Archive for the ‘Hollow Glass Microspheres’ Category

This new type of hollow glass microspheres are low in density and high in strength, which are able to resist high temperature and acid / alkali corrosion, and show low thermal conductivity and nice electrical insulation.

Hollow glass microsphere is a cross-functional frontier material that can be added to a variety of substrate materials to improve their performances (such as weight-reduction) and environmental benefits (such as building thermal insulation).

Especially under the background of striving to achieve the “carbon peak” and “carbon neutralization” goal, researching and promoting the application of multi-specification hollow glass microspheres in building paints, industrial coatings, cementing slurry, sealants and adhesives, modified plastics, rubber-based products, epoxy tooling board, emulsion explosives, artificial stones and other fields, is of great strategic significance to carbon emission reduction, chemicals storage, aviation and aerospace, petroleum and natural gas mining, 5G communications and military industry for our country.

Screening hollow glass microspheres can be an extremely difficult and tedious process. It requires a combination of technology and technique in order to make the required separations.

The main issue when screening hollow glass microspheres is coating of the screen mesh. The material is so light that it almost floats on the screen and has a hard time passing through the hole opening.

Furthermore, the ingoing feed must closely be metered to avoid overloading the screen.

Global warming can be defined as a gradual increase in the overall temperature of the earth’s atmosphere. A lot of research work has been carried out to reduce that heat inside the residence such as the used of low density products which can reduce the self-weight, foundation size and construction costs.

Foamed concrete it possesses high flow ability, low self-weight, minimal consumption of aggregate, controlled low strength and excellent thermal insulation properties. This study investigate the characteristics of lightweight foamed concrete where Portland cement (OPC) was replaced by hollow glass microsphere at 0%, 3%, 6%, 9% by weight. The density of wet concrete is 1000 kg/m3 were tested with a ratio of 0.55 for all water binder mixture. Lightweight foamed concrete hollow glass microsphere (HGMs) produced were cured by air curing and water curing in tank for 7, 14 and 28 days. A total of 52 concrete cubes of size 100mm × 100mm × 100mm and 215mm × 102.5mm × 65mm were produced.

Furthermore, Scanning Electron Microscope (SEM) and X-ray fluorescence (XRF) were carried out to study the chemical composition and physical properties of crystalline materials in hollow glass microspheres. The experiments involved in this study are compression strength, water absorption test, density and thermal insulation test.

The results show that the compressive strength of foamed concrete has reached the highest in 3% of hollow glass microsphere with less water absorption and less of thermal insulation. As a conclusion, the quantity of hollow glass microsphere plays an important role in determining the strength and water absorption and also thermal insulation in foamed concrete and 3% hollow glass microspheres as a replacement for Portland cement (OPC) showed an optimum value in this study as it presents a significant effect than other percentage.

Hollow glass microspheres are a free-flowing, oleophilic product that is low in density (0.19g/cm3 ) and small in particle size (75µm, avg). This product is especially suited for use in adhesive applications.

When hollow glass microsphere is added to a “workhorse” epoxy resin system (bisphenol-A, cured with a modified aliphatic amine) at volume levels of 9 and 18%, resin density is reduced substantially, while lap-shear adhesive strength is retained, and in some cases, improved.

Additionally when used to augment the same resin system containing conventional solid fillers (calcium carbonate with fumed silica), hollow glass microspheres impart similar benefits. The data collected in the study illustrate the benefits gained from the use of hollow glass microspheres in the epoxy system.

Benefits include:

• Formulation density reduction, leading to cost savings.

• Maintenance of adhesive performance, potential improvement in bond strength at ambient temperatures and after exposure to elevated temperature stress.

• Viscosity optimization of the formulation, aiding in sag prevention and development of adequate “glue-line”.

These types of plastics are made by melt blending that includes Poly PCL which has hollow glass microspheres incorporated inside them. Further, with the added effect of treatments such as silanization on the hollow glass sphere, there is a difference brought in the properties of the silanized sphere vs. the unsilanized sphere. The analysis with silanization reflects that the dissemination of glass particles in the matrix of polymer in every case of a filer which is good, the silanized hollow glass microsphere showed a matrix adhesion.

In terms of its thermal nature, it is shown that the rate of crystallization is significantly enhanced and the stability also is enhanced as compared to a PCL without hollow glass microspheres. By adding the hollow glass sphere the mechanical nature of the product is altered which leads to an increase in the stiffness of the material. The tensile strength especially enhances quite significantly in comparison to untreated PCL. This behaviour observes by the hollow glass microsphere filled composites is the tensile strength is enhanced and with the addition of a silane agent the matrix adhesion is also improved.

Research shows that by incorporating 20% wt. of hollow glass microsphere the density is decreased by about 12% compared to a PCL without microspheres. With plastics the lightweight materials when reduced in density do not lose out on any mechanical properties, it remains intact. Hollow glass microspheres in this regard are one of the most effective and very affordable glass microspheres which have multiple uses.

One of the main goals when designing a part, a tool, and a processing method utilizing hollow glass microspheres is to minimize shear stresses to avoid crushing the spheres. Lack of proper attention to this factor may result in sharply reduced properties in the end product and increased part weight.

A single-screw design for incorporating iM30K microspheres into thermoplastic resins should contain a dispersive mixing element, which typically serves to break up agglomerates of fine particles. Examples of such mixing elements are the classic Maddock mixer (a fluted cylinder) or Saxton mixer (a densely flighted screw with a crosscut through the flights), though many others are available. The screw design should also have a distributive mixing element, which usually involves pin mixing sections.

