GB2102331A - Anisotropic resins - Google Patents
Anisotropic resins Download PDFInfo
- Publication number
- GB2102331A GB2102331A GB08219965A GB8219965A GB2102331A GB 2102331 A GB2102331 A GB 2102331A GB 08219965 A GB08219965 A GB 08219965A GB 8219965 A GB8219965 A GB 8219965A GB 2102331 A GB2102331 A GB 2102331A
- Authority
- GB
- United Kingdom
- Prior art keywords
- resin
- anisotropic
- properties
- different
- epoxy resin
- 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.)
- Granted
Links
- 239000011347 resin Substances 0.000 title claims abstract description 27
- 229920005989 resin Polymers 0.000 title claims abstract description 27
- 239000000203 mixture Substances 0.000 claims abstract description 26
- 239000003822 epoxy resin Substances 0.000 claims abstract description 17
- 229920000647 polyepoxide Polymers 0.000 claims abstract description 17
- 239000007822 coupling agent Substances 0.000 claims description 19
- 238000000034 method Methods 0.000 claims description 11
- LNEPOXFFQSENCJ-UHFFFAOYSA-N haloperidol Chemical compound C1CC(O)(C=2C=CC(Cl)=CC=2)CCN1CCCC(=O)C1=CC=C(F)C=C1 LNEPOXFFQSENCJ-UHFFFAOYSA-N 0.000 claims description 4
- 238000011065 in-situ storage Methods 0.000 claims description 3
- 239000000126 substance Substances 0.000 claims description 3
- 230000007704 transition Effects 0.000 claims description 2
- 239000003795 chemical substances by application Substances 0.000 abstract 2
- IISBACLAFKSPIT-UHFFFAOYSA-N bisphenol A Chemical compound C=1C=C(O)C=CC=1C(C)(C)C1=CC=C(O)C=C1 IISBACLAFKSPIT-UHFFFAOYSA-N 0.000 description 5
- 230000008569 process Effects 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- 230000008859 change Effects 0.000 description 3
- 238000001125 extrusion Methods 0.000 description 3
- 229920000642 polymer Polymers 0.000 description 3
- 229930185605 Bisphenol Natural products 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000009833 condensation Methods 0.000 description 2
- 230000005494 condensation Effects 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 239000010410 layer Substances 0.000 description 2
- 239000000178 monomer Substances 0.000 description 2
- 229920001021 polysulfide Polymers 0.000 description 2
- 239000005077 polysulfide Substances 0.000 description 2
- 150000008117 polysulfides Polymers 0.000 description 2
- 239000011541 reaction mixture Substances 0.000 description 2
- 230000002787 reinforcement Effects 0.000 description 2
- 239000002344 surface layer Substances 0.000 description 2
- 239000002562 thickening agent Substances 0.000 description 2
- 239000013008 thixotropic agent Substances 0.000 description 2
- 238000004804 winding Methods 0.000 description 2
- 125000001931 aliphatic group Chemical group 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000004132 cross linking Methods 0.000 description 1
- GYZLOYUZLJXAJU-UHFFFAOYSA-N diglycidyl ether Chemical compound C1OC1COCC1CO1 GYZLOYUZLJXAJU-UHFFFAOYSA-N 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000003365 glass fiber Substances 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 229920000768 polyamine Polymers 0.000 description 1
- 239000004848 polyfunctional curative Substances 0.000 description 1
- 125000002924 primary amino group Chemical class [H]N([H])* 0.000 description 1
- 239000012779 reinforcing material Substances 0.000 description 1
- 239000011342 resin composition Substances 0.000 description 1
- 230000007480 spreading Effects 0.000 description 1
- 239000000057 synthetic resin Substances 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
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
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C31/00—Handling, e.g. feeding of the material to be shaped, storage of plastics material before moulding; Automation, i.e. automated handling lines in plastics processing plants, e.g. using manipulators or robots
- B29C31/04—Feeding of the material to be moulded, e.g. into a mould cavity
- B29C31/06—Feeding of the material to be moulded, e.g. into a mould cavity in measured doses, e.g. by weighting
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C67/00—Shaping techniques not covered by groups B29C39/00 - B29C65/00, B29C70/00 or B29C73/00
- B29C67/24—Shaping techniques not covered by groups B29C39/00 - B29C65/00, B29C70/00 or B29C73/00 characterised by the choice of material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
- B29C70/003—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts characterised by the matrix material, e.g. material composition or physical properties
- B29C70/0035—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts characterised by the matrix material, e.g. material composition or physical properties comprising two or more matrix materials
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
- B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
- B29C70/28—Shaping operations therefor
- B29C70/30—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core
- B29C70/36—Shaping by lay-up, i.e. applying fibres, tape or broadsheet on a mould, former or core; Shaping by spray-up, i.e. spraying of fibres on a mould, former or core and impregnating by casting, e.g. vacuum casting
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
- B29B15/00—Pretreatment of the material to be shaped, not covered by groups B29B7/00 - B29B13/00
- B29B15/08—Pretreatment of the material to be shaped, not covered by groups B29B7/00 - B29B13/00 of reinforcements or fillers
- B29B15/10—Coating or impregnating independently of the moulding or shaping step
- B29B15/12—Coating or impregnating independently of the moulding or shaping step of reinforcements of indefinite length
- B29B15/122—Coating or impregnating independently of the moulding or shaping step of reinforcements of indefinite length with a matrix in liquid form, e.g. as melt, solution or latex
- B29B15/127—Coating or impregnating independently of the moulding or shaping step of reinforcements of indefinite length with a matrix in liquid form, e.g. as melt, solution or latex by spraying
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2033/00—Use of polymers of unsaturated acids or derivatives thereof as moulding material
- B29K2033/04—Polymers of esters
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2063/00—Use of EP, i.e. epoxy resins or derivatives thereof, as moulding material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2067/00—Use of polyesters or derivatives thereof, as moulding material
- B29K2067/06—Unsaturated polyesters
-
- 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
- C08J2363/00—Characterised by the use of epoxy resins; Derivatives of epoxy resins
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Mathematical Physics (AREA)
- Composite Materials (AREA)
- Robotics (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Moulding By Coating Moulds (AREA)
Abstract
Epoxy resin structures having anisotropic properties en masse are produced by varying the composition of the resin mix, e.g. by varying the proportions of two or more epoxy resin components and/or curing agents in the mix, or simply by varying the relative proportions of epoxy resin and curing agent, in different regions of the structure.
