Abstract: The present disclosure provides a method for preparing multi-component polymers through post-polymerization modification, used to functionalize polysulfonyl imidate polymer including a dispersing polymer reactant, an electrophilic substitution reagent and a catalyst in an organic dispersant; adding acid-binding agent to react at room temperature for 4-48 h; obtaining the precipitate when the reaction finished; washing and drying the obtained precipitate to get the functionalized multi-component polymers. The present disclosure involves a low polymerization temperature, allowing for the reaction to occur at room temperature. Additionally, the conversion rate is high, and the applicable electrophilic substitution monomer reagents have a wide selection. Besides that, the synthesis cost of the reaction is low due to the widespread availability of common chemical reagents such as catalysts, organic dispersants, acid binding agents, and other reaction reagents.

Abstract: A boost power factor correction circuit, a driving circuit for light-emitting diodes and a lighting device are provided. The boost power factor correction circuit includes: a PFC controller; a PFC switch controlled by an output of the PFC controller; and an equivalent variable resistor connected between the PFC switch and the ground. A feedback current input of the PFC controller is connected to a node between the PFC switch and the equivalent variable resistor. The resistance of the equivalent variable resistor is controlled by the output voltage of the PFC circuit. In case that the PFC circuit operates under an mains AC or CCG input, the resistance keeps constantly minimum, and in case that the PFC circuit operates under an ECG input, the resistance increases as the output voltage of the PFC circuit decreases.

Abstract: Various embodiments may relate to an end cap for a lamp tube of an illuminating device, including a mounting ring fixedly mounted to one end of the lamp tube by means of an assembled end, and a cover plate for closing the mounting ring at a free end. The end cap further includes a rotating ring mounted between the mounting ring and the cover plate at the free end, the cover plate rotatably closes the mounting ring by means of the rotating ring. Further various embodiments relate to an illuminating device adopting the end cap.

Abstract: A boost power factor correction circuit, a driving circuit for light-emitting diodes and a lighting device are provided. The boost power factor correction circuit includes: a PFC controller; a PFC switch controlled by an output of the PFC controller; and an equivalent variable resistor connected between the PFC switch and the ground. A feedback current input of the PFC controller is connected to a node between the PFC switch and the equivalent variable resistor. The resistance of the equivalent variable resistor is controlled by the output voltage of the PFC circuit. In case that the PFC circuit operates under an mains AC or CCG input, the resistance keeps constantly minimum, and in case that the PFC circuit operates under an ECG input, the resistance increases as the output voltage of the PFC circuit decreases.

Abstract: Various embodiments may relate to an end cap for a lamp tube of an illuminating device, including a mounting ring fixedly mounted to one end of the lamp tube by means of an assembled end, and a cover plate for closing the mounting ring at a free end. The end cap further includes a rotating ring mounted between the mounting ring and the cover plate at the free end, the cover plate rotatably closes the mounting ring by means of the rotating ring. Further various embodiments relate to an illuminating device adopting the end cap.