IKA A 11.4 grinding beaker, polycarbonate, 250 ml, 0002904100

Kinetics of impact comminution on a scaled volume scale

The comminution of larger sample batches in instrumental analysis requires a tailored fluid-dynamic design. The IKA A 11.4 grinding beaker significantly expands the primary working zone of the A 11 basic analytical mill to a volume of 250 ml. This specific cylinder geometry creates an extended rheological flow space. The high-speed rotation of the grinding tool generates strong hydrodynamic turbulence (vortex) within this chamber. These flow vectors continuously circulate soft to medium-hard solids (such as agricultural products, soft polymers or plant tissue) through the kinetic impact zone of the beater, thereby achieving a homogeneous particle size distribution across the entire batch without any fluid-dynamic dead zones.

Polymer physics and optical process control

To ensure the structural integrity of the system during massive impacts, the A 11.4 grinding bowl is made from amorphous high-performance polycarbonate (PC). This thermoplastic polymer is characterised by extremely high ballistic impact resistance and absorbs kinetic fracture energy more effectively than conventional plastics. However, the key metrological advantage of this material is its absolute optical transparency. The user can visually monitor the macrokinetics of the mixing process and the gradual reduction in particle size in real time. This enables a prompt, physical determination of the ideal grinding interval and prevents excessive thermodynamic stress (exothermic reactions due to friction) on the sample caused by unnecessarily long process times.

Thermomechanical limitations and containment

As a closed system, the A 11.4 beaker acts as hermetic mechanical containment, reliably preventing the aerodynamic dispersion of respirable fine dust or toxic aerosols into the laboratory environment. From a process engineering perspective, however, the thermodynamic threshold of the polycarbonate must be strictly observed: Due to its macromolecular structure, this beaker is strictly excluded from cryogenic grinding. The direct application of liquid nitrogen (LN₂) or dry ice would immediately cool the polymer below its glass transition temperature, causing the thermoplastic matrix to become extremely brittle and, under the radial centrifugal forces, lead to a catastrophic mechanical cold fracture (splintering).

Technical details

• Product type: Large-volume grinding chamber
• Material: Highly transparent polycarbonate (PC)
• Maximum usable volume: 250 ml
• Processing principle: Impact and shock comminution
• Physical scope of application: Soft to medium-hard sample matrices
• Visual benefits: Unobstructed in-situ visualisation of the comminution process
• Health and safety: Acts as a mechanical aerosol containment system
• Thermodynamic limitation: Not approved for cryogenic cooling media
• Compatibility: Suitable exclusively for the IKA A 11 basic analytical mill

Contents of delivery

• 1 x IKA A 11.4 grinding beaker (polycarbonate, 250 ml)

(Important note: The A 11 basic drive unit, grinding tools and housing lid are not included in the scope of delivery!)

Individual requirements & accessories

The A 11.4 polycarbonate beaker is the ideal solution from a process engineering perspective for bulky, soft samples where visual monitoring of the degree of grinding is critical. However, if your laboratory needs to grind hard mineral rocks or if cryogenic cooling media must be used to prevent thermal denaturation, switching to the solid IKA A 11.5 stainless steel grinding beaker (item no. 0002983100) is physically essential. Please contact our procurement service at any time for assistance in selecting the correct grinding vessels based on thermodynamic and materials science criteria.