Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
  • C08J5/12—Bonding of a preformed macromolecular material to the same or other solid material such as metal, glass, leather, e.g. using adhesives
  • C08J5/124—Bonding of a preformed macromolecular material to the same or other solid material such as metal, glass, leather, e.g. using adhesives using adhesives based on a macromolecular component
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G8/00—Condensation polymers of aldehydes or ketones with phenols only
  • C08G8/02—Condensation polymers of aldehydes or ketones with phenols only of ketones
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G8/00—Condensation polymers of aldehydes or ketones with phenols only
  • C08G8/04—Condensation polymers of aldehydes or ketones with phenols only of aldehydes
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J161/00—Adhesives based on condensation polymers of aldehydes or ketones; Adhesives based on derivatives of such polymers
  • C09J161/04—Condensation polymers of aldehydes or ketones with phenols only
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2377/00—Characterised by the use of polyamides obtained by reactions forming a carboxylic amide link in the main chain; Derivatives of such polymers

Definitions

• This invention relates to resin compositions having particular use for joining nylon pipes.
• polyamide plastics and in particular of various nylon plastics for a variety of engineering applications.
• An example is the use of Nylon 11 for pipes employed in gas distribution.
• the adhesive currently favoured for connecting Nylon 11 gas pipes is a solution of Nylon 11 in m-cresol. M-cresol is toxic and is absorbed rapidly through the skin and by inhalation. Other solvent in which Nylon is sufficiently soluble at ambient temperature tend to be corrosive or toxic.
• an adhesive system which is non-toxic, which is gap filling when cured, which has a long shelf life and for preference which is a one part system or less preferably is a two part system in which the parts have a long pot life after mixing.
• the adhesive should result in a bond capable of passing pipe joint quality tests within 10 to 20 minutes of application and be resistant to environmental damage.
• An object of the present invention is to provide an improved method of, and compositions for, joining nylon pipes. Resins believed to be novel have been developed with that objective in view and those resins have novel properties suiting them for other purposes. DISCLOSURE OF INVENTION
• the invention consists in a method for manufacture of a resin comprising the steps of causing to react
• the invention also resides in a resin made by the method and in a method of joining parts by use of an adhesive including the resin.
• phenol is herein used generically and includes monohydric and polyhydric phenols.
• the phenol is a dihydric phenol, more preferably resorcinol, and is reacted with cyclohexanone (a cyclic ketone having 6 ring carbons) to form a curable resin.
• the resin may be used as a two part adhesive by the addition of a curing agent, for example, paraformaldehyde or diamine, or the resin may be cured by reaction with the amine groups of nylon and thus may be used as a single part adhesive for connecting nylon components or pipes.
• a curing agent for example, paraformaldehyde or diamine
• a phenol or substituted phenol having a labile ring hydrogen is caused to react with a cyclic ketone or a dialdehyde having at least 6 carbon atoms.
• Resorcinol is preferred as the phenol.
• other polyhydric phenols and substituted phenols which predictably have a labile proton on the ring group, may be used.
• the reaction is performed in ethanol (99.7 to 100% V/V) and the resin is formed by reaction of resorcinol and cyclohexanone.
• the reaction may be conducted under acid or alkaline conditions.
• the means of controlling pH of the reaction mixture should be selected so as not to interfer with the reaction.
• Oxalic Acid dihydrate HO 2 CCO 2 H.2H 2 O
• the reaction is generally conducted under reflux.
• a catalyst has been found to be desirable to reduce reaction times and to improve resin quality.
• Some of the compounds which catalyse the reaction include Lewis Acids (such as A1C1 3 or FeCl 3 ), and organometallic compounds made from metal/resoncinol mixtures. These organometallics include compounds based on single or a combination of metals in combination with resorcinol. Up to 10 metals have been combined into one organometallic catalyst.
• the catalysts produced have a wide range of activities.
• the metals used include mercury, zinc, tin, iron, manganeze, cobalt, lead, nickel and aluminium in concentrations varying between 1 ppm and 3,500 ppm (concentration of metal to final resin). Differences in reaction rates and quality of the final resin varies with the quantity and type of catalyst used.
• EXAMPLE 1 A solution of resorcinol (50 g) in ethanol (50 ml) was heated to reflux and a solution of oxalic acid dehydrate (1.4 g) in water (9 ml) was added slowly. Cyclohexanone (approx. 33.4g 0.34M to 42.4g 0.43M) was then added dropwise. The mixture was refluxed a further 4 hours. The solvent and water of condensation were then removed and the resin product dissolved in ethanol to yield a 25-50% w/w solution.
• the resin was an alcohol soluble brown polymer which may precipitate as an oil, and which does not form crystals visible to the naked eye.
• Table 1 shows various compositions according to the invention.
• the compositions were made by the method described but differed from each other in respect of the ratio by weight of cyclohexanone to resorcinol, the reflux time, and the pH of reaction.
