EP0925590A1 - Polyurethanes de polyether conducteurs d'electricite - Google Patents

Polyurethanes de polyether conducteurs d'electricite

Info

Publication number
EP0925590A1
EP0925590A1 EP97939714A EP97939714A EP0925590A1 EP 0925590 A1 EP0925590 A1 EP 0925590A1 EP 97939714 A EP97939714 A EP 97939714A EP 97939714 A EP97939714 A EP 97939714A EP 0925590 A1 EP0925590 A1 EP 0925590A1
Authority
EP
European Patent Office
Prior art keywords
prepolymer
diisocyanate
group
isocyanate
polyol
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP97939714A
Other languages
German (de)
English (en)
Inventor
Vincent John Gajewski
Alessandro Genovese
Peter Rahn Nicholl
Vincent Ricci
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Uniroyal Chemical Co Inc
Original Assignee
Uniroyal Chemical Co Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Uniroyal Chemical Co Inc filed Critical Uniroyal Chemical Co Inc
Publication of EP0925590A1 publication Critical patent/EP0925590A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
    • H01B1/06—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of other non-metallic substances
    • H01B1/12—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of other non-metallic substances organic substances
    • H01B1/122—Ionic conductors
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K5/00—Use of organic ingredients
    • C08K5/04—Oxygen-containing compounds
    • C08K5/09—Carboxylic acids; Metal salts thereof; Anhydrides thereof
    • C08K5/098—Metal salts of carboxylic acids

