Sunkaier -High Impact Polystyrene (HIPS) System
HIPS (High Impact Polystyrene), also known as PS (Polystyrene), is an amorphous thermoplastic material, used in lower heat applications. It is categorized as a standard material, and offers ease of processing, high impact strength, and stiffness.
HIPS technology is based on a continuous mass peroxide-initiated polymerization of styrene in a rubber-styrene solution.
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Rubber soltion preparation - rubber, after being ground in a mill, is dissolved in styrene in a proper section and then added with chemicals and peroxide in a mixing section.
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Polymerization - this mixture is fed to the polymerization section, generally composed by a sequence of two/three plug-flow reactors; the reaction thermal profile is controlled by thermal oil circulating inside internal coils. The whole reaction section arrangement is selected case-by-case, in order to meet specific requirements.
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At the end of the reaction train, the polymer solution is sent to a devolatilization section, operated in two stages in series under vacuum conditions.
The monomer and low-boiling compounds are removed from the polymer, which is finally sent to the pelletizing unit. The heat is provided by a thermal oil system. The vapour mixture, recovered by the devolatilization section, is condensed and then continuously recycled to the mixing section. Non-condensed vapours/inert gases from the vacuum system and liquid organic purge from the condensation section are recovered as fuel in a furnace, where thermal oil for the process is heated
There are many advantages of using a plug flow or continuous flow reactor over a traditional batch reactor. Selecting the correct type of flow reactor for the chemistry and application is key. Whatever the reactor type there are some fundamental advantages of continuous flow reactors.
- Efficient Residence time control – this is a direct function of reactor volume and flow rate.
- Efficient Temperature Control – high surface area to volume ration promotes efficient heat transfer
- Efficient mixing – if under laminar flow conditions mixing is reproducible.
- Limited batch-to-batch variation – the whole reaction sees the same reaction conditions.
- No back mixing
- Direct scalability – the same reactor can be used to produce a range of quantities
- Energy efficiency – the continuous nature avoids stopping and starting as in batch reactions.
Key Features of Our Polymer Devolatilization Equipment:
- Very low residue content (residual VOC) levels
- Prevention of damage to product due to avoidance of elevated process temperatures and hot spots through efficient heat transfer equipment
- Ideal for sensitive products due to low shear forces in the process
- Lower power consumption due to the absence of heavy rotating equipment
- Reduced mechanical maintenance
- Moderate capital cost due to unique process concept
The key features of POLYTECH HIPS technology are:
- special and unique process and mechanical design of key equipment such as the reactor and devolatilizer;
- really simple process scheme and easy process control;
- flexible technology allowing tailor-made solutions for specific needs, in terms of plant capacity and products range;
- minimum amounts and number of foreign materials introduced in the process;
- very low residual monomer and oligomer content;
- very high rubber phase efficiency (reduced rubber consumption), minimum rubber cross-linking and polymer degradation;
- POLYTECH HIPS technology minimizes the effects of raw materials and chemical impurities on the process and product structural parameters;
- fine-tuned macromolecular structure (rubber particles size and resins molecular weights distribution)
