The Experts below are selected from a list of 705 Experts worldwide ranked by ideXlab platform

Jiri Stohandl - One of the best experts on this subject based on the ideXlab platform.

  • The role of Organic Phosphite primary structure in the overall stabilization performance in polypropylene
    Polymer Testing, 2017
    Co-Authors: Jiri Tochacek, Radek Matuska, Petr Polacek, Jiri Stohandl
    Abstract:

    Abstract The role of the primary P 3+ functionality in the Phosphite overall stabilization performance was re-evaluated. Tris(2,4-di-t-Bu-phenyl)Phosphite (P-1) and its oxidation product tris(2,4-di-t-Bu-phenyl)phosphate (P-1 ox ) were tested both alone and in the presence of hindered phenol during processing in polypropylene. Efficiencies were quantified using the processing degradation index (PDI). The position of the traditional multiple extrusion curve was determined by a single parameter, describing the degree of polymer degradation. Its reciprocal allowed calculating formulations relative efficiencies. It was shown that oxidation of P 3+ into P 5+ is responsible for 75 % Phosphite stabilization performance, regardless Phosphite acts alone or in combination with phenol. If P 3+ is completely oxidized, stabilizer still works. For the residual performance, the reactions of 2,4-di-t-Bu-phenyl substituents (secondary structure), are responsible. Besides processing, reactions of P 3+ also contribute to the long-term stability at 150 °C. Once Phosphite is oxidized, the secondary structure does not contribute to the long-term stability at all.

Jiri Tochacek - One of the best experts on this subject based on the ideXlab platform.

  • The role of Organic Phosphite primary structure in the overall stabilization performance in polypropylene
    Polymer Testing, 2017
    Co-Authors: Jiri Tochacek, Radek Matuska, Petr Polacek, Jiri Stohandl
    Abstract:

    Abstract The role of the primary P 3+ functionality in the Phosphite overall stabilization performance was re-evaluated. Tris(2,4-di-t-Bu-phenyl)Phosphite (P-1) and its oxidation product tris(2,4-di-t-Bu-phenyl)phosphate (P-1 ox ) were tested both alone and in the presence of hindered phenol during processing in polypropylene. Efficiencies were quantified using the processing degradation index (PDI). The position of the traditional multiple extrusion curve was determined by a single parameter, describing the degree of polymer degradation. Its reciprocal allowed calculating formulations relative efficiencies. It was shown that oxidation of P 3+ into P 5+ is responsible for 75 % Phosphite stabilization performance, regardless Phosphite acts alone or in combination with phenol. If P 3+ is completely oxidized, stabilizer still works. For the residual performance, the reactions of 2,4-di-t-Bu-phenyl substituents (secondary structure), are responsible. Besides processing, reactions of P 3+ also contribute to the long-term stability at 150 °C. Once Phosphite is oxidized, the secondary structure does not contribute to the long-term stability at all.

Pfaendner Rudolf - One of the best experts on this subject based on the ideXlab platform.

Radek Matuska - One of the best experts on this subject based on the ideXlab platform.

  • The role of Organic Phosphite primary structure in the overall stabilization performance in polypropylene
    Polymer Testing, 2017
    Co-Authors: Jiri Tochacek, Radek Matuska, Petr Polacek, Jiri Stohandl
    Abstract:

    Abstract The role of the primary P 3+ functionality in the Phosphite overall stabilization performance was re-evaluated. Tris(2,4-di-t-Bu-phenyl)Phosphite (P-1) and its oxidation product tris(2,4-di-t-Bu-phenyl)phosphate (P-1 ox ) were tested both alone and in the presence of hindered phenol during processing in polypropylene. Efficiencies were quantified using the processing degradation index (PDI). The position of the traditional multiple extrusion curve was determined by a single parameter, describing the degree of polymer degradation. Its reciprocal allowed calculating formulations relative efficiencies. It was shown that oxidation of P 3+ into P 5+ is responsible for 75 % Phosphite stabilization performance, regardless Phosphite acts alone or in combination with phenol. If P 3+ is completely oxidized, stabilizer still works. For the residual performance, the reactions of 2,4-di-t-Bu-phenyl substituents (secondary structure), are responsible. Besides processing, reactions of P 3+ also contribute to the long-term stability at 150 °C. Once Phosphite is oxidized, the secondary structure does not contribute to the long-term stability at all.

Petr Polacek - One of the best experts on this subject based on the ideXlab platform.

  • The role of Organic Phosphite primary structure in the overall stabilization performance in polypropylene
    Polymer Testing, 2017
    Co-Authors: Jiri Tochacek, Radek Matuska, Petr Polacek, Jiri Stohandl
    Abstract:

    Abstract The role of the primary P 3+ functionality in the Phosphite overall stabilization performance was re-evaluated. Tris(2,4-di-t-Bu-phenyl)Phosphite (P-1) and its oxidation product tris(2,4-di-t-Bu-phenyl)phosphate (P-1 ox ) were tested both alone and in the presence of hindered phenol during processing in polypropylene. Efficiencies were quantified using the processing degradation index (PDI). The position of the traditional multiple extrusion curve was determined by a single parameter, describing the degree of polymer degradation. Its reciprocal allowed calculating formulations relative efficiencies. It was shown that oxidation of P 3+ into P 5+ is responsible for 75 % Phosphite stabilization performance, regardless Phosphite acts alone or in combination with phenol. If P 3+ is completely oxidized, stabilizer still works. For the residual performance, the reactions of 2,4-di-t-Bu-phenyl substituents (secondary structure), are responsible. Besides processing, reactions of P 3+ also contribute to the long-term stability at 150 °C. Once Phosphite is oxidized, the secondary structure does not contribute to the long-term stability at all.