Abstract: The present invention provides a method of preparing vinyl chloride polymer having excellent processability and high bulk density by the separate stepwise additions of vinyl chloride monomer during suspension polymerization.

Abstract: Disclosed are a calibration device, a calibration system and a calibration method. The calibration device includes a camera configured to capture image information, a laser sensor configured to capture image information, a laser sensor configured to detect distance information, and a calibration module configured to perform a calibration of the camera and the laser sensor by obtaining a relation between the image information and the distance information, wherein the calibration module includes a plane member disposed to intersect a scanning surface of the laser sensor such that an intersection line is generated, and disposed within a capturing range by the camera so as to be captured by the camera, and a controller configured to perform coordinate conversions with respect to the image information and the distance information based on a ratio between one side of the plane member and the intersection line, and based on a plane member image included in the image information.

Abstract: The present invention relates to a method of preparing a vinyl chloride polymer, and more precisely, a method of preparing a vinyl chloride polymer having excellent processability by raising a final polymerization temperature up to 5˜20° C. from an first polymerization temperature.

Abstract: The present invention provides a method of preparing vinyl chloride polymer having excellent processability and high bulk density by the separate stepwise additions of vinyl chloride monomer during suspension polymerization.

Abstract: The present invention relates to a dispersant for manufacturing vinyl chloride resin and a method of manufacturing vinyl chloride resin using the same. More precisely, this invention relates to a dispersant which is prepared by RAFT, harbors a hydrophobic group and one or more hydrophilic groups not containing a hydroxy group, and has a polydispersity index of 1.1-2, and a method of manufacturing vinyl chloride resin using the said dispersant. The dispersant for manufacturing vinyl chloride resin of the present invention and the manufacturing method of the present invention facilitates the preparation of vinyl chloride resin characterized by even size distribution, excellent sphericity and proper particle diameter.