摘要:
Milled, small particle size, solid bicyclo[2.2.1]heptane dicarboxylate salt-containing thermoplastic nucleating additive formulations further comprising at least one anticaking agent for improved haze reduction, improved nucleation performance, and prevention of potential cementation (via agglomeration) of the salt component present therein are provided. Such small particle size dicarboxylate salts provide desirable properties within thermoplastic articles, particularly as nucleating agents, but apparently suffer from certain clarity issues and agglomeration problems (due to the flat and thin plate structures of such compounds and the propensity they exhibit to cohere to each other during storage), making utilization thereof less desirable for certain applications. Thus, an improvement has been provided to permit full benefit of the excellent crystallization temperatures, stiffness, and calcium stearate compatibility such dicarboxylate salts accord within target low haze thermoplastics. Furthermore, unexpected improvements in dusting reduction have been found upon the utilization of such anticaking additives in combination with the aforementioned nucleating salts. Thermoplastic additive compositions and methods of producing thermoplastics with such nucleator/anticaking additive combinations are also contemplated within this invention.
摘要:
Diacetals of sorbitols and xylitols are employed in polyolefins as nucleating agents. Diacetals of sorbitols and xylitol nucleating agents may be provided in granular or powder form from hoppers or mixing equipment into polyolefins during the formation of polymeric compositions and polymeric articles. Flow of diacetals of sorbitols and xylitols is improved by the use of certain silicas, in certain defined weight percentages. Submicron size range silica compounds may provide excellent flow enhancement properties when blended and used with such diacetals.