The standard specifies the method for determining the pH value of synthetic rubber latex by pH Meter and is applicable to synthetic rubber latex. In the course of the experiment, an analytically pure standard buffer solution with known pH value and distillation water without carbon dioxide or deionized water are used. The preparation method of the standard buffer solution includes standard buffer solution at pH7, pH4 and pH9. Warning Personnel using this standard should be familiar with the regular laboratory operating procedures and develop corresponding safety and health systems to ensure compliance with relevant national regulations.