparative Examples

[0100] The following materials are used to prepare the flame-retardant polymer composition described in the embodiments of the present invention and the composition of the comparative example, and can be commercially available sources well known to those skilled in the art or homemade sources using preparation methods well known to those skilled in the art; wherein:

[0101] (a) Thermoplastic polyester elastomer (TPU): a copolyetherester elastomer comprising 44.9 weight percent of poly(tetramethylene oxide) having an average molecular weight of 1000 g / mol as a polyether block segment, the weight percent being based on the total weight of the copolyetherester elastomer, the short-chain ester units of the copolyetherester being polybutylene terephthalate and polybutylene isophthalate segments; the copolyetherester elastomer comprising up to 6 weight percent of heat stabilizers, antioxidants and metal base activators as required by the preparation method and well known to those skilled in the art; prior to use, the TPU sample was predried in vacuum at 90° C. for at least 6 hours.

[0102] (b) 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide (DOPO) derivatives are:

[0103]

[0104] (c) Solid phosphate flame retardant: resorcinol bis(di-2,6-dimethylphenyl phosphate).

[0105] (d) Melamine cyanurate flame retardant: Melamine cyanurate, D95 maximum value is 15μm.

[0106] (e) Conventional auxiliaries: surface-active substances, fillers, further flame retardants, nucleating agents, oxidation stabilizers, lubricating and demoulding aids, dyes and pigments, optional stabilizers (for example against hydrolysis, light, heat or discoloration), inorganic and / or organic fillers, reinforcing agents and plasticizers.

[0107] In the following table, the composition of the Example is identified as "E" and the composition of the Comparative Example is identified as "C".

[0108] See Table 1 below for details.

[0109] Table 1 Raw materials used in preparing halogen-free flame retardant thermoplastic polyester elastomer composition

[0110]

[0111]

[0112] Preparation method:

[0113] According to the raw material formula given in Table 1, a twin-screw extruder was used to prepare and evaluate the extrusion characteristics and key performances. The comparative example (C) and the example of the present invention (E) were used for material preparation and evaluation according to the following steps.

[0114] The above materials in the amounts listed in Table 1 were melt-blended in a twin-screw extruder; the compounded melt-blended mixture was then extruded in the form of a ribbon or strand, the barrel temperature of the extruder being 170°C, the screw diameter being 35.5 mm, the L / D being 38.6, and the output being 20 kg / hr; finally, the obtained pellets were dried at 120°C for 6 hours to obtain composite particles; and the composite particles were placed in a sealed aluminum-lined bag to prevent exposure to external moisture.

[0115] Application Examples

[0116] The above composition is used for preparing cable sheath. In order to evaluate the flame retardancy, the cable is made on a conventional extrusion line (smooth tubular extruder, extruder diameter 45 mm) to obtain the cable insulation and cable sheath; a conventional three-stage screw with a compression ratio of 2.5:1 is used.

[0117] First, the core (8 twisted individual wires) was insulated with each mixture in a tubular process, wherein each mixture was 0.1 mm; the diameter of the insulated core was 1.0 mm; 3 such cores were twisted and a sheath was applied in a tubular process by extrusion (sheath thickness 1 mm); the outer diameter of the entire cable was 5 mm.

[0118] The flammability test was then carried out by performing a vertical burning test on the cables; in each case 3 cables were tested.

[0119] Performance Testing:

[0120] (1) Mechanical properties:

[0121] Mechanical properties were determined as follows: prior to injection molding, the pellets of the flame retardant composition of the present invention and the pellets of the comparative composition prepared according to the above method were dried to provide a pellet composition having a moisture level of less than 0.08 percent; tensile stress at break and elongation at break were measured according to method ISO 527 using injection molded ISO tensile bar 5A specimens having a thickness of 2 mm; the length of the tensile test bar was 75 mm, and the test speed was 50 mm / min.

[0122] (2) Flame retardancy:

[0123] The flammability test was conducted according to the UL94 test standard, 20 mm vertical burning test, by forming test samples from the composition of the present invention and the comparative composition in the form of a test bar having a size of 125 mm long × 13 mm wide and a thickness of 1.6 mm; before injection molding, the particles of the flame retardant composition prepared according to the above method were dried to provide a particle composition having a moisture level of less than 0.08 percent; before measurement, the test sample was conditioned at 23° C. and 50% relative humidity for 48 hours; in the vertical direction, the test sample was clamped on the longitudinal axis of the sample so that the sample The lower end of the sample is 300 mm above the horizontal layer of dry absorbent surgical cotton; a flamethrower producing a 20 mm high blue flame is placed so that the flame is applied centrally to the midpoint of the bottom edge of the sample for 10 seconds; after applying the flame to the sample for 10 seconds, the flamethrower is removed from the sample and the afterburning time t1 is measured; when the afterburning of the test sample stops, the flamethrower is placed under the sample again for another 10 seconds; the flame is then removed from the test sample and the second afterburning time t2 is measured; based on the performance of the material during combustion, the material is classified into V-0, V-1 or V-2 according to the test specifications, V-2 being the minimum requirement classification.

