The class of hollow glass microspheres selected for a masterbatch depends on the end use of the TPO component. For example, the pressures involved in TPO molding require hollow glass microspheres with elevated crush strength. Hollow glass microspheres strength is generally proportional to density, and thus lower-strength bubbles are less dense, and offer greater potential for TPO weight reduction than thicker-walled, higher-strength bubbles.

Hollow glass microspheres size impacts TPO surface finish as well as stress transmission through the composite, with smaller bubbles contributing to more favorable impact and tensile properties. In general, higher-strength bubbles are required for injected molded interior and exterior automotive components, and other industrial components.

The modulus (stiffness) of a part also increases in proportion to the ratio of hollow glass microspheres to resin. The positive attributes of increased stiffness and heat distortion temperature (HDT) as well as decreasing coefficient of linear thermal expansion (CLTE), shrink, warp, and sink marks continue to improve as the percentage of hollow glass microspheres in the resin mix rises. Tensile strength, elongation, and impact strength tend to decrease as well. Complementary additives in the masterbatch can modify these values to some degree.

In general, plastics are flexible and experience ductile failure under stress, while glass adds stiffness but is more prone to brittle breakage, It is possible to improve TPO impact strength by adding an impact modifier to the masterbatch that reduces potential for brittle failure while maintaining the stiffness advantage.

The concentration of hollow glass microspheres in a masterbatch additive mix varies, but can be as much as 50% by weight, depending on customer requirements. Finished parts made using this masterbatch hollow glass microsphere concentration will be 20% or more lighter than resin-only parts.

Process tests show that a Noble masterbatch formulation with hollow glass microspheres can cut TPO injection molding production time as much as 20%. This benefit is apparently related to changes in thermal properties that result from displacing resin with hollow glass (reduced mass), and the resulting time savings are concentrated primarily during the cooling period.”

This article comes from plasticstoday edit released

Polyethylene microspheres (also referred to as polyethylene spheres, beads, balls, polymer spheres, polymer microspheres, polymer beads, plastic beads or plastic microspheres) are solid spherical microparticles and are the most common type of solid polymer spheres. Hollow glass microspheres represent a class of additives that offer aesthetic, process control and cost benefits, while providing flexibility in a wide range of potential applications. With advances in microsphere manufacturing processes, polymer spheres and hollow glass microspheres are available in comparable grades, particle sizes and prices.

Which microsphere material is right for your application? There are several major differences to keep in mind when selecting microspheres.

1) Melting Point:

Polyethylene Microspheres – The melting point of polyethylene microspheres varies somewhat depending on the grade and molecular weight of the polymer, but is usually between 110C for low molecular weight grades and 130C for higher molecular weight material. The melting point is typically low and sharp, since polyethylene goes through a fast phase transition. This is a very important feature for applications where the spheres are used as a temporary filler but would need to be “melted away” at a later point to create holes or cavities for a sponge effect.

Hollow glass microspheres – The melting point of hollow glass microspheres is from 500C – 800C, depending on the product. High melting point makes hollow glass microspheres attractive for high temperature applications, where the product needs to withstand severe environmental or processing conditions.

2) Density or Specific Gravity of Particles:

Polyethylene Microspheres – Typical densities of 0.95 g/cc – 1.3 g/cc as well as ability to color-code spheres by density make polyethylene spheres suitable as density marker beads. These are small colored microspheres of known mass density that are used for calibrating density gradients and determining density in gradient columns. Density gradients are often used for separations and purifucations of cells, viruses and subcellular particles. Generally a set of several density marker beads covering a range of densities is used. Custom density particles are available in polyethylene formulations. Brightly colored and fluorescent polymer microspheres are specifically designed as particles for water flow visualization and particle image velocimetry (PIV) experiments. Highly spherical microbeads with tight particle size distribution and density of 1g/cc, matching to properties of fresh water, are used as tracer or seeding particles clearly visible as they follow the flow of the liquid.

Hollow glass microspheres – Solid hollow glass microspheres have a high density of about 2.2g/cc for borosilicate hollow glass microspheres, 2.5g/cc for soda lime hollow glass microspheres, and 4.49g/cc for barium titanate hollow glass microspheres. Hollow glass microspheres have densities as low as 0.14 g/cc.Depending on the application requirements, solvents used, desired buoyancy, difference in density between polyethylene and glass microspheres might become a critical factor when selecting the right material.

