CN104211895B - Flame-retardant wear-resistant pressure-resistant polyurethane floor material and preparation method thereof - Google Patents

Flame-retardant wear-resistant pressure-resistant polyurethane floor material and preparation method thereof Download PDF

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Publication number
CN104211895B
CN104211895B CN201410477866.1A CN201410477866A CN104211895B CN 104211895 B CN104211895 B CN 104211895B CN 201410477866 A CN201410477866 A CN 201410477866A CN 104211895 B CN104211895 B CN 104211895B
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Prior art keywords
resistant
parts
floor material
flame
wear
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CN201410477866.1A
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CN104211895A (en
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何建雄
王良
王一良
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Dongguan City Ji Xin Macromolecule Science And Technology Ltd
Dongguan Xionglin New Materials Technology Co Ltd
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Dongguan City Ji Xin Macromolecule Science And Technology Ltd
Dongguan Xionglin New Materials Technology Co Ltd
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    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00Polymeric products of isocyanates or isothiocyanates
    • C08G18/06Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/70Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the isocyanates or isothiocyanates used
    • C08G18/72Polyisocyanates or polyisothiocyanates
    • C08G18/74Polyisocyanates or polyisothiocyanates cyclic
    • C08G18/76Polyisocyanates or polyisothiocyanates cyclic aromatic
    • C08G18/7614Polyisocyanates or polyisothiocyanates cyclic aromatic containing only one aromatic ring
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00Polymeric products of isocyanates or isothiocyanates
    • C08G18/06Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/28Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
    • C08G18/40High-molecular-weight compounds
    • C08G18/48Polyethers
    • C08G18/4804Two or more polyethers of different physical or chemical nature
    • C08G18/4812Mixtures of polyetherdiols with polyetherpolyols having at least three hydroxy groups
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00Polymeric products of isocyanates or isothiocyanates
    • C08G18/06Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/70Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the isocyanates or isothiocyanates used
    • C08G18/72Polyisocyanates or polyisothiocyanates
    • C08G18/74Polyisocyanates or polyisothiocyanates cyclic
    • C08G18/76Polyisocyanates or polyisothiocyanates cyclic aromatic
    • C08G18/7614Polyisocyanates or polyisothiocyanates cyclic aromatic containing only one aromatic ring
    • C08G18/7628Polyisocyanates or polyisothiocyanates cyclic aromatic containing only one aromatic ring containing at least one isocyanate or isothiocyanate group linked to the aromatic ring by means of an aliphatic group
    • C08G18/7642Polyisocyanates or polyisothiocyanates cyclic aromatic containing only one aromatic ring containing at least one isocyanate or isothiocyanate group linked to the aromatic ring by means of an aliphatic group containing at least two isocyanate or isothiocyanate groups linked to the aromatic ring by means of an aliphatic group having a primary carbon atom next to the isocyanate or isothiocyanate groups, e.g. xylylene diisocyanate or homologues substituted on the aromatic ring
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G18/00Polymeric products of isocyanates or isothiocyanates
    • C08G18/06Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
    • C08G18/70Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the isocyanates or isothiocyanates used
    • C08G18/72Polyisocyanates or polyisothiocyanates
    • C08G18/74Polyisocyanates or polyisothiocyanates cyclic
    • C08G18/76Polyisocyanates or polyisothiocyanates cyclic aromatic
    • C08G18/7657Polyisocyanates or polyisothiocyanates cyclic aromatic containing two or more aromatic rings
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09DCOATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D175/00Coating compositions based on polyureas or polyurethanes; Coating compositions based on derivatives of such polymers
    • C09D175/04Polyurethanes
    • C09D175/08Polyurethanes from polyethers
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09DCOATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D5/00Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
    • C09D5/18Fireproof paints including high temperature resistant paints
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L2201/00Properties
    • C08L2201/02Flame or fire retardant/resistant