In single-screw extruders, the iM30K microspheres should be added at a downstream feed port after the resin has been melted, just before the beginning of the metering zone, to minimize potential breakage of the spheres. They are added before the distributive mixing elements, in the middle of the compression section of the screw.

To mold polymers filled with hollow glass microspheres, a general-purpose injection screw is best. Other types of screws—like barrier, double-vane, or vented—are not recommended for processing hollow glass microspheres. The minimum diameter of the screw should be 1.5 in.

When molding with hollow glass microspheres, low backpressure of around 10 to 50 psi should be used. The hollow glass microspheres within the molten resin are apt to break when exposed to excessive injection speed and pressure. The injection speed should be kept low to medium. Unlike with previous microspheres, which limited cavity pressures to 10,000 psi, iM30K spheres can withstand 20,000 psi or more.

A variety of gates can be used, but to retain the hollow glass microspheres’ integrity, minimum gate width should be 0.06 in. As stated earlier, S-7 and H-13 type mold steels are recommended for producing parts filled with hollow glass microspheres.

Composites suitable for rotational molding technology based on poly(ε-caprolactone) (PCL) and filled with hollow glass microspheres or functionalized hollow glass microspheres were prepared via melt-compounding. The functionalization of hollow glass microspheres was carried out by a silanization treatment in order to improve the compatibility between the inorganic particles and the polymer matrix and achieve a good dispersion of hollow glass microspheres in the matrix and an enhanced filler–polymer adhesion.

The crystallization behavior of materials was studied by DSC under isothermal and non-isothermal conditions and the nucleating effect of the hollow glass microspheres was proven. In particular, the presence of silanized hollow glass microspheres promoted faster crystallization rates and higher nucleation activity, which are enhanced by 75% and 50%, respectively, comparing neat PCL and the composite filled with 20 wt% hollow glass microsphere.

The crystalline and supermolecular structure of PCL and composites crystallized from the melt was evaluated by WAXD and SAXS, highlighting differences in terms of crystallinity index and structural parameters as a function of the adopted crystallization conditions.

Hollow glass microsphere that also known as vitrified small ball is a kind of micron-sized hollow sphere with smooth surface, its main chemical composition is soda lime borosilicate glass, and the natural accumulation state of them is white light inorganic powder. Composition and hollow structure endow the microspheres with unique properties different from other inorganic non-metallic or hollow materials.

In addition to low density, high compressive strength, high temperature or corrosion resistance, low thermal conductivity, nice fluidity and chemical stability, advantages such as non-toxic, odorless, electric insulation, sound-proofing, anti-radiation, self-lubrication and easy surface modification are also showed by hollow glass microspheres.

These characteristics make hollow glass microspheres widely used as additives in many fields, such as water-based lightweight building insulation paint, low-density drilling fluids and cementing slurry, lightweight components in aerospace and vehicles, ship floating block and coatings, electronic components, high molecular composite materials, putty powder, artificial marble, and natural / synthetic products, etc.

Nowadays, hollow glass micropheres composites are also an object of study in additive manufacturing, such as 3D printing, to improve flow melting and thermal insulation. Özbay and Serhatlı studied processing and properties of different combinations of hollow glass microphere filled with polyamide 12 (PA12) matrix, by Selective Laser Sintering (SLS) manufacturing method. As a result, they obtained a 20% of density reduction and a significant rise in the E-modulus with the composition PA12/hollow glass microphere (80/20).

In the automotive industry, the polyamide (PA6) and polyamide 6.6 (PA66) are often used because of their typical hydrogen bonds, due to their polar chemical structure, with a short GF reinforcement, commonly 30 wt%. Composites of PA6 or PA66 reinforced with glass fibers ensure great mechanical and thermal properties and can be found in air intake manifolds, rocker covers, radiator end tanks, fuel rails, electrical connectors, engine encapsulation and others. In this sense, GF and hollow glass microphere combination may constitute an excellent solution to combine lower density, dimensional stability, and good mechanical properties. Berman et al. have studied the effects of replacing calcium carbonate (high density filler) with hollow glass microphere (low density filler) in an unsaturated polyester resin matrix sheet molding compound (SMC) reinforced with short GF (10~15 wt%). The composite was fabricated in SMC manufacturing, lay-up and hot pressing. As a result, they obtained a 12% of density reduction but compromised the mechanical properties. Nevertheless, all values of tensile, flexural and impact properties were higher than the corresponding properties of low and ultra-low-density composites reported in the literature.

Thus, the goal of this study was to fabricate a composite based in PA6 reinforced with GF and hollow glass microphere and to investigate the effects of hollow glass microphere content on the density, mechanical properties of the composites comparing its properties with the traditional PA6/GF (70/30) wt% composite, widely used today in automotive industries. It’s expected to find a formulation with at least 10% density reduction and maintenance of mechanical properties. In this paper, fundamental results for understanding the relationship between structure and property of both the matrix and the fillers will be discussed in terms of microscopic observations, mechanical properties, and thermal stability.

Hollow glass microspheres, also called bubbles, microbubbles, or micro balloons, provide the benefits of low density, high heat and chemical resistance.

These microscopic spheres of soda-lime/borosilicate glass are low-density particles that are used in a wide range of industries. The hollow microspheres are used to reduce warpage and shrinkage, to adjust the rheological properties, to reduce part weight, and to lower cost.

Hollow glass microspheres have been used as low-density fillers for various kinds of polymeric compounds. Hollow Glass Microspheres for the applications of paint & coating, construction & insulation coating. Due to its excellent advantages of lightweight, bulk density, lower thermal conductivity, higher compressive strength, improved dispersion and liquidity.

Our hollow glass microspheres are genuine and cost-effective alternative having similar specification which have a relative density in the range of 0.15 to 0.20g/cc.