Definitions

  • the present invention is directed to a process for producing conductive and semi-conductive polyurethane materials. More specifically, the present invention is directed to a method of incorporating a conductive moiety into an isocyanate terminated polyalkyleneether polyol prepolymer to provide a polyether polyurethane material that controls electrostatic discharge while retaining its performance properties.
  • Background of the Invention A noteworthy problem in the modern electronic age is the buildup and discharge of static electricity. It has long been known that static charges, which develop between isolated bodies, are discharged when those bodies are brought into close proximity. Potentials as high as 30,000 volts have been reportedly generated by a person walking on a synthetic carpet.
  • Electrostatic discharge (ESD) can affect electronic equipment in which semiconductor devices are used. Particular problems are found in computer systems, telecommunications equipment, guidance systems, medical equipment and in a variety of other industrial environments. Amongst these industrial applications are printing rolls, safety shoe soling, copy machine rolls, and factory vehicle wheels. In factory environments, ESD is a safety concern when sparks from equipment such as trucks can ignite vessels or reactors containing flammable material such as solvents. A static discharge of a few hundred volts can severely damage or ruin expensive electronic equipment or destroy stored computer data.
  • Conductive materials can also be made of inherently conductive polymers.
  • Such conductive polymers include polyacetylene, polyphenylene, and polypyrrole.
  • Dopants such as AsF 3 , substituted quinones, FeCI 3 , HCIO 4 , BF 4 or iodine may be added to improve conductivity.
  • stability and compatibility problems as well as high cost and limited availability have limited the use of these materials for industrial ESD protection.
  • Charge dissipative materials achieve their electrical conductivities through the use of topical chemicals such as antistats. These substances do not normally conduct electricity themselves but absorb moisture from the air which provide conductivity. Typically, these antistats are small molecules which migrate to the surface of the plastic material containing them and provide conductivity through said moisture absorption. The conductivity and ESD protective properties of these materials are therefore dependent on the humidity of the environment. The performance of these materials also decreases over time as the antistat which has migrated to the surface may be lost by evaporation, cleaning, or contact with other objects. Other known materials that are used to protect polyurethanes from
  • ESD are surface active agents, represented by internal electrostatic discharge control additives. Included among these materials are organic salts of sulfur or nitrogen such as cationic ethoxylated amides, tetraalkylammonium methosulfate, and quaternary ammonium compounds. These organic materials possess, limited conductive properties since only small amounts (typically, 1 -2 phr) of the material may be incorporated into the polymer matrix due to the compromising of performance of the polymer.
  • metals are inherently better conductors of electricity than non-metals, due largely to their electronic structures. It would therefore be desirable, in most applications, to have a metal or metallic compound present in the polymer to impart conductivity into the final product.
  • Dispersion of metal salts into a polymer matrix are typically non- homogeneous, thereby producing inconsistency in the conductive properties of the finished polymer product. Since the polymers in use in industrial environments today are organic and non-metallic, successful incorporation of conductive properties by metals or metallic compounds into polymer matrices has not been possible. This is due, in part, to the inherent insolubility or immiscibility of these two classes of substances. Incorporation of a metal ion into an organic polymer has been done by
  • US patent 5,077,330 discloses a conductive polyurethane with antistatic protection from a polyoxyethylene diol, diisocyanate, and dibutyltin bis lauryl mercaptide.
  • European Patent Publication 566 418 A2, October 20, 1 993 discloses conductive polyurethanes made by mixing chain extenders (polyol or polyamine) into an isocyanate-functional prepolymer with a solution of a metal salt.
  • Isocyanate terminated polyester polyol prepolymers are the only polyurethane prepolymers exemplified.
  • These polyester prepolymers when cured into polyurethane elastomers suffer from a number of disadvantages including: susceptibility to hydrolysis since the ester group is susceptible to attack by water causing rapid decline in physical properties. Polyesters further suffer from internal heat buildup when compressed and relaxed repeatedly. This heat buildup causes failure of the part. Polyester-based urethanes also suffer from fungal growth and relatively poor low temperature flexibility.
  • a conductive polymer especially a polyether based polyurethane.
  • these properties in the final products are hydrolysis resistance, excellent low temperature flexibility, fungal growth resistance and excellent hysteresis
  • a method for producing an isocyanate terminated polyalkyleneether polyol prepolymer containing conductive metallic salts in its matrix.
  • the metallic salts may be selected from those known to conduct electricity and whose cations may be represented by copper, aluminum, silver, nickel and the like.
  • the anions of these salts are any of those which form salts with said cations. Typical anions may be represented by halogen, sulfate, phosphate or other such ions.
  • inorganic salts are commonly known to be conductive.