Abstract

The invention relates to a flame-retardant wear-resistant pressure-resistant polyurethane floor material and a preparation method thereof. The polyurethane floor material comprises the following components in parts by weight: 18-40 parts of polyether dibasic alcohol, 13-25 parts of polyether tribasic alcohol, 8-30 parts of polyisocyanate, 6-12 parts of ammonium polyphosphate, 3-10 parts of melamine, 2-8 parts of pentaerythritol and 0.3-1 part of dibutyltin dilaurate. The preparation method comprises the following steps: mixing the polyether dibasic alcohol and polyether tribasic alcohol according to the formula, adding the ammonium polyphosphate, melamine and pentaerythritol, and continuing mixing; and adding the polyisocyanate and dibutyltin dilaurate into the uniform mixture, and continuing mixing uniformly to obtain the flame-retardant wear-resistant pressure-resistant polyurethane floor material. The flame-retardant wear-resistant pressure-resistant polyurethane floor material has the advantages of accessible raw materials, simple preparation method and environment friendliness. Compared with the double-component polyurethane floor material, the flame-retardant wear-resistant pressure-resistant polyurethane floor material has favorable flame retardancy, wear resistance and pressure resistance, and can obviously improve the use effect of the floor paint.

Description

Wear-resisting pressure polyurethane terrace material of a kind of flame retardant type and preparation method thereof
Technical field
The present invention relates to polyurethane terrace material preparing technical field, and in particular to a kind of wear-resisting pressure polyurethane of flame retardant type Floor material and preparation method thereof.
Background technology
At present, the polyurethaness floor material for producing on market is bi-component air-curing coatings, by elastic polyurethane Prepolymer first component and mixed the second component for constituting by hydroxy-containing resin component and pigment, auxiliary agent etc. and constituted, during construction by first, Second component is mixed in proportion, crosslinking coatings film-forming after application, the resilient colour ground film of tool is formed, with excellent Elasticity, adhesive force and wearability, are that senior machine room, laboratory, stadiums, ultra-clean Factory Building, and meeting room, cinema etc. are each Plant and require the resilient industry of tool and the good selection of civil buildings ground coating.But, this kind of bi-component polyurethane esters ground Coating coating in level ground is inflammable product, there is larger disaster hidden-trouble, is particularly useful for flooring, need before construction accurate measurement and Burden process, using inconvenience, abnormal smells from the patient is big.
CN 1765950A disclose a kind of polyurethane elastomer for sports field and preparation method thereof, by following elasticity Body first component, second component and the third component composition, wherein first component are 1 with the weight ratio of second component:2-1:4, the percentage of the third component Than with the gross weight meter of first, second component, wherein first component is consisted of:Methyl diphenylene diisocyanate, polyether Glycols, illiteracy are de- Soil;Second component is consisted of:Polyether-tribasic alcohol, 3,5 dichloros are to trifluoromethyl ethyl phenyl ether, chlorinated paraffin, Pulvis Talci, calcium oxide, ferrum Red or lemon yellow-phthalocyanine green mixture, pentachlorophenol;Third component is consisted of:Waste rubber grain, metallic catalyst.
CN 102134442A disclose a kind of compound method of single-component flame retardant polyurethane floor coating, and this method includes Raw material ratio and production technology.
Polyurethane terrace material of the prior art is difficult to accomplish that the various aspects of performance such as anti-flammability, wearability, resistance to pressure are equal It is very excellent.
The content of the invention
It is an object of the invention to provide wear-resisting pressure polyurethane terrace material of a kind of flame retardant type and preparation method thereof.
It is that, up to this purpose, the present invention is employed the following technical solutions:
A kind of wear-resisting pressure polyurethane terrace material of flame retardant type, the polyurethane terrace material includes by weight following Composition:
The parts by weight of the polyether Glycols may be selected 18.02~38.9,19.6~35,21~32.5,26~30, 28.5 etc., all can be used to implement the present invention.
The parts by weight of the polyether-tribasic alcohol may be selected 13.02~24.8,15~22.4,16.8~20,19.5 etc., all Can be used to implement the present invention.
The parts by weight of the polyisocyanates may be selected 8.03~28.9,10~26,13~24.7,16~22,18.6 Deng, all can be used for implement the present invention.
The parts by weight of the APP may be selected 6.03~11.8,6.7~10.4,7.3~9,8.4 etc., all can use It is of the invention in implementing.
The parts by weight of the tripolycyanamide may be selected 3.04~9.6,3.6~9,5~8.4,5.6~8,6.3~7,6.8 Deng, all can be used for implement the present invention.
The parts by weight of the tetramethylolmethane may be selected 2.03~7.9,2.6~7,3.5~6.4,4~6,5.3 etc., all may be used For implementing the present invention.
The parts by weight of the dibutyl tin laurate may be selected 0.31~9.9,0.8~9.2,1.5~8.6,3~8, 4.3~6.5,5~6,5.2 etc., all can be used to implement the present invention.
The present invention is respectively the poly- of catalyst, carbon forming agent and foaming agent using polyphosphoric acid amine, tripolycyanamide and tetramethylolmethane The flame-retardant system of urethane floor material, makes coating have good fire resistance.
The polyether Glycols are polyoxypropylene dihydroxylic alcohols.
The polyether-tribasic alcohol is glycerol polyoxypropylene.