• a filler or hardener was included in some samples.
• Table 2 is similar to Table 1 but includes resins according to the invention wherein one or more catalysts were used in the manufacture of the resin.
• Catalyst type A is to a mixed metal solution of which the composition is shown in Example 5 hereinafter and catalyst type B is a mixed metal catalyst isolated as in Example 6 hereinafter.
• EXAMPLE 5 Example of Mixed Metals Catalyst for use in manufacture of resins according to the invention. Solution in one litre of water
• the catalyst was degassed with N 2 before use.
• EXAMPLE 6 Example of Mixed Metal Organometalic Catalyst for use in manufacture of resins according to the invention.
• Resorcinol 25g
• similarly treated ethanol 50ml
• the solution was heated to reflux under N 2 .
• Metal solution 25ml at the concentration listed in Example 5
• Resins according to the invention may be cured with a suitable curing agent for example formaldehyde (e.g. solid paraformaldehyde) or an amine (e.g. hexamine).
• a suitable curing agent for example formaldehyde (e.g. solid paraformaldehyde) or an amine (e.g. hexamine).
• formaldehyde e.g. solid paraformaldehyde
• an amine e.g. hexamine
• the resins may be cured by means of the amine groups of a nylon.
• the resins may thus be used is a single part adhesive for nylon. As a single part adhesive the resin has excellent shelf life. If solvent evaporates from the pot, the adhesive can be reactivated by the addition of solvent. The resin cures in contact with nylon but remains more soluble after curing than the two part adhesive system.
• the resin When used as a two part system, i.e. with the addition of a curing agent, the resin has its greatest gap filling and strength properties.
• a typical pot life after adding curing agent is about 5 hrs. at 22°C.
• the resins were formulated for use as adhesives suitable for forming joints in nylon pipe systems.
• Tables 1 and 2 The data on tensile strength and pressure at failure shown in Tables 1 and 2 refers to comparative tests on 40 mm OD nylon pipes having a wall thickness of 1.21 - 1.33 mm. Prior art adhesives have a pressure at failure (kPa) of 1700-2000 on the comparative test.
• compositions of the invention are suitable for nylon pipe jointing, with the compositions of Table 2 being preferred.
• Adhesion to the nylon substrate is thought to be the result of a number of chemical reactions occurring concurrently. These reactions may include alkoxyalkylation of the nylon, cross linking between the resin and the substrate (chemical attachment of the adhesive to the substrate), and nylon formation in situ.
• the resin is less brittle than for example resorcinol formaldehyde resin. It is believed that the hexanone chain separates the benzene rings of the resorcinol units in the polymer chain reducing brittleness in comparison with, for example, a resorcinol formaldehyde resin.
• phenolic hydroxy group is a powerful electron repelling (and ortho para directing) group which tends to facilitate release of nuclear hydrogen atoms herein referred to as labile ring hydrogen permitting reaction with the ketone or aldehyde and that a substantially similar reaction can be conducted with substituted phenols such as the cresols or polyhydric phenols such as the 1,4 dihydric phenol and others in which a hydrogen is to an extent labile by virtue of the nuclear substituents.
• cyclohexanone is preferred and has the advantage that on fission of the ring there is formed a chain reactive at each end, a similar result can be achieved for example by use of a straight chain dialdehyde.
• the bridge for example a -(CH 2 ) n - bridge, between phenolic rings has at least 6 carbon atoms in order to obtain sufficient flexibility and other desired properties and therefore if a straight chain dialdehyde is used it should have at least 6 carbons including those to which the aldehyde oxygen is bonded.
• straight chain unsubstituted dialdehydes are preferred, those with alkyl or substituents may be used and preferably lower alkyl substituents.
• Resins according to the invention may find use as an adhesive for all nylon materials and components (especially for the more polar nylons such as nylon 11, 12, 610 or 612).
• Resorcinol formaldehyde (RF) resins are used in the manufacture of laminated wood structures and in the manufacture of plywood.
• the brittle nature of cured RF adhesives can lead to problems in service of these structures.
• Resins according to the invention and especially when mixed with paraformaldehyde may prove suitable as a substitute for RF adhesives.
• compositions according to the invention may be provided with fillers, pigment like additives without departing from the scope of the invention herein described.

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• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Engineering & Computer Science (AREA)
• Manufacturing & Machinery (AREA)
• Materials Engineering (AREA)
• Adhesives Or Adhesive Processes (AREA)
• Phenolic Resins Or Amino Resins (AREA)

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• 1983
  • 1983-04-27 DK DK188483A patent/DK165011C/da not_active IP Right Cessation
  • 1983-04-29 WO PCT/AU1983/000052 patent/WO1983003832A1/en unknown
  • 1983-04-29 NZ NZ204048A patent/NZ204048A/en unknown
  • 1983-04-29 ZA ZA833048A patent/ZA833048B/xx unknown
  • 1983-04-29 EP EP83901313A patent/EP0107684A1/en not_active Withdrawn

Non-Patent Citations (1)

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