[0124] The test results are shown in Table 2 below.

[0125] Table 2 Test results

[0126] Composition C1 C2 C3 C4 C5 C6 E7 E8 E9 grade V2 V1 V2 V1 V0 V2 V1 V0 V2 Tensile stress at break (MPa) 15 14 14 9 8 4 10 11 8 Elongation at break (%) 400 380 280 200 200 90 230 200 20

[0127] The experimental results show that the results of E7 to E9 using the flame retardant combination of the present invention show that E8 achieved level V-0 in the UL94 test through these combinations, while the combinations with individual flame retardants or most of the comparative examples could not obtain the above results; during or after the fire, the samples from E7 to E9 did not show any dripping, while burning dripping was observed in C1 to C3 and C6; component c achieved the V-0 level (C5) in the TPU resin, but the tensile stress at break was greatly reduced and the hardness was increased, indicating a more brittle behavior; with respect to the total flame retardant content, the E8 composition was more effective and achieved V-0 in the UL94 test; in addition to showing enhanced flame retardancy, the composition of the present invention showed minimal impact on important mechanical properties in almost all cases.

[0128] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A halogen-free flame-retardant thermoplastic polyester elastomer composition, comprising: Thermoplastic polyester elastomer 30-90wt%; 5 to 30 wt% of derivatives based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide as the framework structure; Solid aromatic phosphate 1-10wt%; Melamine cyanurate 2-30wt%; Additives 0.1~10wt%.

2. The halogen-free flame-retardant thermoplastic polyester elastomer composition according to claim 1, characterized in that: The derivative based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide as the skeleton structure has the following structure: Wherein, X is -H2C-CH2- or 3. The halogen-free flame-retardant thermoplastic polyester elastomer composition according to claim 1, characterized in that: The solid aromatic phosphate has the following structure: Wherein, n is an integer of 1 to 4, m is an integer of 0 to 6; A is a divalent arylene moiety bonded to two oxygen atoms of any one of hydroquinone, resorcinol, 4,4'-biphenol, bisphenol S or bisphenol F; R1 is selected from one of C1 to C18 alkyl, C3 to C18 heteroaryl, and C6 to C18 aryl.

4. The halogen-free flame-retardant thermoplastic polyester elastomer composition according to claim 3, characterized in that: The solid aromatic phosphate is hydroquinone bis(diphenyl phosphate) and / or resorcinol bis(di-2,6-dimethylphenyl phosphate).

5. The halogen-free flame-retardant thermoplastic polyester elastomer composition according to claim 1, characterized in that: The D95 maximum value of the melamine cyanurate is 15 μm.

6. The halogen-free flame-retardant thermoplastic polyester elastomer composition according to claim 1, characterized in that: The auxiliary agent is selected from one or more of antioxidants, processing aids, colorants, UV stabilizers, antistatic agents, nucleating agents, slip agents, plasticizers, lubricants, viscosity controllers, tackifiers, antiblocking agents, surfactants, extender oils, acid scavengers and metal deactivators.

7. The halogen-free flame-retardant thermoplastic polyester elastomer composition according to claim 1, characterized in that: The halogen-free flame-retardant thermoplastic polyester elastomer composition consists of the following components: Thermoplastic polyester elastomer 38.5-58.5wt%; 25-30wt% of derivatives based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide as the framework structure; Solid aromatic phosphate 3-5wt%; Melamine cyanurate 10-30wt%; Additives 0.5~1wt%.

8. A method for preparing the halogen-free flame-retardant thermoplastic polyester elastomer composition according to any one of claims 1 to 7, comprising the following steps: A thermoplastic polyester elastomer, a derivative based on 9,10-dihydro-9-oxa-10-phosphaphenanthrene oxide as a skeleton structure, a solid aromatic phosphate, melamine cyanurate and an additive are melt-blended, extruded into granules, and then dried and sealed to obtain a halogen-free flame-retardant thermoplastic polyester elastomer composition.

9. The preparation method according to claim 8, characterized in that: The temperature of the melt blending is 150° C. to 190° C.; the temperature of the drying is 110° C. to 130° C., and the drying time is 5 h to 7 h.

10. A product, characterized in that A component comprising the halogen-free flame-retardant thermoplastic polyester elastomer composition according to any one of claims 1 to 7.

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