WO1997027993A1 - Liquid composite moulding process - Google Patents
Liquid composite moulding process Download PDFInfo
- Publication number
- WO1997027993A1 WO1997027993A1 PCT/GB1997/000269 GB9700269W WO9727993A1 WO 1997027993 A1 WO1997027993 A1 WO 1997027993A1 GB 9700269 W GB9700269 W GB 9700269W WO 9727993 A1 WO9727993 A1 WO 9727993A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- mould
- resin
- titanate
- liquid
- titanates
- Prior art date
Links
Classifications
-
- 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
- C08K5/56—Organo-metallic compounds, i.e. organic compounds containing a metal-to-carbon bond
-
- 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
- B29C67/246—Moulding high reactive monomers or prepolymers, e.g. by reaction injection moulding [RIM], liquid injection moulding [LIM]
-
- 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
- B29C70/40—Shaping or impregnating by compression not applied
- B29C70/42—Shaping or impregnating by compression not applied for producing articles of definite length, i.e. discrete articles
- B29C70/46—Shaping or impregnating by compression not applied for producing articles of definite length, i.e. discrete articles using matched moulds, e.g. for deforming sheet moulding compounds [SMC] or prepregs
- B29C70/48—Shaping or impregnating by compression not applied for producing articles of definite length, i.e. discrete articles using matched moulds, e.g. for deforming sheet moulding compounds [SMC] or prepregs and impregnating the reinforcements in the closed mould, e.g. resin transfer moulding [RTM], e.g. by vacuum
Definitions
- This invention relates to a liquid composite moulding (LCM) process and more particularly to the use of organometallic coupling agents in LCM.
- LCM process is one in which a liquid resin (usually a thermosetting resin), or liquid reaction components for the resin, is injected into a mould and allowed to cure in the mould. Following curing, the resulting moulded article is removed from the mould.
- LCM comprises a number of techniques, such as:
- RTM resin transfer moulding
- VARI vacuum assisted resin injection
- R-RIM reinforced reaction injection moulding
- S-RIM structural reaction injection moulding
- RTM and S-RIM various types of additives are added to the resin and mixed, prior to the addition of powder type fillers.
- the resin mixture and any additional reactants (such as hardeners or accelerators) are then mixed and injected into a mould loaded with fibrous reinforcements. Once the resin is set, the mould is opened and the moulded article removed.
- vacuum is used instead of pressure to introduce the resin mixture into the mould.
- RTM and VARI can be combined together, whereby both pressure and vacuum are used concurrently to fill the mould.
- the reinforcements, if added are placed in one of the reactants with the lowest viscosity, and injected into an empty mould once the other reactants are mixed in.
- the resins used are any liquid mouldable resins.
- the fillers most commonly used are calcium carbonate or alumina trihydrate (ATH) powders.
- the reinforcement is usually mats made from continuous or discontinuous fibres, particularly glass fibres. Such techniques are used in a variety of applications worldwide, in a number of fields such as automotive, transport and industrial.
- Coupling agents are chemicals which have been known to promote adhesion between mostly (but not limited to) mineral or inorganic phases and organic phases, typically in mineral filled and or glass reinforced polymer systems. More contributions to the understanding of the required functionalities, thus possible chemical structures of the coupling agent can be found by exploring the most significant reaction processes which, for silane based coupling agents are:
- R must be a hydrolysable organic group (hence functional) and the R'-Si bond is preferably non-hydrolysable but stable throughout this reaction.
- Organometallic Coupling agents eg. Al, Ti, Zr, or Zr-Al based coupling agents: -
- the mechanisms are different where the organometallic coupling agent reacts with the substrate surface protons of the inorganic phase, resulting in the formation of matrix-compatible/reactive organic layers on the inorganic surface by one or more of the following reaction categories :- alcoholysis (solvolysis), surface chelation, co-ordination exchange, co-ordination salt formation, polymer ligand exchange catalysis and organic ligand interaction.
- reaction categories :- alcoholysis (solvolysis), surface chelation, co-ordination exchange, co-ordination salt formation, polymer ligand exchange catalysis and organic ligand interaction.
- IP Inorganic phase
- CA Coupling Agent
- n can be any number.
- Coupling agents can either be coated onto the inorganic phases or added to the organic phase prior to mixing any other constituents.
- the coupling agents can be organometallic compounds, in particular titanates, zirconates, aluminates and zircoaluminates.
- Organometallic coupling agents are also known to improve the rheological properties of composite materials during processing. For example, titanate-based coupling agents were found to reduce the mixing time of the constituents used in manufacturing Bulk Moulding Compounds (BMC), see Katz et al referred to above, Chapter 4. Titanates and zircoaluminates have also been reported to be more effective in reducing viscosity and flow activation energy when compared with silicon-based coupling agents (silanes) in unsaturated polyester, as described in the following references:
- a particular problem which we have identified in LCM processes is the fact that the reinforcement in the mould acts as a filter. This causes the dispersion of filler in the resin to become non-uniform, with deterioration of mechanical, fire, smoke and toxicity (FST) and electrical properties.
- Additives are currently used in LCM processes for filler dispersion and for wetting, e.g. air release agents which attempt to eliminate pockets of air in the reinforcements.
- An example of such additives is silicon-based compounds, e.g. polyester modified ethylalkylpolysiloxane copolymer which is available from BYK-Chemie GmbH, Germany.
- such additives do not satisfactorily solve the problem of filler filtration.
- NIM Network Injection Moulding
- SCRIMP Seemann Composite Resin Infusion Moulding Process
- a liquid composite moulding process in which a liquid mouldable resin, or reaction components therefor, is injected into a mould, allowed to cure in the mould, and the resulting moulded article removed from the mould, characterised in that an organometallic coupling agent is in contact with the liquid resin or reaction components during injection thereof into the mould.
- the invention also relates to the use of an organometallic coupling agent in liquid composite moulding for reducing filler filtration.
- organometallic coupling agents are used as a means of reducing filler filtration and as a flow modifier in LCM generally, and in particular in RTM, VARI, R-RIM and S-RIM. Furthermore, the organometallic coupling agents improve composite surface finish by reducing surface roughness and improve mechanical properties by reducing fibre mat deformation (fibre wash) which tends to occur during mould fill.
- the organometallic coupling agents represent a significant improvement over silicon- based additives. The use of the organometallic coupling agents leads to significantly improved LCM cycle time, product quality and process economics.
- the invention is preferably applicable to cases where fibrous reinforcements are present in the mould and are permeated by the liquid resin or reaction components.
- Suitable fibres include glass fibre, carbon fibre and aramid fibre.
- the invention permits a high volume fraction of fibre (e.g. up to 60%) and long fibres (e.g. 200 microns or greater) as well as continuous fibres to be used.
- the fibres used can be random, woven or unidirectional in a variety of styles. In the case of R-RIM, shorter fibrous reinforcements are used and these are dispersed in one of the reaction components.
- the resins which can be used include liquid mouldable resin, such as epoxy, polyesters, vinylesters, acrylics, poiyurethanes, polyureas and phenolics.
- liquid mouldable resin such as epoxy, polyesters, vinylesters, acrylics, poiyurethanes, polyureas and phenolics.
- the reaction components which together form the liquid thermosetting resin e.g. an epoxy resin and a curing agent
- the reaction components which together form the liquid thermosetting resin are mixed by impingement of separate streams, immediately before injection into the mould.
- the resins contain filler, in particular particulate fillers such as calcium carbonate, alumina trihydrate, talc, quartz, titanium oxide, carbon black or glass spheres.
- the organometallic coupling agent can be added to the liquid thermosetting resin or to one or more of the reaction components. It can also be used as a coating on the fibrous reinforcements and/or on filler particles. More than one coupling agent can be used simultaneously.
- the proportion of organometallic coupling agent which is present is generally up to 2.0 phf, preferably around 0.2-2.0 phf (parts per hundred of filler).
- organometallic coupling agents which can be used are known compounds, such as those disclosed in the Monte and Katz et al references mentioned above.
- Particularly preferred organometallic coupling agents are compounds of the following general types:
- Neoalkoxy titanates eg. LICA 38: neopentyl(diallyl)oxy, tri(dioctyl)pyro-phosphato titanate
- Chelate aluminates eg. KA301 : diisobutyl(oleyl)aceto acetyl aluminate.
- Quat titanates and Zirconates eg. KR238A/M: acrylate functional amine adduct of KR238S / methacrylate functional amine adduct of KR238S).
- Coordinate titanates and Zirconates eg. KR55: tetra (2,2 diallyoxymethyl)butyl, di(ditridecyl)phosphito titanate).
- Cycloheteroatom titanates and zirconates eg. KROPPR : cyclo(dioctyl)pyrophosphato dioctyl titanate.
- Neoalkoxy zirconates eg. NZ38: zirconium IV 2,2(bis-2-propenolatomethyl) butanolato , tri s(diocty l)pyrophosphato-0
- Chelate titanates eg. KR238S: di(dioctyl)pyrophosphato ethylene titanate.
- General formulae for some of the above types are given on page 78 of the Katz et al reference.
- Other suitable coupling agents are listed in the following:
- the invention thus relates to the addition of organometallic coupling agents, such as titanate, zirconates, aluminates and their combinations such as zircoaluminates, to filler-loaded liquid mouldable resins, e.g. thermosetting resins such as epoxy, polyester, acrylics, but not excluding others, used in LCM in order to reduce mould fill time, reduce filler filtration, reduce surface roughness, increase mechanical performance and reduce overall product cost.
- organometallic coupling agents such as titanate, zirconates, aluminates and their combinations such as zircoaluminates
- the effect of the invention is more based on the capability of the organometallic coupling agents to act as effective dispersing agents, reducing filler filtration by the reinforcements.
- the invention has the following advantages:
- filler filtration is substantially reduced relative to silicon-based additives for a given mould, set of operating conditions and materials. This results in improved product performance, such as higher mechanical and lower fire, smoke and toxicity (FST) values.
- FST fire, smoke and toxicity
- the invention is illustrated by the following Examples.
- the coupling agents used are described in the Monte reference identified above.
- KR238 A or M was mixed (0.5 phf) with unsaturated polyester resin (Norpol 4010) and two levels of CaCO3 (60 and 120 phr).
- the mixtures were moulded by RTM using Woven Roving (W/R) glass mat (566 g/m 2 ) and surface veil giving fibre volume content of 38% .
- W/R Woven Roving
- Two mould temperatures were used, 50 and 60°C, and 3.8 bar resin injection pressure.
- BYK-W995 (1.25 phf)
- a silicon-based additive instead of KR238 A or M.
- KR238 A was mixed (0.5 phf) with unsaturated polyester (Norpol 4010) and 60 phr CaCO3.
- the resin mixture was injected into a mould set at 50°C temperature and loaded with continuous filament mat (CFM) fibre reinforcement (450g/m 2 ) and surface veil giving a fibre content of 38%.
- the injection pressure was 3.8 bar.
- the same was repeated with 1.25 phf of BYK-W995 instead of KR238A.
- KR238S was mixed (1.25 phf) with modified acrylic resin (Modar 836S) and 60 phr of a mixture of FST filler powders (mainly alumina trihydrate).
- the resin mixture was moulded by RTM using a non crimp triaxial (0/+45/-45) glass fabric (Cotech ETLX- 1169-3131) of 1169 g/m 2 weight giving fibre volume content of 40% .
- Mould temperature was 40°C and the resin injection pressure was 4 bar. The same again was repeated with BYK-W995 (1.25 phf) instead of KR238S.
- organometallic coupling agents were individually mixed (1.25 phf) with polyester resin (Norpol 4010) and 50 phr CaCO3 filler powder.
