Insulation material

Abstract

An insulation material to be applied to a substrate, for example a wall or ceiling, comprises particles, for example comminuted wool fibres, in a polymeric binder. Voids may be present within the insulation material, improving the thermal resistance and reducing weight and cost. Voids may form naturally, for example as a consequence of a degree of incompatibility between the particles and the binder, or by intervention, for example following plasma treatment.

Description

[0001] Insulation material

[0002] The present invention relates to a form of insulation that may be applied to internal walls o f a building or structure .

[0003] Appropriate thermal insulation of buildings is important to retain heat and thereby reduce energy costs . The use of insulation materials can be helpful in reducing carbon emissions and their negative impact on the environment .

[0004] Typical thermal insulation materials for buildings include natural and synthetic fibres , and also foams which are often used in roofs , walls and floors .

[0005] Ideally, insulation is installed during the construction of the building, so that it can be easily applied and then hidden once installed . However, older, poorly insulated buildings also require insulation to be retrofitted, for example by applying an insulation layer over the walls of a room . A common problem with this , when applying to the internal surfaces of the walls , is the ensuing reduction in room si ze that retrofitting insulation causes . Layers of insulation materials must be installed which are then typically covered in plaster board / drywall and then skimmed over with a thin layer of plaster before a decorative finish is applied . Not only does the extra wall thickness introduced reduce the volume of the room, but certain types of fixtures and fittings , such as radiators and electrical sockets for example , must be moved and refitted after the installation, increasing the total cost and time scale of the proj ect . A further problem is that when applying insulation around windows , the amount of light that enters a room may be reduced . In the case of many older buildings whose walls are constructed without a cavity, and which are designed for water vapour to pass through, the retro-applied installation of vapour-closed insulation materials prevents walls functioning as designed, with the consequent risk over time of moisture build-up within the walls which can cause rot , mould, condensation and reduce the thermal performance of the wall . Even where buildings do have cavities , these may be compromised by ingress of waste and so , may not be suitable to receive insulation within, for risk of causing cold spots .

[0006] Aerogels are known in the art for being good insulators . Aerogels are a highly porous , ultra-light synthetic material made from gels by replacing the solvents in the gel with air . This material has very low density and low thermal conductivity due to its mesopores typically being 50 nm or less . This structure also resists heat trans fer through conduction, convection and radiation . However, because the aerogels have low mechanical resistance and are brittle , they are di f ficult to work with and to apply to building surfaces including walls , floors and ceilings .

[0007] A poorly applied layer of aerogel , or any type of insulation, can lead to so-called cold bridges , or thermal bridges , which allow the transmission of heat and build-up of moisture leading to poor energy performance .

[0008] When applying insulation wet , water and surfactants can be added to an aerogel insulation mixture to make it more workable . However, i f the water content in the insulation mixture is too great initially, cracking of the insulation can also occur as it dries , due to the typically hygroscopic nature of the aerogel .

[0009] Embodiments of the present invention aim to provide an insulation material wherein the aforementioned i ssues are addressed .

[0010] The present invention is defined in the attached independent claims , to which reference should now be made . Further, preferred features may be found in the sub-claims appended thereto .

[0011] According to one aspect of the present invention there is provided an insulation material to be applied to a substrate , the material comprising particles and a polymeric binder .

[0012] The polymeric binder may be a polymer emulsion .

[0013] The polymeric binder may comprise a bio-derived polymer . Alternatively, or in addition, the polymeric binder may comprise a synthetic polymer or resin .

[0014] Where the polymeric binder is bio-derived, the binder may be at least one of a bio-derived acrylic, a bio-derived styrene- acrylic, a bio-derived polyurethane , a bio-derived poly (vinyl acetate-co-ethylene-co-vinyl-ester ) , a bioderived poly ( ethylene-co-vinyl ester-co-acrylic acid) , and / or a bio-derived poly (vinyl chloride-co-ethylene-co- vinyl ester ) . The sources of the bio-derived polymeric binder may be at least one of corn, soybean, brewer' s yeast , algae , whey, sugar cane , and potatoes . Where the polymeric binder is synthetic, the binder may be at least one of an acrylic, a styrene-acrylic, a polyurethane , a poly (vinyl acetate-co-ethylene-co-vinyl ) , a poly ( ethylene-co-vinyl ester-co-acrylic acid) , and / or a poly (vinyl chloride-co-ethylene-co-vinyl ester )

[0015] Where the binder is an emulsion, the emulsion may be a waterbased polymer . More preferably, the emulsion is a polymer- in-water emulsion .

[0016] Suitably the polymeric binder is an emulsion comprising 20- 80 parts by weight of polymer, to 80-20 parts by weight of water . Preferably it comprises 30-70 parts by weight of polymer, to 70-30 parts by weight of water . More preferably it comprises 40- 60 parts by weight of polymer, to 60-40 parts by weight of water .

[0017] Preferably, the polymer binder does not require a curing agent to set .

[0018] Preferably the insulation material comprises between 65- 95% wt / wt of polymer binder . More preferably, the insulation material comprises between 77- 90% wt / wt of polymer binder . Even more preferably, the insulation material comprises 83- 87 % wt / wt of polymer binder . A polymer binder comprises a polymer and may comprise a carrier , for example water . When it does include a carrier, the figures given refer to the weight of the polymer and the carrier, in combination .

[0019] Particles used in the invention may be derived from animal sources ; or from plant sources ; or from inanimate sources ( including natural sources , for example rocks and minerals , or synthetic sources , for example synthetic polymeric materials (including synthetically-modified natural materials) .

[0020] Particles from animal sources may be obtained from animal fleeces, and from shells. Examples include wool, chitin and chitosan .

[0021] Particles from plant sources may include particles of wood, bark, bamboo, cellulose, hemicellulose, cotton, sisal, flax, hemp and jute.

[0022] Particles from inanimate sources may include particles from mineral, ceramic and glass sources. Examples include clay silica, calcium carbonate, talc, sand, titanium dioxide and barium sulphate. Particles from inanimate sources may include particles which comprise at least one of polyamide, polyester, and / or polyacrylonitrile.

[0023] In preferred embodiments of the invention, the particles may comprise fibres. Thus they may be elongate in shape.

[0024] Fibres used in embodiments of this invention may be natural fibres .

[0025] Natural fibres useful in this invention may for example be selected from at least one of cellulose, cotton, hemicellulose, coir, jute, hemp, bamboo, flax, chitosan, chitin and wool. Mixtures of natural fibres may be used.

[0026] Some particles may not be elongate and so are not regarded in this specification as fibres. For example they may have been milled and may not have a pronounced aspect ratio. Such particles are sometimes called 'spherical particles' , though of course this is a convenient rather than a literal description. Any of the materials mentioned above as particles may be prepared as particles which are not fibres. Even a material which is naturally a fibre can be ground to the point where they no longer has fibre morphology.

[0027] Particles - fibres and non-fibre particles - used in the present invention suitably have the macroscopic form of a dust or powder. They may be formed by comminuting a larger starting material; for example by milling, chopping, pulverizing or grinding, or the like.

[0028] Particles used in embodiments of this invention may comprise a blend of natural and synthetic fibres.

[0029] Embodiments of the invention may employ a mixture of fibres and of non-fibre particles.

[0030] Preferred embodiments of the invention employ fibres. Wool fibres have been found to be particularly effective.

[0031] Suitably, the insulation material comprises 1-40% wt / wt of particles, for example 2-30% wt / wt of particles. More preferably, the insulation material comprises 5-18% wt / wt of particles. Even more preferably, the insulation material comprises 10-14% wt / wt of particles.

[0032] Preferably, the insulation material comprises 2-30% wt / wt of fibres. More preferably, the insulation material comprises 5-18% wt / wt of fibres. Even more preferably, the insulation material comprises 10-14% wt / wt of fibres. Preferably the particles used can pass through a sieve of mesh number 18 . This equates to a nominal opening of 1 mm . Preferably the particles can pass through a sieve of mesh number 35 . This equates to a nominal opening of 500 pm . More preferably the particles can pass through a sieve of mesh number 60 . This equates to a nominal opening of 250 pm .

[0033] Preferably the particles used can pass through a sieve of mesh number 80 . This equates to a nominal sieve opening of 180 pm . Suitably the particles can pass through a sieve of mesh number 120 . This equates to a nominal opening of 125 pm . Preferably the particles can pass through a sieve of mesh number 170 . This equates to a nominal opening of 90 pm . More preferably the particles can pass through a sieve of mesh number 325 . This equates to a nominal opening of 45 pm .

[0034] Suitably, however, the particles can substantially not pass through a sieve of mesh number 635 . This equates to a nominal opening of 20 pm . In reality a proportion of the particles may pass through a mesh 635 sieve because the particles will have a distribution of si zes and there will inevitably be some very small particles present . However the body of particles as a whole will not pass through the sieve .

[0035] Similarly, whilst the bulk of particles can pass through the sieves with large mesh si zes mentioned above there a likely to be outliers which cannot pass through .

[0036] The definitions given in this speci fication of mesh number refer to determination using a tap sieve shaker RO-TAP RX- 29 manufactured by W . S . Tyler of Ohio , USA. This model of sieve shaker has a dual motion action, namely circular motion in the hori zontal plane ( 278 oscillations per minute ) and vertical motion caused by mechanical 'tapping' onto the assembly of sieves, from an overhead tapping arm (150 taps per minute) . The dual motion makes it suitable to measure a wide range of particle shapes, including those having irregular or elongate shape. The sieves used are as designated in ASTM Ell. Protocols. Specifically, they are full depth sieves, 200 mm in diameter, manufactured in accordance with ASTM Ell and available from Endecotts Ltd, of Hope Valley, UK (https : / / www. endecotts . com)

[0037] For information on mesh sizes under the ASTM Ell protocol the reader may consult many available public information sources including https : / / www. endecotts . com / faq / sieves-and- calibrat ion / amer lean- standard-test-sieve-series-astm /

[0038] Preferably, the mean length of the fibres is in the range from 40 gm to 1 mm in length. More preferably, the mean length of the fibres is in the range from 50 gm to 500 gm in length. Even more preferably, the mean length of the fibres is in the range from 60 gm to 250 gm in length. Mean length can be determined, for example, by optical microscopy.

[0039] The insulation material may comprise a thickener. A physical thickener may be employed, for example a clay or gum, and / or a chemical thickener, for example an associative thickener, or an acrylic copolymer, for example a pre-neutralised dispersion of a water based acrylic copolymer.

[0040] Preferably, the insulation material comprises between 0-10% wt / wt of thickener. More preferably, the insulation material comprises 0-6% wt / wt of thickener. Even more preferably the insulation material comprises 0-6% wt / wt of thickener. The insulation material may further comprise a thixotropic agent . The thixotropic agent may comprise at least one of fumed silica, and clay . Where the thixotropic agent is a clay, the clay may comprise a mixture of silica and / or alumina with magnesium and water .

[0041] Preferably, the insulation material comprises between 0- 10% wt / wt of thixotropic agent . More preferably, the insulation material comprises 0- 8 % wt / wt of thixotropic agent . Even more preferably the insulation material comprises 0-5% wt / wt of thixotropic agent .

[0042] Alternatively, or in addition, the insulation material may comprise a pH regulator . The pH regulator may be at least one of citric acid, phosphoric acid, and / or mal ic acid . However, some favoured embodiments do not require a pH regulator .

[0043] Alternatively, or in addition, the insulation material may comprise hydrophobic agent . The hydrophobic agent may comprise a polysiloxane . The polysiloxane may be poly ( dimethyl-siloxane ) .

[0044] Preferably, the insulation material comprises between 0-20% wt / wt of total pH regulator, a thickening agent , hydrophobic agent , mineral filler, defoamer, antimicrobial additive , and fire retardant . More preferably, the insulation material comprises 0- 10% wt / wt of total pH regulator, hydrophobic agent , mineral filler, defoamer, antimicrobial additive , and fire retardant . Even more preferably, the insulation material comprises 0-5% of total pH regulator, hydrophobic agent , mineral filler, defoamer, antimicrobial additive , and fire retardant . A mineral filler may be a suitable clay . An antimicrobial additive may be present to inhibit bacterial growth within the binder material prior to use , for example in storage . An antimicrobial additive may be present to inhibit bacterial growth in the material post-application . Preferably both these types of antimicrobial additive are present .

[0045] The additional materials described above may themselves comprise particles which remain in the insulation material . Preferably, however, they are not the only particles present in the insulating material but , when present at all , may serve as a contributor to the complement of particles as defined above .

[0046] The insulation material may be non-metallic .

[0047] Preferably there are voids within the insulation material . The voids serve to reduce the thermal conductivity through the insulation material , and reduce the density, and potentially the cost .

[0048] In embodiments of the invention there may be a degree of repulsion or incompatibility between the polymeric binder and the particles . Thus , the adhesive forces between the particles and the binder are reduced . As a consequence voids may form naturally within the insulation material , as it sets . There can be many reasons why materials , for example a polymeric binder and particles therein, repel each other . In general , reasons for such repulsion may include one or more of electrostatic repulsion, steric repulsion, Van der Waals repulsion and electrosteric repulsion . In some embodiments the interfacial attraction between the particles and the polymer binder may be modi fied . In this way voids can be formed which otherwise would not be present ; or the morphology of voids may be changed; of the total volume of voids per given volume o f binder may be increased .

[0049] One way in which the interfacial attraction between the particles and the polymer binder may be modi fied may be achieved by subj ecting the particles to plasma treatment . The plasma treatment may comprise coating the surface of the particles with a perfluorocarbon . The perfluorocarbon may comprise hexafluoroethane . Alternatively, or in addition, the particles may be treated with a lubricant . The lubricant may comprise a perfluorocarbon . The perfluorocarbon may comprise hexafluoroethane . The voids may be microvoids commensurate in si ze with the particles .

[0050] In embodiments of the invention voids may constitute from 1 to 30 % vol / vol , of the insulation material , when set ; preferably from 2 to 20 % vol / vol , and preferably from 3 to 10 % vol / vol .

[0051] In other embodiments , the adhesive forces between the particles and the binder may be increased to increase the strength of the resulting insulation material . This may be achieved by the particles undergoing plasma treatment . The plasma treatment may comprise the use of oxygen and / or argon to etch the surface of the particles .

[0052] The insulation material may be a Thin Wall Insulation ( TIWI ) type . According to a further aspect of the present invention, there is provided an insulation material which is a solidi fied form of the insulation material of the first aspect of the invention, as defined above .

[0053] According to a further aspect of the present invention, there is provided a kit comprising particles and a polymeric binder that produces an insulation material when delivered in combination to a substrate . Preferably, the substrate is a wall and / or ceiling . More preferably, the substrate is an internal wall and / or ceiling .

[0054] According to another aspect of the present invention, there is provided a method of applying an insulation material to a substrate , the insulation material comprising particles and a polymer binder, the method comprising a step of combining particles with a polymer binder to produce the insulation material .

[0055] Where the insulation material comprises additives such as a thixotropic agent , pH regulator, hydrophobic agent , mineral filler, thickener, defoamer, antimicrobial additive , and / or fire retardant these additives may be added to the polymer binder in a step prior to the polymer binder being combined with particles . However it is possible in some embodiments to add them after the addition of particles . In particular, addition of the thickener after addition of the particles may of fer functional benefits .

[0056] Suitably the particles are wetted with water prior to mixing with the polymeric binder and prevent the binder from drying too quickly . Wetting may comprise , for example , immersing the fibres in water, or moistening them with a water spray, or holding them in a humid environment .

[0057] The method may comprise the step of masking fittings associated with a room . Examples of these fitting may include but are not l imited to radiators , skirting boards , windowsills and window frames . Thi s beneficially allows for simple retrofitting of the insulation material .

[0058] The method may further comprise a step of combining particles and a polymer binder into a pressurised container . This may facilitate the application of the insulation material onto a surface by spraying .

[0059] The method may comprise the step of inj ecting air into the insulation material .

[0060] The method may comprise the step of atomising the insulation material .

[0061] The method may further comprise a step of spraying the insulation material onto a substrate .

[0062] The substate may comprise a wall , surface , ceiling and / or floor .

[0063] The method may comprise a step of spraying the insulation material onto a substrate such that a layer of the insulation material is formed .

[0064] Alternatively or additionally to spraying, the insulating material may be applied onto a substrate using a float and / or trowel ; and / or or smoothed flat using a float and / or trowel . To facilitate this method the insulating material may be provided in a container .

[0065] Preferably, the insulation material has viscosity such that there is no creep on the substrate after the material is applied . The material may be applied within a temperature range of 0-30 ° C . As noted above a thixotropic agent may be present , and when it is present can assist the material to be free- flowing when it is being sprayed, but stable on the substrate once sprayed .

[0066] Preferably, this layer is between 2-25 mm thick . More preferably, the layer is between 4 and 15 mm thick . Even more preferably, the layer is between 6 and 12 mm thick .

[0067] The method may further comprise a step of allowing the insulation material to dry . Preferably, the insulation material is dried by evaporation at ambient room temperature .

[0068] Alternatively, or in addition, the insulation material may be dried using a fan and / or a heater . Preferably, the insulation material is touch dry after 4 hours .

[0069] The method may further comprise the step of skimming over the dried insulation material with plaster . A 'breathable ' plaster many suitably be employed, to provide some air permeability .

[0070] Beneficially, the insulation material can be used in new- build structures and can also be retrofitted in existing structures . Due to the method of application, the insulation material may be retrofitted without the need for sockets and or skirting boards to be removed . This is because the insulation material only forms a thin layer of insulation and can be guided with suf ficient precision with a spraying device , such as a spray gun, or by use of a trowel and / or float .

[0071] The invention may include any combination of the features or limitations referred to herein, except such a combination of features as are mutually exclusive , or mutually inconsistent .

[0072] Embodiments of the present invention will now be described, by way of example only .

[0073] Example 1

[0074] Example 1 of the insulation material employed 10% wt / wt of sheep' s wool fibres milled to an average fibre length 200 pm, and having a fibre thickness of 10-30 pm and 85% wt / wt of styrene-acrylic water emulsion ( Texicryl 13- 601 ( Trade Mark) from Scott Bader Inc of San Jose , USA) , and 5% wt / wt of fumed silica (Aerosol 200 ( Trade Mark) from Sigma Aldrich) as thixotropic agent . The material is produced by separately mixing the fumed silica with the emulsion, and then mixing the wool fibres with the emulsion in situ . The resulting insulation material is decanted into a spraying vessel and is sprayed onto a substrate to which it sticks and forms a 6 mm thick layer . The insulation material dries over a period of 4 hours at ambient room temperature . The fumed silica allows the material to be sprayed but stays in place on the wall without running or creeping .

[0075] Example 2

[0076] Example 2 of the insulation material contained 5% wt / wt of sheep' s wool fibres of the grade used in Example 1 , 93% wt / wt of styrene-acrylic water emulsion ( Texicryl 13- 601 ) , 1 % wt / wt of an inverse emulsion thickener (Texipol 63-202 (Trade Mark) from Scott Bader) . The material was produced by mixing the thickener with the emulsion, and then mixing in prewetted wool fibres. The insulation material was formulated for application to walls by trowelling.

[0077] The insulating material was formed into a panel of thickness and allowed to dry fully. The insulating material was easy to apply and gave a smooth surface.

[0078] The panel was tested for thermal resistance using a FOX 200 thermal meter (Trade Mark) from Waters Ltd., of Wilmslow, UK. For the testing, the panel was placed between two panels of plasterboard, to mitigate stray surface effects. Laboratory conditions were controlled at 23°C, relative humidity of 65%.

[0079] The thermal conductivity, an average of three replicates, was measured in the through-thickness direction as 0.052 W / mK.

[0080] Example 3

[0081] Example 3 of the insulation material contained 10% wt / wt of sheep's wool fibres of the grade used in Example 1, 89% wt / wt of styrene-acrylic water emulsion (Texicryl 13-601) , 1% wt / wt of an inverse emulsion thickener (Texipol 63-202 (Trade Mark) from Scott Bader) . The material was produced, applied and tested as described in Example 2. The thermal conductivity was 0.054 W / mK.

[0082] Example 4

[0083] Example 4 of the insulation material contained 25% wt / wt of sheep's wool fibres of the grade used in Example 1, 85.25% wt / wt of styrene-acrylic water emulsion (Texicryl 13-601) , 1% wt / wt of an inverse emulsion thickener (Texipol 63-202 (Trade Mark) from Scott Bader) . The material was produced, applied and tested as described in Example 2. The thermal conductivity was 0.051 W / mK.

[0084] Example 5

[0085] Example 5 of the insulation material contained 17.5% wt / wt of sheep's wool fibres of the grade used in Example 1, 81.5% wt / wt of styrene-acrylic water emulsion (Texicryl 13-601) , 1% wt / wt of an inverse emulsion thickener (Texipol 63-202 (Trade Mark) from Scott Bader) . The material was produced, applied and tested as described in Example 2. The thermal conductivity was 0.049 W / mK.

[0086] Further, Example 5 was assessed for void formation within the dried insulation material. A cross-section cut through the plane of the panel revealed a dense array of voids. Visual inspection suggests that the voids are a millimetric scale; or at least on a scale at least one order of magnitude greater the scale of the wool fibres. A photomicrograph if the cross-section is shown as Fig. 1.

[0087] Example 6

[0088] In this example insulation material comprised 25% wt / wt of sheep's wool fibres of the grade used in Example 1, and 70% wt / wt of styrene-acrylic water emulsion (Texicryl 13-601 (Trade Mark) from Scott Bader Inc of San Jose, USA) , and 5% wt / wt of fumed silica (Aerosol 200 (Trade Mark) from Sigma Aldrich) as thixotropic agent. The material was produced by separately mixing the fumed silica with the emulsion, and then mixing the wool fibres, pre-wetted, with the emulsion in situ. The resulting insulation material is decanted into a spraying vessel and is sprayed onto a substrate to which it sticks and forms a 6 mm thick layer . The insulation material dries over a period of 4 hours at ambient room temperature . The fumed silica allows the material to be sprayed but stays in place on the wall without running or creeping .

[0089] Example 7

[0090] In this example insulation material comprised 10% wt / wt of j ute fibres milled to an average fibre length 200 pm, and having a mean fibre thickness of 17-20 pm, and 87 % wt / wt of styrene-acrylic water emulsion ( Texicryl 13- 601 ( Trade Mark) from Scott Bader Inc of San Jose , USA) , and 3% wt / wt of fumed silica (Aerosol 200 ( Trade Mark) from Sigma Aldrich) as thixotropic agent . The material was produced by separately mixing the fumed silica with the emulsion, and then mixing the j ute fibres , pre-wetted, with the emulsion in situ . The resulting insulation material is decanted into a spraying vessel and is sprayed onto a substrate to which it sticks and forms a 6 mm thick layer . The insulation material dries over a period of 4 hours at ambient room temperature . The fumed silica allows the material to be sprayed but stays in place on the wall without running or creeping .

[0091] Whilst endeavouring in the foregoing speci fication to draw attention to those features of the invention believed to be of particular importance , it should be understood that the applicant claims protection in respect of any patentable feature or combination of features referred to herein, and / or shown in the drawings , whether or not particular emphasis has been placed thereon .

Claims

CLAIMS1 . An insulation material to be applied to a substrate , the material comprising particles and a polymeric binder .2 . An insulation material according to Claim 1 , wherein the polymeric binder is a polymer emulsion .3 . An insulation material according to Claim 2 , wherein the polymeric binder comprises a bio-derived polymer .4 . An insulation material according to Claim 3 , wherein the polymeric binder is at least one of a bio-derived acrylic, a bio-derived styrene-acrylic, a bio-derived polyurethane , a bio-derived poly (vinyl acetate-co- ethylene-co-vinyl-ester ) , a bio-derived poly ( ethylene- co-vinyl ester-co-acrylic acid) , and / or a bio-derived poly (vinyl chloride-co-ethylene-co-vinyl ester ) .5 . An insulation material according to Claim 1 or 2 , wherein the polymeric binder may comprise a synthetic polymer or resin .6 . An insulation material according to Claim 5 , wherein the binder is at least one of an acrylic, a styrene- acrylic, a polyurethane , a poly (vinyl acetate-co- ethylene-co-vinyl ) , a poly ( ethylene-co-vinyl ester-co- acrylic acid) , and / or a poly (vinyl chloride-co- ethylene-co-vinyl ester ) .7 . An insulation material according to Claim 2 , wherein the emulsion is a water-based polymer .

8. An insulation material according to Claim 7, wherein the emulsion is a polymer-in-water emulsion.

9. An insulation material according to any preceding claim, wherein the polymer binder does not require a curing agent to set.

10. An insulation material according to any preceding claim, wherein the particles may be derived from animal sources, for example from animal fleeces, or from shells; or from plant sources, for example being particles of wood, bark, bamboo, cellulose, hemicellulose, cotton, sisal, flax, hemp and jute; or from inanimate sources, for example being particles from rocks and minerals, or from synthetic polymeric materials .

11. An insulation material according to any preceding claim, wherein the particles comprise fibres.

12. An insulation material according to Claim 11, wherein the fibres are from animals' fleeces.

13. An insulation material according to Claim 12, wherein the fibres are from wool.

14. An insulation material according to any of Claims 11 to 13, wherein the mean length of the fibres is of 40 pm to 1 mm in length suitably 50 pm to 500 pm in length, for example 60 pm to 250 pm in length.

15. An insulation material according to any preceding claim, wherein the insulation material comprises at least one of: a thixotropic agent, a thickening agent, a pH regulator, a hydrophobic agent, a mineral filler,a defoamer, an antimicrobial additive and / or a fire retardant .16 . An insulation material according to any preceding claim, wherein the insulation material is non-metal lic .17 . An insulation material according to any preceding claim, wherein there are voids within the insulation material .18 . An insulation material according to Claim 17 , wherein the polymeric binder and the particles are such that voids form naturally as insulation material sets .19 . An insulation material according to Claim 17 or 18 , wherein the interfacial attraction between the particles and the polymer binder is modi fied such that voids are formed which otherwise would not be present ; or such that the morphology of voids is changed; or such that the total volume of voids per given volume of binder may be increased .20 . An insulation material according to Claim 19 , wherein the interfacial attraction between the particles and the polymer binder is modi fied by subj ecting the particles to plasma treatment .21 . An insulation material according to any of Claims 17 to 20 , wherein the voids constitute from 1 to 30 % vol / vol , of the insulation material , when set ; preferably from 2 to 20 % vol / vol , and preferably from 3 to 10 % vol / vol .22 . A kit comprising particles and a polymeric binder that produces an insulation material when delivered incombination to a substrate ; the kit being as claimed in any preceding claim .23 . A method of applying an insulation material to a substrate , the insulation material comprising particles and a polymer binder, and being as claimed in any of Claims 1 to 21 , the method comprising a step of combining particles with a polymer binder to produce the insulation material .24 . A method according to Claim 23 of applying an insulation material to a substrate , wherein the insulation material formed as a layer between 2 and 25 mm thick, suitably between 4 and 15 mm thick, for example between 6 and 12 mm thick .25 . A method according to Claim 23 or 24 , of applying an insulation material to a substrate , wherein the method comprises a step of allowing the insulation material to dry on the substrate .26 . A method according to any of Claims 23 to 25 of applying an insulation material to a substrate , wherein the insulation material is dried by at least one of : evaporation at ambient room temperature ; use of fan; or use of a heater .27 . A method according to any of Claims 23 to 26 , of applying an insulation material , wherein the method further comprises a step of skimming over the dried insulation material with plaster .

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