The polyisocyanates includes toluene di-isocyanate(TDI), methyl diphenylene diisocyanate, the Carbimide. of 1,5- naphthalenes two Ester, XDI, 3,3 '-dimethyl -4,4- biphenyl diisocyanates, triphenylmethane triisocyanate or One kind or at least two mixture in PPDI.Typical but non-limiting example includes:Toluene diisocyanate Acid esters, methyl diphenylene diisocyanate, 1,5- naphthalene diisocyanate, XDI, 3,3 '-dimethyl- 4,4- biphenyl diisocyanates, XDI and 3,3 '-dimethyl -4,4- biphenyl diisocyanates, triphen Methylmethane triisocyanate and PPDI, toluene di-isocyanate(TDI), methyl diphenylene diisocyanate and 1,5- naphthalene Diisocyanate, 1,5- naphthalene diisocyanate, XDI, PPDI and diphenyl methane two Isocyanates etc., all can be used to implement the present invention.
Used as the preferred technical solution of the present invention, the polyurethane terrace material includes by weight following component:
Used as most preferably technical scheme of the invention, the polyurethane terrace material includes by weight following component:
" including " of the present invention, it is intended that it can also include other components, these other components in addition to the component Give the polyurethane terrace material different characteristics.In addition, " including " of the present invention, may be replaced by closing " being " of formula or " by ... constitute ".
A kind of preparation method of described polyurethane terrace material, the method comprising the steps of:
1) APP, tripolycyanamide and season will be added after polyether Glycols and polyether-tribasic alcohol stirring mixing by formula ratio Penta tetrol continues to mix;
2) to step 1) in add polyisocyanates and dibutyl tin laurate in the material that stirs, continue to stir Mix homogeneously obtains the wear-resisting pressure polyurethane terrace material of flame retardant type.
Compared with prior art scheme, the invention has the advantages that:
The wear-resisting pressure polyurethane terrace material raw material of flame retardant type of the present invention is easy to get, and preparation method is simple, the feature of environmental protection It is good, compared with existing two component polyurethane floor material, with good anti-flammability, wearability and resistance to pressure, can substantially change Kind polyurethaness floor coatings using effect.
Below the present invention is described in more detail.But following examples is only the simple example of the present invention, not generation Table limits the scope of the present invention, and protection scope of the present invention is defined by claims.
Specific embodiment
Technical scheme is further illustrated below by specific embodiment.
For the present invention is better described, technical scheme is readily appreciated, the present invention's is typical but non-limiting Embodiment is as follows:
Embodiment 1
A kind of wear-resisting pressure polyurethane terrace material of flame retardant type, the polyurethane terrace material includes by weight following Composition:
1) APP, tripolycyanamide and season will be added after polyether Glycols and polyether-tribasic alcohol stirring mixing by formula ratio Penta tetrol continues to mix;
2) to step 1) in add polyisocyanates and dibutyl tin laurate in the material that stirs, continue to stir Mix homogeneously obtains the wear-resisting pressure polyurethane terrace material of flame retardant type.
Embodiment 2
A kind of wear-resisting pressure polyurethane terrace material of flame retardant type, the polyurethane terrace material includes by weight following Composition:
Its preparation method is with embodiment 1.
Embodiment 3
A kind of wear-resisting pressure polyurethane terrace material of flame retardant type, the polyurethane terrace material includes by weight following Composition:
Its preparation method is with embodiment 1.
Embodiment 4
A kind of wear-resisting pressure polyurethane terrace material of flame retardant type, the polyurethane terrace material includes by weight following Composition:
Its preparation method is with embodiment 1.
Embodiment 5
A kind of wear-resisting pressure polyurethane terrace material of flame retardant type, the polyurethane terrace material includes by weight following Composition:
Its preparation method is with embodiment 1.
Comparative example
Using the embodiment disclosed in CN 102134442A as comparative example of the invention.
It is right that the anti-flammability of embodiment of the present invention 1-5 and comparative example, wearability and resistance to pressure test result are carried out in table 1 Than.
The performance comparison table of each embodiment of table 1 and comparative example
Applicant state, person of ordinary skill in the field on the basis of above-described embodiment, by above-described embodiment The concrete content point value of component, it is combined with the technical scheme of Summary, so as to the new numerical range for producing, be also One of record scope of the present invention, the application no longer enumerates these numerical rangies to make description simple and clear.
The preferred embodiment of the present invention described in detail above, but, the present invention is not limited in above-mentioned embodiment Detail, the present invention range of the technology design in, various simple variants can be carried out to technical scheme, this A little simple variants belong to protection scope of the present invention.
It is further to note that each particular technique feature described in above-mentioned specific embodiment, in not lance In the case of shield, can be combined by any suitable means, in order to avoid unnecessary repetition, the present invention to it is various can The compound mode of energy is no longer separately illustrated.
Additionally, combination in any can also be carried out between a variety of embodiments of the present invention, as long as it is without prejudice to this The thought of invention, it should equally be considered as content disclosed in this invention.