  • the process of this invention incorporates them into the polymer matrix and overcomes the insolubility of the inorganic salt into the organic polymer. Since the salts are not soluble in organic media, particularly polyurethane prepolymer, the process of this invention is a unique and heretofore unknown solution of transforming an organic polymer matrix into an electrically conductive material via an organic carrier.
  • the carrier may be any organic isocyanate-inert material which contains one or more electronegative moieties in its structure. Examples of these carriers include but are not limited to tri (beta- chloropropyDphosphate, tributylphosphate and tributoxyethylphosphate.
  • the process of imparting conductivity may be to any an isocyanate terminated polyalkyleneether polyol prepolymer containing conductive metallic salts.
  • Preferred are TDI- and MDI- terminated polyalkyleneether polyol prepolymers containing conductive metallic salts and those prepolymers cured with polyols and polyamines to form polyurethane and polyurethane/urea products.
  • Aromatic polyisocyanates are well known and are widely used in the preparation of polyurethane and poly urethane/urea elastomers. These isocyanates generally include preferred aromatic isocyanates such as TDI- 2,4-toluene diisocyanate, 2,6-toluene diisocyanate and MDI- 4,4'-methylene bis (phenylisocyanate).
  • aromatic diisocyanates are, for example, toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, naphthalene- 1 ,5-diisocyanate, diphenyl-4,4'- diisocyanate, diphenylmethane-4,4'-diisocyanate, dibenzyl-4,4'- diisocyanate, stilbene-4,4'-diisocyanate, benzophenone-4,4'-diisocyanate, 1 ,3- and 1 ,4-xylene diisocyanates and their mixtures.
  • Aliphatic diisocyanates and triisocyanates may also be employed including 1 ,6-hexamethylene diisocyanate, 1 ,3-cyclohexyl diisocyanate, 1 ,4-cyclohexyl diisocyanate, methylene bis(4-cyclohexyl diisocyanate), the saturated diphenylmethane diisocyanate (known as H 12 MDI), and the like.
  • the diisocyanates are reacted with a long chain (high molecular weight) polyalkyleneether polyol to produce a prepolymer containing free isocyanate groups which then may be chain extended with a short chain (low molecular weight) polyol or aromatic diamine to form a polyurethane or polyurethane/urea elastomer.
  • Long chain, high molecular weight polyols e.g. those having a molecular weight of above
  • the chain extender is generally a short chain polyol, e.g., C 2 -C 10 polyol, or an aromatic diamine.
  • the long chain, high molecular weight polyol provides flexibility and elastomeric properties to the resin, while the short chain polyol or aromatic diamine provides chain extension or cross-links and adds toughness and rigidity to the resulting elastomeric polymer.
  • High molecular weight polyols namely polyalkyleneether polyols having a number average molecular weight of at least 250, are used to prepare the prepolymer of the instant invention.
  • Molecular weight of about 650 to 3000 is preferred, with molecular weight of 1000 being the most preferred.
  • the weight average molecular weight of the high molecular weight polyol may be as high as 10,000 or as low as 250.
  • the preferred polyalkyleneether polyols may be represented by the general formula HO(RO) n H, wherein R is an C, -C 8 branched, straight or cyclic alkylene radical and n is an integer large enough that the polyether polyol has a number average molecular weight of at least 250.
  • polyalkyleneether polyols are well-known components of polyurethane products and can be prepared by the polymerization of cyclic ethers such as alkylene oxides and glycols, dihydroxyethers, and the like by known methods.
  • Polytetramethyleneether glycol (PTMEG) and poly- propyleneether glycol (PPG) are the preferred polyalkyleneether polyols.
  • the total polyalkyleneether polyol blend portion of the instant invention can be combination of high MW polyol, as previously described, and a low molecular weight polyol.
  • An aliphatic glycol is the preferred low molecular weight polyol. Suitable aliphatic polyols are ethylene glycol, diethylene glycol, dipropylene glycol, neopentyl glycol, 1 , 3-butanediol, 1 ,4-butanediol, and the like.
  • the most preferred low molecular weight polyol is 1 ,4-butanediol.
  • the weight of the low molecular weight polyol should be no more than 20% of the combination of high molecular weight polyol and low molecular weight polyol. A preferred range is 0 to 1 5% of the combination.
  • the prepolymers are prepared by reacting an isocyanate compound with a polyol or polyol blend, maintaining the temperature from room temperature to temperatures as high as 1 50°C for times necessary to react all the available hydroxyl groups. Preferred reaction temperatures are 50°C to 100°C; more preferred are 50°C to 85°C.
  • the product is poured into containers under a nitrogen flush and stored at room temperature.
  • the curative used for the prepolymer can be selected from a wide variety of conventional and well known aliphatic or aromatic polyamine or polyol materials.
  • Aromatic diamines are, for example, 4,4'-methylene bis(2-chloroaniline), 2,2',5-trichloro-4,4'methylenediamines, naphthalene- 1 ,5-diamine, ortho, meta, and para-phenylene diamines, toluene-2,4- diamine, dichlorobenzidine, diphenylether-4,4'-diamine, including their derivatives and mixtures.
  • These diamines or polyols are generally the present ones used in the industry as curatives for polyurethane.
  • the selection of a curative is generally based on reactivity needs, or property needs for a specific application, process condition needs, and pot life desired.
  • Known catalysts may be used in conjunction with the curative if desired. Representative of the most preferred materials are:
  • the stoichiometric ratio of isocyanato groups to hydroxyl groups of the prepolymer depends on which specific isocyanate and polyol are selected. For example, with TDI and PTMEG the ratio of isocyanato groups to hydroxyl groups should preferably be from 1 .3/1 to 2.5/1 although somewhat lower and higher ratios are permissible. When the ratio is much lower, the molecular weight of the isocyanato terminated polyurethane becomes so large that the viscosity of the mass makes mixing of chain extenders into the prepolymer relatively more difficult.
  • a ratio of 2 isocyanato groups to one hydroxyl group is the theoretical ratio for the end-capping of a polyalkyleneether or ester polyol with a diisocyanate.
  • An excess of the 2/1 ratio will result in high levels of free diisocyanate in the mixture but may be removed by distillation or chemical stripping as are conventionally practiced in the art to yield low free isocyanate prepolymers. Therefore, the preferred range is 1 .6/1 to 2.00/1 .
  • the number of -NH 2 groups in the aromatic diamine component should be approximately equal to the number of -NCO groups in the prepolymer.
  • a small variation is permissible but in general from about 80 to 1 20% of the stoichiometric equivalent should be used, preferably about 85 to 100%.
  • the reactivity of isocyanato groups with amino groups varies according to the structure to which the groups are attached. As is well known, as for example in U.S. Patent 2,620,516, some amides react very rapidly with some isocyanates while others react more slowly. In the latter case, it is optional to use catalysts.
  • the temperature of the reaction or of the polyurethane reactant will need only be controlled in order to obtain the proper reaction time; thus, for a diamine that ordinarily would be too reactive, a catalyst would obviously be unnecessary, a lowering of the reaction temperature would suffice.
  • a great variety of catalysts is available commercially for accelerating the reaction of the isocyanato groups with compounds containing active hydrogen atoms (as determined by the well-known Zerewitinoff test). It is well within the skill of the technician in this field to pick and choose catalysts to fit his particular needs or desires and adjust the amounts used to further refine his conditions.
  • Adipic acid and triethylene diamine are typical of suitable catalysts.
  • the isocyanate:polyol stoichiometric ratios range typically from 2: 1 to 5: 1 .
  • An even more preferred range of stoichiometric ratio of isocyanate:polyol would be from 3: 1 to 4: 1 .
  • Other isocyanates and polyols will require different ratios but these are well-known to those skilled in the art and may be adjusted to fit particular requirements.
  • Such properties as tensile, tear, hardness, and modulus are highly designable through selection of various polyol, isocyanate, and curative types. Incorporation of branched polyols or more highly functional isocyanates allows for modification of crosslinking. Urethane polymerizations based on longer-chain polyols result in more flexible elastomeric products.
  • vulcanizate hardnesses ranging from 1 5 durometer A to 75 durometer D can be obtained. Compounding with fillers, plasticizers, and other agents may be done to control a broad range of properties.
  • Urethane elastomers generally provide toughness, weatherability, and long wear as well as a combination of hardness and elasticity.
  • the materials have high tensile and tear strength, high abrasion resistance, and excellent oil, oxygen, ozone, and radiation resistance. They retain a high degree of elasticity and resilience, even at high hardness and over a wide temperature range.
  • the urethanes of the instant invention also use a carrier to incorporate a conductive metallic salt into the polymer matrix.
  • carrier as it is used herein will mean a material in which the inorganic metallic compound is soluble and is miscible in the polymer matrix.
  • the carrier may be any organic substance which has one or more electronegative moieties in its structure. Representative of this type of carrier are tri(beta-chloropropyl)phosphate, tributylphosphate, tributoxyethylphosphate and the like.
  • the presence of the conductive metallic material in the carrier does not impact or in any way affect the properties of the polymer product.
  • the examples of the present invention provide conveniently prepared, charge dissipative polymers with a surface resistivity of 10 1 1 to 1 0 6 ohms to provide permanent antistatic protection for a wide variety of commercially useful applications.
  • the conductive properties become part of the cured polymer and as such are a property of the finished product made from the polymer. It can also be seen from the data that the urethane products which possess a three-fold or as high as a ten-fold level of reduced resistivity (from 10 12 to > 10 9 and from 10 17 to > 10 7 ) retain satisfactory performance as expressed by their physical properties.
  • Example 1 Preparation of Polyurethane Prepolymer from 4,4'- Diphenylmethane Diisocyanate (MDI) and Polytetramethylene Ether GIvcol (PTMEG)
  • MDI 4,4'- Diphenylmethane Diisocyanate
  • PTMEG Polytetramethylene Ether GIvcol
  • a polyurethane prepolymer was prepared by reacting three moles of MDI with one mole of a PTMEG diol of molecular weight 2000. The excess isocyanate content of this reaction was 6.1 % by weight.
  • a one percent (by weight) solution of cup ⁇ c chloride (CuCI 2 ) was prepared by dissolving it in tri(betachloropropyl)phosphate.
  • a polyurethane prepolymer was prepared by reacting 2 moles of TDI with one mole of PTMEG diol of 1000 molecular weight. The resulting prepolymer had an excess isocyanate content of 6.3%.
  • a 10% solution of cupric chloride (CuCI 2 ) was prepared in tributylphosphate. This solution was added to the prepolymer at 10 and 1 5 phr. The appropriate amount ( 1 9 grams) of 4,4'-methylene bis 2-chloroaniline (MBOCA) as a curing agent was then added to cure the prepolymer/cupric chloride mixture.
  • MOCA 4,4'-methylene bis 2-chloroaniline

