PU system for manufacturing products out of viscoelastic molded polyurethane foam

POLYSYSTEM 40

Application:

POLYSYSTEM 40 two-component PU-system is designed for manufacturing products out of viscoelastic molded polyurethane foam with further application in medical, automotive and furniture industries.


System description:

POLYSYSTEM 40 Component A is a mixture of simple polyethers, foaming agents and functional additives.
POLYSYSTEM 40 Component B is a special composition based on diphenylmethane diisocyanate (MDI-based Component B).
Typical indicators:
* after the component homogenization.


Foaming parameters (mass ratio of Components A : B = 100 : 44)
Foaming conditions: stirring with a mixer for 8 s at a rotation speed of 2800 min-1. Components' temperature during foaming: (23 ± 2) °C. Foaming characteristics may vary depending on the foaming conditions.


Recommended ratio:


Recommendations for processing:


The key conditions for the qualitative filling of a form with polyurethane foam are: compliance with the accuracy of dosing and temperature conditions of the components' processing regime; sufficient mass of the poured PU-system portion; proper preparation and appropriate temperature of the mold working surface.

POLYSYSTEM 40 PU-system is processed by filling open or closed molds of various sizes and configurations by means of high- or low-pressure machines, or manually.
POLYSYSTEM 40 Component A has a tendency to delaminate during storage. In order to avoid any non-observance of the formulation or getting defective products, the contents of the containers with Component A, prior to their emptying or loading the contents into the container of a filling machine (or processing by manual filling) are carefully homogenized using suitable mixing equipment (barrel stirrer, etc.). It is not recommended to mix Component A only by circulating it in a closed loop, as this often does not let the component achieve the required degree of homogenization. During the processing, Component A, placed in the container of a filling machine, must also be constantly mixed with a standard mixing device.

Before pouring the system into molds, the molds are cleaned and lubricated with anti-adhesive lubricant (based on waxes, oils, silicones, etc.), which ensures easy and quick removal of finished products. Optimal temperature of the mold working surface is (35 - 55) °C. Before processing, the components are thermostated up to (22 - 28) °C. The products' molding time is 5 - 8 minutes (depending on their size and configuration).
Once the molding time is over, the product is removed from the mold and kept for 24 hours in a room with a temperature not lower than 18 °C - to ensure the final curing of polyurethane foam. Technical documentation for the equipment and the process of obtaining finished products are the guidelines for the PU-system processing.


Documentation

TT NPU-001-2019 technical requirements. POLYSYSTEM 40 polyurethane system.


Handling and storage

POLYSYSTEM 40 Component A warranty period of storage is 6 months - when stored in a dry place in a hermetically sealed manufacturer's container at a temperature of (10 – 25) °C.

POLYSYSTEM 40 Component B warranty period of storage is 6 months - when stored in a dry place in a hermetically sealed manufacturer's container at a temperature of (15 – 25) °C. Storing Component B at a lower temperature might cause its partial crystallization. In this case, the material gets quickly and evenly heated at a temperature of 70 – 80 °C to its complete melting; the process excludes any component exposure to the influence of high temperature for more than 24 hours, and ensures careful avoidance of the material getting locally overheated. The heated and completely melted Component B is thoroughly mixed and processed as quickly as possible at a temperature not lower than 20 °C, for the temperature of the start of material crystallization (chilling point) might increase after the heating.

The repeated crystallization of Component B usually requires a higher temperature and/or more time for its complete re-melting, which often leads to a significant deterioration in quality or irreversible damage of material. Storing Component B at a temperature of 50 °C or above can lead to the formation of insoluble solid products and to the increase in the material viscosity. Component B easily reacts with water to form polyurea and release carbon dioxide, which, in turn, can lead to a dangerous increase in pressure in the closed containers with the product. It is necessary to exclude the possibility of the material's contact with water in any form (containers with wet surface, watered solvents, moist air). All barrels with Component B (as well as the empty barrels that used to contain this Component) must only be stored tightly sealed.

The POLYSYSTEM 40 PU-system technical requirements are also the guidelines for the transport, storage, handling and safety of these materials. These documents are updated periodically. Ask manufacturers and/or suppliers for updated versions of relevant documents before using the PU-system. When working with the above-mentioned materials, it is necessary to pay attention to personnel health, to compliance with safety and health regulations, as well as to environment safety.


The information contained in this document is based on our current level of technical knowledge and experience. All information and technical support are provided (orally, in writing or in any other form) without any legal warranty or assurance and are subject to change without notice. Due to the large number of factors that may affect the processing and use of our materials, it is hereby understood that the processing facilities that use our materials, technical information or technical support assume a direct obligation to release us from any liability arising thereof. It is expressly agreed that processing facilities must mandatorily conduct their own testing and assessment of our materials' suitability for specific applications, including an assessment of the applicability of our materials in terms of their compliance with applicable laws, rules and regulations relating to industrial safety, occupational health and environmental protection. Any statement or recommendation that is not contained in this document is not authorized and does not put us under any kind of obligation. No provision of this document should be construed as recommending the use of any product or information in violation of any patent for the material or its use. Appropriately protected rights, including the rights of third parties, as well as existing laws and regulations must be observed by the purchaser of our products at their own responsibility.