HL25 Hollow Glass Microsphere for adhesive
HL25 Hollow Glass Microspheres are rigid borosilicate lightweight spherical fillers specially engineered for all types of adhesive systems. Featuring moderate density, reliable crush strength, good dispersibility and stable chemical inertness, HL25 serves as an ideal functional additive to modify epoxy adhesive, polyurethane adhesive, sealant, structural bonding glue and potting compounds.
In adhesive formulations, HL25 hollow glass microspheres bring multiple significant advantages. First of all, they effectively reduce the overall density of adhesives and sealants, realizing lightweight design for finished bonded components. Lower density helps cut raw material costs by replacing expensive resin, while reducing material shrinkage during curing. It greatly minimizes common problems such as internal voids, deformation and cracking caused by volume shrinkage after crosslinking.
The regular spherical morphology of HL25 improves the rheological property of uncured adhesives. It optimizes flow behavior, effectively prevents sagging during construction, and enhances extrudability for manual dispensing and automatic gluing processes. Meanwhile, the microspheres can adjust the thermal expansion coefficient of cured adhesive layers, relieve internal thermal stress under temperature cycles and strengthen the long-term bonding stability.
HL25 maintains intact hollow structure under normal stirring and mixing procedures, without massive particle breakage. Its excellent resistance to weak acid, alkali and moisture ensures stable performance inside adhesive layers under complex service environments. Furthermore, HL25 improves thermal insulation and sound-damping capacity of adhesives and sealants, making them suitable for bonding applications that require both structural strength and thermal or acoustic attenuation.
HL25 is widely applicable to structural adhesives, assembly sealants, electronic potting adhesives, composite bonding agents and marine caulking compounds. When properly matched with resin systems, HL25 hollow glass microspheres balance low weight, processability and mechanical performance, becoming a cost-effective lightweight filler choice for modern adhesive manufacturers.
Chemical composition(%):
| SiO2 | 58-71 |
| Na2CO3 | 12-25 |
| B2O3 | 3-12 |
| Al2O3 | 0-10 |
| CaO | 0.2-1.0 |
| Fe2O3 | 0-0.5 |
| MgO | 0-0.05 |
Physical Index:
| True Density | 0.18-0.60g/cm3 |
| Bulk Density | 0.10-0.34g/cm3 |
| Crush Strength | 4-125Mpa/500-18000Psi |
| Survival | Min 90% |
| Flotation | Min 92% |
| Moisture | Max 0.5% |
| Particle Size | D50:20-70um |
| Max. Particle Size: | 200um |
| Melting Point | 1600°C |
Specifiction:
| Spec. | True Density(g/cm3) | Bulk Density(g/cm3) | Compressive strength(Mpa/Psi) | D50(um) | D90(um) | Packing(Kgs) |
| HL15 | 0.13-0.17 | 0.08-0.09 | 4/500 | 65 | 120 | 8 |
| HL20 | 0.20-0.22 | 0.10-0.12 | 4/500 | 65 | 110 | 10 |
| HL25 | 0.24-0.27 | 0.13-0.15 | 5/750 | 65 | 100 | 12.5 |
| HL30 | 0.29-0.32 | 0.15-0.18 | 10/1500 | 55 | 85 | 15 |
| HL32 | 0.31-0.33 | 0.17-0.19 | 14/2000 | 45 | 80 | 15 |
| HL35 | 0.33-0.37 | 0.18-0.21 | 21/3000 | 40 | 70 | 15 |
| HL38 | 0.37-0.39 | 0.19-0.22 | 38/5500 | 40 | 65 | 20 |
| HL40 | 0.39-0.42 | 0.19-0.23 | 28/4000 | 40 | 70 | 20 |
| HL42 | 0.41-0.44 | 0.21-0.24 | 55/8000 | 40 | 60 | 20 |
| HL46 | 0.44-0.48 | 0.23-0.26 | 41/6000 | 40 | 70 | 22.5 |
| HL50 | 0.48-0.52 | 0.25-0.27 | 55/8000 | 40 | 60 | 25 |
| HL55 | 0.53-0.55 | 0.27-0.29 | 68/10000 | 40 | 60 | 25 |
| HL60 | 0.58-0.62 | 0.29-0.34 | 83/12000 | 40 | 65 | 30 |
| HL60S | 0.58-0.63 | 0.30-0.34 | 125/18000 | 35 | 55 | 30 |
| HS38 | 0.37-0.39 | 0.19-0.22 | 38/5500 | 30 | 50 | 20 |
| HM10 | 1.4-1.6 | 0.45-0.50 | 193/28000 | 5 | 10 | 30 |
| HM15 | 1.2-1.3 | 0.40-0.45 | 124/18000 | 7 | 15 | 30 |
| HM20 | 1.05-1.15 | 0.39-0.44 | 124/18000 | 9 | 20 | 25 |
| HM30 | 0.9-1.0 | 0.35-0.4 | 83/12000 | 14 | 30 | 25 |
| HS20 | 0.18-0.22 | 0.10-0.12 | 7/1000 | 60 | 90 | 10 |
| HS22 | 0.20-0.24 | 0.11-0.13 | 8/1200 | 45 | 70 | 10 |
| HS28 | 0.27-0.30 | 0.15-0.17 | 28/4000 | 45 | 65 | 15 |
| HS38 | 0.36-0.40 | 0.19-0.22 | 38/5500 | 30 | 50 | 20 |
| HS42 | 0.40-0.44 | 0.21-0.24 | 55/8000 | 25 | 40 | 20 |
| HS46 | 0.44-0.50 | 0.22-0.25 | 110/16000 | 20 | 30 | 22.5 |
| HS60 | 0.58-0.62 | 0.29-0.33 | 193/28000 | 16 | 25 | 30 |
| HS65 | 0.63-0.67 | 0.30-0.33 | 207/30000 | 13 | 20 | 32 |
| HS70 | 0.75-0.80 | 0.33-0.35 | 207/30000 | 10 | 15 | 35 |