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Polyurethanes Or Polyureas (AREA)

Abstract

L'invention se rapporte à un procédé de fabrication d'un élastomère de polyuréthane conducteur d'électricité à partir d'un prépolymère de polyol de polyéther. Ledit procédé consiste à mélanger un prépolymère de polyol de polyalkylèneéther à terminaison isocyanate, de préférence un polyol de polyalkylèneéther à terminaison TDI ou MDI, avec des sels métalliques conducteurs, tels que du CuCl2 dispersé dans un porteur miscible avec un prépolymère, de préférence du tri(bétachloropropyl)phosphate. On obtient ainsi un polymère durci avec une bonne conductivité, qui conserve toutes ses propriétés.
EP97939714A 1996-09-12 1997-08-29 Polyurethanes de polyether conducteurs d'electricite Withdrawn EP0925590A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US71274096A 1996-09-12 1996-09-12
US712740 1996-09-12
PCT/US1997/015349 WO1998011562A1 (fr) 1996-09-12 1997-08-29 Polyurethanes de polyether conducteurs d'electricite

Publications (1)

Publication Number Publication Date
EP0925590A1 true EP0925590A1 (fr) 1999-06-30

Family

ID=24863365

Family Applications (1)

Application Number Title Priority Date Filing Date
EP97939714A Withdrawn EP0925590A1 (fr) 1996-09-12 1997-08-29 Polyurethanes de polyether conducteurs d'electricite

Country Status (3)

Country Link
EP (1) EP0925590A1 (fr)
CA (1) CA2265876A1 (fr)
WO (1) WO1998011562A1 (fr)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1507812A1 (fr) * 2002-05-24 2005-02-23 Crompton Corporation Dispersions de polyurethanne

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62139628A (ja) * 1985-12-13 1987-06-23 タキロン株式会社 イオン導電性高分子粘着剤
JPH0733494B2 (ja) * 1990-08-01 1995-04-12 株式会社タジマ プラスチック製床材の導電化方法
US5639847A (en) * 1995-05-25 1997-06-17 Mearthane Products Corp. Preparation of conductive polyurethanes using a conductive quasi-solution

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9811562A1 *

Also Published As

Publication number Publication date
WO1998011562A1 (fr) 1998-03-19
CA2265876A1 (fr) 1998-03-19

Similar Documents

Publication Publication Date Title
US4507459A (en) Polyurethane compositions having low hysteresis
KR100275076B1 (ko) 4,4'-메틸렌-비스-(3-클로로-2,6-디에틸아닐린)으로 경화된 폴리우레탄
EP0194452B1 (fr) Polyester-polyurethane et procédé de sa préparation
US3087912A (en) Process for the production of crosslinked plastics of high molecular weight
JP3073023B2 (ja) トリモーダルの分子量を有するポリエーテルポリオールプレポリマー
CA1239729A (fr) Elastomeres de polyurethane derives de p-tmxdi, possedant de bonnes proprietes de deformation par compression
EP0288823A1 (fr) Procédé pour la préparation de prépolymères de polyisocyanate et de polyuréthanes à résistance élevée à la chaleur et à basse hystérésis
EP2115033B1 (fr) Poly(uréthane)
GB2046281A (en) Process for producing polyurethane elastomer
EP3484937A1 (fr) Uréthanes coulés fabriqués à partir d'un prépolymère de monomère à faible teneur en monomères libres avec un squelette de polycarbonate
US20050020767A1 (en) High performance aqueous polyurethanes dispersion and methods of fabricating the same
CA1330374C (fr) Caoutchoucs de polyurethane reticulables contenant des unites polyoxypefluoroalkylene
US8324315B2 (en) Aqueous aromatic polyurethane elastomeric articles and method of fabricating the same
EP0369389A1 (fr) Polyuréthane-urées dispersables dans l'eau préparées à l'aide de mélanges de diisocyanates
CA1236261A (fr) Pneus en polyurethane arme
US4194940A (en) Method of bonding employing an adhesive composition containing polyisocyanate reaction products having an available isocyanate content of not more than 0.5 percent
US4463155A (en) Polyether polyurethane elastomers
WO2002004536A2 (fr) Compositions urethane modifiees contenant des adduits de polyols d'ester d'anhydride $i(o)-phtalique
WO1998011562A1 (fr) Polyurethanes de polyether conducteurs d'electricite
US3475384A (en) Fluorine-containing polyurethane
EP0372418A2 (fr) Un procédé pour la préparation de polymères antistatiques à partir de polyisocyanates en incorporant un mélange d'un sel et d'un carbonate polyalkylène
EP4028446B1 (fr) Composition de polyuréthane thermoplastique
US5166299A (en) Polyurethanes comprising the reaction product of an isocyanate prepolymer and isomers of di(methylthio)-diaminotoluene
US20220315692A1 (en) Waterborne polyurethane
EP0817808B1 (fr) Systemes permettant d'obtenir par vulcanisation des elastomeres de polyurethane

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19990224

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

17Q First examination report despatched

Effective date: 19990727

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20000208