3) Chemical Stability:

Polyethylene Microspheres – Most grades of polyethylene have excellent chemical resistance and do not dissolve at room temperature because of their crystallinity. Polyethylene microspheres usually can be dissolved at elevated temperatures in aromatic hydrocarbons such as toluene or xylene, or in chlorinated solvents such as trichloroethane or trichlorobenzene. This feature is benefitial if microspheres need to be dissolved at a precise point in the process.
Hollow glass microspheres – Glass has very high chemical resistance and is the right choice for applications where microspheres need to withstand contact with agressive solvents at elevated temperatures.

This article comes from cospheric edit released

Hollow glass microspheres have been used as low-density fillers for various kinds of polymeric compounds since the mid-1960s. For the first 20 years after their introduction, hollow glass microspheres weren’t strong enough to survive the high shear forces and high pressures involved in plastics compounding and injection molding.

Hollow glass microsphere, has the highest compressive strength in the world for such a product. It also has the highest strength-to-density ratio of any glass or other microsphere in the marketplace. Made from soda/lime borosilicate, it can withstand injection molding pressures up to around 30,000 psi.

Relative to earlier glass microspheres, the improved mechanical properties imparted by hollow glass microsphere include better impact strength and elongation, prevention of scratch or stress whitening, tighter tolerances for small parts, and improved surface finish on the end product due to better packing. Greater crush strength means there is much less breakage of the hollow glass microspheres during extrusion or injection molding.

This article comes from ptonline edit released

Polyethylene Microspheres – Pigments, additives, specialty ingredients can be incorporated into polyethylene prior to microsphere manufacturing process. This allows endless possibilities for customization of polyethylene microspheres for specific applications, smaller R&D projects, and unique customer requirements. Colored, fluorescent, phosphorescent, charged, paramagnetic polyethylene microspheres are available.

Hollow glass Microspheres – In general, it is very difficult to incorporate additives into glass. Formulating with a small percent of additives is sometimes possible, but typically additives interfere with the formation of glass and hinder its inherent properties (such as clarity, sphericity, strength, etc). Customization of microspheres with pigments and additives is limited.

Solid glass imparts visual and material benefits that cannot be replicated when spheres are made of other materials such as ceramics or polymerics, aluminum oxides, or silicas and mineral fillers. Solid glass refracts, bends and reflects light. Most ceramics do not transmit light or exhibit mirror-like reflection due to their internal crystalline structures and surface irregularities. Instead of being reflected back, the light is “trapped” in the structure and emitted as diffuse or scattered reflectance, which is not as strong or direct as light transmitted through glass, which produces mirror-like reflectance. Hollow glass microspheres can also possess numerous surface and interior micro irregularities that also diffuse light. Because the thickness of a hollow bead’s wall is inversely proportional to its diameter, however, the larger hollow spheres that might offer some reflective properties have very low crush strengths, which precludes their incorporation into most formulations.

Solid hollow glass microspheres can be made retroreflective by applying a half-shell aluminum coating applied to solid barium titanate hollow glass microspheres. Retroreflective microspheres are hemispherically coated with a thin aluminum shell to produce a bright retroreflective response directed back to the light source and to the observer. The light bounces off the aluminum-coated half of the sphere produces the retro reflective effect that provides the desired high visibility in dark conditions.

This article comes from cospheric edit released

Hollow Glass Microspheres are high-strength, low-density additives made from water resistant and chemically-stable soda-lime-borosilicate glass.

These hollow glass microspheres offer a variety of advantages over conventional irregularly-shaped mineral fillers or glass fiber. Their spherical shape helps reduce resin content in a variety of applications. They also create a ball bearing effect that can result in higher filler loading and improved flow. In this research, amine terminated hollow glass microspheres were prepared by adopting three different routes.

The results were investigated using FT-IR and SEM to establish the formation of amine groups and observe the morphological structure of the modified HGMs. The results obtained were used to select a suitable less toxic and environmental friendly modification method based on the chemicals used.

This article comes from scientific research edit released

Polyurethanes (or urethane polymers) are one of the most versatile materials used today for numerous applications ranging from flexible foam in upholstered furniture to rigid foam as insulation in walls, roofs, and pipes.