Description
SPECIFICATION
Anisotropic resins
This invention relates to anisotropic resins.
Polymers are known which have anisotropic properties at least at the molecular level, for example, elastomeric block polymers of the ABA and other similar types. However, the anisotropy does not extend to the polymer en masse.
The present invention, on the other hand, contemplates synthetic resin structures, specifically epoxy resin structures, having anisotropic properties en masse. In accordance with this invention these are produced by in situ condensation of the resin eitherlnterse in the presence of a catalyst or in the presence of a coreactive hardener or coupling agent to produce a polymerised structure, wherein, in different regions of the structure, the composition and/or proportions of the resin and/or the coupling agent are varied thereby to give rise to a polymeric structure having anisotropic properties en masse.
Preferably, there will be a gradual change of compositions and/or proportions of the mix from one region of the structure to the next, thereby to provide a gradual, rather than an abrupt charge in the physical or other properties of the structure.
This will be of advantage in eliminating internal stress and strain characteristics within the final structure resulting from discontinuities in the resin composition. In this connection, it will be understood that the term 'anisotropy' is being used in a broad sense to include any change of properties, whether physical or chemical, from one region of the resin to the other.
The concept of the invention can theoretically be applied to any moulding process, continuous or otherwise, involving the in situ condensation or curing of epoxy resin, with or without a coupling agent, wherein it is possible during the process or in different regions of the mould, to vary the composition and/or proportions of the reaction mix. For example, in an extrusion moulding process involving the extrusion of a reaction mix through a nozzle with concomitant or subsequent curing of the mix in the extrudate, the proportion or composition of the components of the mix fed to the nozzle can be varied as the extrusion proceeds so that the properties of the extrudate vary along its length.
Without in any way restricting the scope of the present invention, the following illustration of its application is given. For example, in a conventional epoxy resin system comprising as the resin component the bis-glycidyl ether of bisphenol A or bis-phenol F and, as the coupling agent, a polyfunctional primary amine or a polysulfide, the chemical and/or physical properties of the cured resin can be varied in different regions of the structure by any of the following techniques::
1. variation in the epoxy resin component, for example, by replacing part of the bis-phenol A or bis-phenol F component of the resin by a compatible aliphatic diepoxy compound;
2. variation in the coupling agent, for example, by replacing all or part of a short chain polyamine or polysulfide, with a longer chain compound;
3. variation in the relative proportions of the epoxy resin and the coupling agent, thereby to produce different degrees of cross-linking in different regions of the cured product.
Two methods of carrying out the present invention are further described with reference to and illustrated by the accompanying drawings, in which
Fig. 1 is a diagrammatic lay out of a mould and injection nozzle system for use in accordance with this invention; and
Fig. 2 is a diagrammatic view of a technique for winding a flexible drive shaft in accordance with this invention.
Referring to Fig. 1, a mould 1 defines a shallow longitudinally extending mould cavity 2 of a desired shape. Mounted above the mould is a mixing nozzle 3 which is movable, by means not shown, along the length of the mould in the direction of the arrow A and back again. A plurality of feed lines X, Y and Z are connected to the nozzle for individually feeding thereto a combination of, for example, two different but compatible epoxy resins and one coupling agent, or one epoxy resin and two different coupling agents, the flow of each component being controllable by suitable control means, not shown.