Claims (2)

1. the wear-resisting pressure polyurethane terrace material of a kind of flame retardant type, it is characterised in that the polyurethane terrace material is by weight Number includes following component:
2. a kind of preparation method of polyurethane terrace material as claimed in claim 1, it is characterised in that methods described include with Lower step:
1) APP, tripolycyanamide and season penta 4 will be added after polyether Glycols and polyether-tribasic alcohol stirring mixing by formula ratio Alcohol continues to mix;
2) to step 1) in add polyisocyanates and dibutyl tin laurate in the material that stirs, continue to stir mixing Uniformly obtain the wear-resisting pressure polyurethane terrace material of flame retardant type.
CN201410477866.1A 2014-09-18 2014-09-18 Flame-retardant wear-resistant pressure-resistant polyurethane floor material and preparation method thereof Active CN104211895B (en)

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Families Citing this family (2)

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CN106639236B (en) * 2016-11-28 2019-02-26 河南同伟建材有限公司 A kind of elastic brick and preparation method thereof for accomodation ground
CN107057022A (en) * 2017-03-31 2017-08-18 苏州铂邦胶业有限公司 A kind of novel flexible gravity flowing levelling mortar terrace and preparation method thereof

Family Cites Families (3)

* Cited by examiner, † Cited by third party
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WO2005033232A1 (en) * 2003-10-02 2005-04-14 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e. V. Composition for a fire-protection agent for materials and fire-protection method
CN102585293B (en) * 2011-01-14 2013-10-16 中国林业科学研究院木材工业研究所 Flame retardant, and preparation method and application thereof
CN103980810A (en) * 2014-05-19 2014-08-13 上海正欧实业有限公司 Waterproof solvent-free single-component polyurethane lacquer used on wet surface and preparation method thereof

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
聚氨酯复合材料的研究;康永等;《PU技术》;20101231(第101期);第64-66页 *
聚醚N220、N330 的合成条件研究;钱亚杰;《天津化工》;20081231;第22卷(第4期);第46-47页 *

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