To thermoplastics used in medical devices and footwear; to coatings, adhesives, sealants, and elastomers used on floors and automotive interiors.

In this chapter, the use and benefits of hollow glass microspheres in thermoplastic, thermoset, and foam polyurethane system are described.

This article comes from sciencedirect edit released

These bulking agents are hollow glass microspheres that make a low cost, low density filler. Added to epoxy resin and hardener mix, they make a good, heat-resistant, light-weight fairing compound with good compressive strength. Mixture can be blended with a small amount of Silica Thickener to prevent sagging.

Not recommended for glue, alternatively use SilverTip QuikFair for ease-of-use.

This article comes from systemthree edit released

This is a white-colored, fused borosilicate glass in a hollow microsphere or bubble form. This product has a bulk density of 0.26 g/cc and a maximum working pressure of 4,000 psi.

Hollow glass microphere is most commonly used to increase thermal and acoustic insulation in autobody sealant and coating applications.

Sphericel hollow glass microspheres are used as lightweight additives in plastic parts as well as to enhance performance and reduce viscosity in paints and coatings.

Hollow glass micropheres are chemically inert, non-porous, and have very low oil absorption.

This article comes from thecarycompany edit released

Rapid development in the field of deep-sea exploration in the middle of the 20th century was one of the main reasons for development of hollow glass microsphere (HGM) technology. Development engineers of deep submergence vehicles required new structural materials with densities less than those of water but of high compression strength and water resistance. Syntactic composites based on HGMs were able to meet these requirements. Structural elements made using these materials are capable of withstanding water pressure down to 6000 m.

Hollow glass microspheres form a white coloured powder consisting of tiny bubbles with diameters ranging between 20-150 μm with walls thicknesses less than 1 μm. The glass composition and the near perfect spherical shape of the microspheres provide high compressive strength. The main distinction between high and low grade HGMs is their shape and structure. Lower quality HGMs fail under less load, less predictably, compared to high grade HGMs. Other key properties include low water absorption, low heat conductivity, high chemical resistance and radio transparency.

Good adhesion of HGMs towards polymer binders makes them ideal for composites giving a unique combination of properties. All the above-mentioned factors define a wide variety of applications for HGMs.

The technology for HGM manufacture is a combination of complex hydrodynamic and chemical processes that take place in the course of forming of hollow bubbles blown from microparticles of glass melt. An exact dosage of gas into the melted powder blows microspheres with the required diameter and wall thickness. With such a complex technological process it is impossible to make microspheres with a strictly identical predetermined diameter. Therefore calibration of microspheres is performed according to their dimensions. The strength of the microspheres is established by testing the hydrostatic pressure at which not more than 10% of the HGMs fail. It is natural that microspheres with a greater density – and thus with thicker walls – are stronger.

This article comes from materialstoday edit released

Hollow Glass Microsphere is a kind of hollow spherical powdered ultralight inorganic nonmetallic materials.

The Properties of Hollow Glass Microsphere

Pure white color, Hollow Glass Microsphere can be widely used in products which have high requirements for looks and colors.

Low density, reducing the products’basic weight obviously after filling. (the density of HGS is one out of a dozen of traditional filler particles’ density). Relatively large volume, which can substitute and save more resins, reducing cost.

High dispersion and good fluidity, dimensional stability, reduced warpage and shrinkage when used as additives.

Heat insulation, sound insulation, mostly used as heat insulation paints and coatings, automotive sealants.

In addition, corrosion resistant, fire resistant, non-conducting.

Application Area

a. lightweight cement, low-density oil well cementing slurry & low-density drilling fluids additive.
b. low-density FRP(fiberglass-reinforced plastic), SMC, BMC composites.
c. low-density adhesives & sealants
d. heat insulation paints and coatings
e. Construction (reducing warpage/shrinkage)
f. Insulation and Buoyancy
g. artificial marble

Our hollow glass microspheres can be used in paint and coatings, construction sealant, rubber, plastic, FRP, artificial stone, putty and other products as filler and weight-reducing agent. The glass bubbles can also be used to produce high-strength, low-density cement slurry and low-density drilling fluid in oil and gas extraction industry. more and more industries now trying to testing the hollow glass spheres as additives to improve their products’ properties.

This article comes from hollowlite edit released