At the beginning of the casting operation, a reinforcement material 4, e.g. glass or carbon fibre, is laid in the mould cavity. The mould cavity is then filled with the resin mix by moving the nozzle along the length of the mould and discharging the resin components, X, Y and Z, which in accordance with the principles of this invention will vary in proportion along the length of the mould to produce a structure having anisotropic properties en masse.In a particular strucutre envisaged in accordance with this invention, at one or both ends the monomer mix will contain a high proportion of a short chain polyfunctional coupling agent to produce a highly cross-linked, rigid structure at one or both ends, suitable for the subsequent mounting or attachment of those ends to a supporting structure, whilst the central region contains a lower proportion of the coupling agent, or a longer chain coupling agent, thereby to produce a central region of greater flexibility and or toughness.
Instead of varying the resin mix at the end or ends of the structure, in an alternative enbodiment, a layered structure can be built up by several passes of the nozzle and varying the resin mix in one or more passes thereby to provide, for example, a structure having a flexible or toughened central core or layer and a rigid or hard surface layer or layers.
As already indicated, a gradual transition is desirable in the composition of the resin mix from one region to the next, rather than an abrupt change, and with highly fluid components it may be necessary to incorporate thickeners or thixotropic agents to reduce flow of resin or coupling agent from one region to the next.
Following the charging of the mould, polymerisation can be initiated to complete the polymerisation process.
Referring to Fig. 2, this diagrammatically represents the winding of a web 10, e.g. of carbon or glass fibre, on to a rotating mandrel 1 to form a helically wound shaft 12 of resin impregnated reinforcement. As the web is wound onto the shaft it is impregnated with a resin mix applied through a mixing nozzle 13 and supplied through lines P, Q and R with the individual components of the mix e.g. the combination of two different but compatible epoxy resins and one coupling agent, or one resin with two differerit coupling agents the proportions of which are varied depending on the part of the shaft being wound, for example, the ends or the middle section, or alternatively the inner or the outer layers.
As will be appreciated many variations may be made to the above techniques without departing from the scope of the invention as claimed.
As already indicated, in certain cases it may be desirable to incorporate thickeners or thixotropic agents in the monomer mix in order to prevent undue spreading of components from one region of the structure to the next.
As well as variations within the resin mix itself to give the desired anisotropic properties to the polymeric structure, the anisotropic characteristics can be increased or modified by incorporating reinforcing materials such as glass or carbon fibre into the structure.
It is envisaged that anisotropic resin structures in accordance with the invention can be utilised in a wide variety of ways where anisotropic properties are required. For example, it is envisaged that car body panels can be fabricated having areas of high rigidity and other areas of high flexibility; dinghy masts can be constructed having a rigid foot but with closely controlled bending and torsional characteristics along its length; helicopter rotor blades can be fabricated having the desired flexibility, but yet providing a rigid load bearing end for connection to the rotor hub; vehicle transmission shafts can be constructed having rigid load bearing ends for connection to the drive and separated by a central, flexible section; and so on.
Claims (5)
1. A method of producing an epoxy resin structure which comprises curing an epoxy resin or resin mixture in situ, either catalytically or in the presence of a coupling agent to form said structure, wherein the composition and/or proportions of the resin mix used to form said structure are varied in different regions thereof, thereby to produce a cured epoxy resin structure having anisotropic characteristics en masse.
2. A method according to claim 1, wherein said resin mix comprises two or more epoxy resins capable of providing different polymeric characteristics and/or two or more coupling agents capable of providing different properties in the cured product, and wherein the proportion of said two or more resins and/or the proportions of said two or more coupling agents are varied in said different regions of the structure, thereby to produce said anisotropic properties in the cured structure.
3. A method according to claim 1 or 2, wherein the composition and/or proportions of the resin mix is gradually varied from one region of the structure to the next, thereby to provide a gradual transition of physical and/or chemical properties in the structure.
4. A cured epoxy resin structure having anisotropic properties en masse.
5. A structure according to claim 4, wherein the anisotropic properties result from the use of different epoxy resins, or different coupling agents or different properties of resin and coupling agent, in different regions of the structure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB08219965A GB2102331B (en) | 1981-07-09 | 1982-07-09 | Anisotropic resins |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8121249 | 1981-07-09 | ||
| GB08219965A GB2102331B (en) | 1981-07-09 | 1982-07-09 | Anisotropic resins |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2102331A true GB2102331A (en) | 1983-02-02 |
| GB2102331B GB2102331B (en) | 1985-03-27 |
Family
ID=26280076
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08219965A Expired GB2102331B (en) | 1981-07-09 | 1982-07-09 | Anisotropic resins |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2102331B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002038354A1 (en) * | 2000-11-09 | 2002-05-16 | Pur Elastomer Aps | Polymer product with continuously graduated hardness |
| EP2055461A1 (en) * | 2007-10-30 | 2009-05-06 | Murata Machinery, Ltd. | Method and apparatus for impregnating fibres during fibre winding molding |
-
1982
- 1982-07-09 GB GB08219965A patent/GB2102331B/en not_active Expired
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002038354A1 (en) * | 2000-11-09 | 2002-05-16 | Pur Elastomer Aps | Polymer product with continuously graduated hardness |
| EP2055461A1 (en) * | 2007-10-30 | 2009-05-06 | Murata Machinery, Ltd. | Method and apparatus for impregnating fibres during fibre winding molding |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2102331B (en) | 1985-03-27 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |