TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The heat conductive material is selected to: enable dissipation of heat generated on the functional component; and have a bulk heat conductivity of quartz or higher than it. The heat conductive material is in the form of heat conductive particles (HCP). The HCP is: electrically insulative or electrically conductive; and also selected to trap humidity collected within the enclosure or to prevent humidity from collecting in that. The heat conductive material is: at least one inorganic material; inorganic HCP comprising molecular sieves, silica gel, calcium sulfate, calcium chloride, silicates, alumosilicates, clay or magnesium sulfate; a filler having an averaged particle size of 0.01-100 microns; molecular sieves, silica gel, calcium sulfate, calcium chloride, metal or non-metal silicates, clay, magnesium sulfate, boron nitride, silicone nitride, metal oxide, an alumosilicate, a metal carbonate, a metal phosphate, a metal sulfate, a metal borate, a zeolite, carbon black or calcium aluminum silicates; silica gel, a zeolite, molecular sieves, clay, carbon or calcium aluminum silicates; or molecular sieves, being optionally made or composed of sodium potassium or calcium alumosilicate. (I) is composed of heat conductive material (5-95 wt.%). The heat conductive material and the desiccant are the same or different. The desiccant is in the form of humidity trapping particles (HTP). The HTP is selected amongst physical desiccants and chemisorbents. The phase change material (PCM) is selected to avoid or minimize heat build-up in the enclosure. The PCM has a high heat capacity of at least 20 kJ/kg, preferably 20-200 kJ/kg. The PCM is further selected to be non-corrosive, low volatility, hydrophobic and have a relatively low modulus of elasticity. The PCM is selected to have a melting point of greater than 20 degrees C, and a heat capacity of greater than 30 kJ/Kg. (I) comprises PCM (0-80 wt.%) and filler (5-95%), where the filler is molecular sieves acting both as HCP and HTP. (I) has: an adhesion to a surface such as glass, metal and silicon; has peel strength to degreased aluminum of at least 1 pound per linear inch (PLI), in accordance with ASTM D903, D395, D1876, and D3167.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: (I) comprises at least one conductive material, at least one desiccant, 5-95 wt.% of at least one thermoplastic and/or thermosetting polymer and optionally at least one of (a) at least one phase change material, (b) at least one monomer and/or oligomer, (c) at least one additive and (d) at least one additional filler. (I) further comprises: at least one PCM; at least one monomer and/or oligomer; and at least one additive. The PCM is selected to have a melting point of the service temperature of the application, where the melting point is at least 10 degrees C, at most 70 degrees C, or 10-70 degrees C. The PCM is paraffin, O-mannitol, methyl palmitate, stearic acid and/or pentaerythritol with paraffin and/or a polyamine, an olefin oligomer, an alcohol, an ester, an amide, an aldehyde, a ketone, a sugar, a glycol, a poly hydroxyl, or a fatty acid. The additive is selected to enable softening of the encapsulant so as to lower stress on the enclosure to be encapsulated and on electrical conductors, and to improved adhesion. The additive is a plasticizer, a tackifier, a silicone oil, a mineral oil, a vegetable oil, a polyhydric alcohol and their esters.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The thermoplastic and/or thermosetting polymer is selected to allow dispersion in that of the HTP, HCP and optionally PCM. The polymer is in the form of a continuous phase. The thermoplastic polymer is: ethylene copolymers and terpolymers, ethylene-vinyl acetate (EVA), ethylene acrylate and methacrylate, ethylene-alpha olefin, styrene ethylene butadiene block copolymer (SEBS), styrene butadiene block copolymer (SBS), styrene isobutylene block copolymer (SIBS), ethylene-propylene, polyester, polyamide, polyurethane, epoxy, vinyl polymer, styrenic polymer, polycarbonate, silicone polymer, silane grafted polyolefin, silane terminated polymer (MS polymer) and polyvinyl butyral, natural rubber, butyl rubber, nitrile rubber, acrylic rubber, polysulfide rubber, chloroprene or neoprene; or polyester, polyamide, polyurethane, epoxy, amino resin, alkyd, silicone, siloxane modified polymer (MS polymer), unsaturated polyester, phenolic resins or vinyl ester. (I) comprises at least one polymer (5-90 wt.%). The polymer is a thermoplastic polymer. The monomer and/or oligomer is acrylic and methacrylic acid and their esters, styrene, isocyanates, diols, polyols, silanes, siloxanes, glycidyl containing compounds and glycidyl ethers and esters, phenolic resins or amino resins. (I) is in a form of a bead, putty, a sheet, a paste or a bulk concentrate. (I) is applied as a sheet having a thickness of 10 microns to 5 millimeters. The sheet is flexible with a low secant modulus of elasticity. The modulus of elasticity, measured at ambient conditions, in accordance with ISO 527-2, is of 0.05-0.25% strain of less than about 250 MPa. The secant modulus of elasticity is less than 100 MPa, or less than 75 MPa. The PV is a silicon module. The substrate is a metallic surface or of a material comprising metallized polymeric film, polymeric film or a polymer composite. EXAMPLE - No suitable example given.