- the resin mixtures were injected into a mould at 3.8 bar pressure, which contained W/R glass fibre reinforcement and surface veil (36% fibre volume).
- the mould temperature was set at 50°C.
- the same filler, reinforcement and moulding conditions were employed again using BYK-W995 (1.25 phf) instead of organometallic coupling agents.
- Example 4 As in Example 4 but using modified acrylic resin (Modar 836S) instead of polyester resin, 50 phr FST filler powders instead of 50 phr CaCO 3 and BYK- W996 instead of BYK-W995.
- Mod 836S modified acrylic resin
- organometallic coupling agents (given below) were individually mixed (1.25 phf) with epoxy resin (Bis-F) and 50phr CaCO3 filler powder.
- the resin mixtures were injected into a mould at 3.8 bar pressure which contained W/R glass fibre reinforcement and surface veil (36% fibre content).
- the mould temperature was set at 60°C.
- the same filler, reinforcement and moulding conditions were employed again using BYK-A530 (1.25 phf) and BYK-S732 (1.25phf) instead of organometallic coupling agents.
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- Chemical & Material Sciences (AREA)
- Mechanical Engineering (AREA)
- Engineering & Computer Science (AREA)
- Medicinal Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Composite Materials (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Injection Moulding Of Plastics Or The Like (AREA)
- Processes Of Treating Macromolecular Substances (AREA)
- Reinforced Plastic Materials (AREA)
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP9527418A JP2000503922A (en) | 1996-01-30 | 1997-01-30 | Liquid composite material molding method |
AU15533/97A AU1553397A (en) | 1996-01-30 | 1997-01-30 | Liquid composite moulding process |
GB9814948A GB2324063A (en) | 1996-01-30 | 1997-01-30 | Liquid composite moulding process |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GBGB9601783.5A GB9601783D0 (en) | 1996-01-30 | 1996-01-30 | Liquid composite moulding process |
GB9601783.5 | 1996-01-30 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1997027993A1 true WO1997027993A1 (en) | 1997-08-07 |
Family
ID=10787755
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/GB1997/000269 WO1997027993A1 (en) | 1996-01-30 | 1997-01-30 | Liquid composite moulding process |
Country Status (4)
Country | Link |
---|---|
JP (1) | JP2000503922A (en) |
AU (1) | AU1553397A (en) |
GB (1) | GB9601783D0 (en) |
WO (1) | WO1997027993A1 (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7390579B2 (en) * | 2003-11-25 | 2008-06-24 | Magnequench, Inc. | Coating formulation and application of organic passivation layer onto iron-based rare earth powders |
FR2953755B1 (en) * | 2009-12-14 | 2012-01-20 | Rhodia Operations | PROCESS FOR MANUFACTURING COMPOSITE ARTICLES BASED ON POLYAMIDE |
Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4069192A (en) * | 1976-01-30 | 1978-01-17 | Kenrich Petrochemicals, Inc. | Liquid thermosetting resins containing titanate salts |
US4269756A (en) * | 1979-12-27 | 1981-05-26 | Union Carbide Corporation | Use of organotitanate in the encapsulation of electrical components |
GB2147592A (en) * | 1983-10-06 | 1985-05-15 | Basf Wyandotte Corp | Reducing the viscosity of filled liquid polymers |
WO1985005069A1 (en) * | 1984-05-09 | 1985-11-21 | Hughes Aircraft Company | Method of fabricating composite or encapsulated articles |
EP0164227A2 (en) * | 1984-05-14 | 1985-12-11 | Kenrich Petrochemicals, Inc. | Neoalkoxy organo-titanates and organo-zirconates useful as coupling and polymer processing agents |
