Provided is a method of producing a vinyl chloride-based polymer including adding a vinyl chloride monomer and a monomer represented by Chemical Formula 1 to a reactor and performing polymerization, wherein an input amount of the monomer represented by Chemical Formula 1 is 1 to 4 parts by weight based on 100 parts by weight of the vinyl chloride monomer, and the monomer represented by Chemical Formula 1 is continuously added to the reactor.

Provided is a method of producing a vinyl chloride-based polymer including adding a vinyl chloride monomer and a monomer represented by Chemical Formula 1 to a reactor and performing polymerization, wherein an input amount of the monomer represented by Chemical Formula 1 is 1 to 4 parts by weight based on 100 parts by weight of the vinyl chloride monomer, and the monomer represented by Chemical Formula 1 is continuously added to the reactor.

Provided is a method of producing a vinyl chloride-based polymer including adding a vinyl chloride monomer and a monomer represented by Chemical Formula 1 to a reactor and performing polymerization, wherein an input amount of the monomer represented by Chemical Formula 1 is 1 to 4 parts by weight based on 100 parts by weight of the vinyl chloride monomer, and the monomer represented by Chemical Formula 1 is continuously added to the reactor.

A dispersion containing a fluorine-containing polymer and a liquid medium. The fluorine-containing polymer includes a repeating unit derived from a fluorine-containing monomer (a) having a Q value of 2.0 or more and comprising a fluoroalkyl group, and a repeating unit derived from a chloride monomer (b) that is at least one selected from vinyl chloride and vinylidene chloride. Further, the dispersion has a concentration of unreacted chloride monomer (b) of 2.0 ppm or less.

A dispersion containing a fluorine-containing polymer and a liquid medium. The fluorine-containing polymer includes a repeating unit derived from a fluorine-containing monomer (a) having a Q value of 2.0 or more and comprising a fluoroalkyl group, and a repeating unit derived from a chloride monomer (b) that is at least one selected from vinyl chloride and vinylidene chloride. Further, the dispersion has a concentration of unreacted chloride monomer (b) of 2.0 ppm or less.

Provided is a method of producing a vinyl chloride-based polymer composite, which includes: forming particle nuclei by bulk polymerizing vinyl chloride-based monomers; producing a vinyl chloride-based polymer by bulk polymerizing vinyl chloride-based monomers in the presence of the particle nuclei; and producing a vinyl chloride-based polymer composite including the vinyl chloride-based polymer and a cellulose-based compound.

Provided is a method of producing a vinyl chloride-based polymer composite, which includes: forming particle nuclei by bulk polymerizing vinyl chloride-based monomers; producing a vinyl chloride-based polymer by bulk polymerizing vinyl chloride-based monomers in the presence of the particle nuclei; and producing a vinyl chloride-based polymer composite including the vinyl chloride-based polymer and a cellulose-based compound.

A modified vinyl alcohol-based polymer includes a polyoxyalkylene unit, and an organic acid unit bonded to a polyvinyl alcohol chain, the polyoxyalkylene unit includes a moiety represented by the general formula (I), the moiety being bonded to the polyvinyl alcohol chain only via an ether bond and/or a carbon-carbon bond, wherein a ratio of a number of moles of monomer units bonded to the polyoxyalkylene unit to a total number of moles of the monomer units constituting the polyvinyl alcohol chain of the modified vinyl alcohol-based polymer is 0.01 mol % to 5 mol %, and a ratio of a number of moles of the organic acid unit to the total number of moles of the monomer units constituting the polyvinyl alcohol chain of the modified vinyl alcohol-based polymer is 0.1 mol % to 10 mol %.

A modified vinyl alcohol-based polymer includes a polyoxyalkylene unit, and an organic acid unit bonded to a polyvinyl alcohol chain, the polyoxyalkylene unit includes a moiety represented by the general formula (I), the moiety being bonded to the polyvinyl alcohol chain only via an ether bond and/or a carbon-carbon bond, wherein a ratio of a number of moles of monomer units bonded to the polyoxyalkylene unit to a total number of moles of the monomer units constituting the polyvinyl alcohol chain of the modified vinyl alcohol-based polymer is 0.01 mol % to 5 mol %, and a ratio of a number of moles of the organic acid unit to the total number of moles of the monomer units constituting the polyvinyl alcohol chain of the modified vinyl alcohol-based polymer is 0.1 mol % to 10 mol %.

An electrophotographic photosensitive member includes: a conductive support; a charge generation layer disposed on the conductive support, the charge generation layer including a charge generating material and a vinyl copolymer, the vinyl copolymer including a structural unit including a chlorine atom, a structural unit including an acyloxy group, and a structural unit including an aromatic polycarboxylic acid structure, a proportion of the structural unit including a chlorine atom to all the structural units being 80% by mass or more, a proportion of the structural unit including an aromatic polycarboxylic acid structure to all the structural units being 0.5% by mass or more; and a charge transport layer disposed on the charge generation layer, the charge transport layer including a charge transporting material and a binder resin.