US4681718A (en) * | 1984-05-09 | 1987-07-21 | Hughes Aircraft Company | Method of fabricating composite or encapsulated articles |
JPS63270108A (en) * | 1987-04-29 | 1988-11-08 | Toyoda Gosei Co Ltd | Reaction injection molded product of insert |
JPS63270107A (en) * | 1987-04-29 | 1988-11-08 | Toyoda Gosei Co Ltd | Reaction injection molded product of insert |
US5045575A (en) * | 1989-12-18 | 1991-09-03 | General Dynamics Corporation, Convair Division | Method of reducing voids in thermoset resin products |
JPH03231819A (en) * | 1990-02-07 | 1991-10-15 | Mazda Motor Corp | Reaction injection molding method |
JPH05104558A (en) * | 1991-10-16 | 1993-04-27 | Mazda Motor Corp | Material for reactive injection molding |
WO1994026505A1 (en) * | 1993-05-14 | 1994-11-24 | Imperial Chemical Industries Plc | Reinforced moulded articles and method of producing same |
EP0673957A2 (en) * | 1994-03-04 | 1995-09-27 | Mitsubishi Denki Kabushiki Kaisha | Epoxy resin moulding composition |
-
1996
- 1996-01-30 GB GBGB9601783.5A patent/GB9601783D0/en active Pending
-
1997
- 1997-01-30 AU AU15533/97A patent/AU1553397A/en not_active Abandoned
- 1997-01-30 WO PCT/GB1997/000269 patent/WO1997027993A1/en active Application Filing
- 1997-01-30 JP JP9527418A patent/JP2000503922A/en active Pending
Patent Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4069192A (en) * | 1976-01-30 | 1978-01-17 | Kenrich Petrochemicals, Inc. | Liquid thermosetting resins containing titanate salts |
US4269756A (en) * | 1979-12-27 | 1981-05-26 | Union Carbide Corporation | Use of organotitanate in the encapsulation of electrical components |
GB2147592A (en) * | 1983-10-06 | 1985-05-15 | Basf Wyandotte Corp | Reducing the viscosity of filled liquid polymers |
WO1985005069A1 (en) * | 1984-05-09 | 1985-11-21 | Hughes Aircraft Company | Method of fabricating composite or encapsulated articles |
US4681718A (en) * | 1984-05-09 | 1987-07-21 | Hughes Aircraft Company | Method of fabricating composite or encapsulated articles |
EP0164227A2 (en) * | 1984-05-14 | 1985-12-11 | Kenrich Petrochemicals, Inc. | Neoalkoxy organo-titanates and organo-zirconates useful as coupling and polymer processing agents |
JPS63270108A (en) * | 1987-04-29 | 1988-11-08 | Toyoda Gosei Co Ltd | Reaction injection molded product of insert |
JPS63270107A (en) * | 1987-04-29 | 1988-11-08 | Toyoda Gosei Co Ltd | Reaction injection molded product of insert |
US5045575A (en) * | 1989-12-18 | 1991-09-03 | General Dynamics Corporation, Convair Division | Method of reducing voids in thermoset resin products |
JPH03231819A (en) * | 1990-02-07 | 1991-10-15 | Mazda Motor Corp | Reaction injection molding method |
JPH05104558A (en) * | 1991-10-16 | 1993-04-27 | Mazda Motor Corp | Material for reactive injection molding |
WO1994026505A1 (en) * | 1993-05-14 | 1994-11-24 | Imperial Chemical Industries Plc | Reinforced moulded articles and method of producing same |
EP0673957A2 (en) * | 1994-03-04 | 1995-09-27 | Mitsubishi Denki Kabushiki Kaisha | Epoxy resin moulding composition |
Non-Patent Citations (3)
Title |
---|
DATABASE WPI Week 9321, Derwent World Patents Index; AN 93-172212, XP002030612 * |
PATENT ABSTRACTS OF JAPAN vol. 013, no. 067 (M - 798) 15 February 1989 (1989-02-15) * |
PATENT ABSTRACTS OF JAPAN vol. 016, no. 010 (M - 1199) 13 January 1992 (1992-01-13) * |
Also Published As
Publication number | Publication date |
---|---|
JP2000503922A (en) | 2000-04-04 |
AU1553397A (en) | 1997-08-22 |
GB9601783D0 (en) | 1996-04-03 |
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