GB/T 33317-2025 Active National standards

GB/T 33317-2025 Plastics—Determination of hexamethylenetetramine content in phenolic resins—Kjeldahl method, perchloric acid method and hydrochloric acid method

Publish Date: 2025-10-05 Implement Date: 2026-05-01 For services related to genuine standard inquiry, procurement, translation, and other related services in China, please Contact Us

Basic Information

Standard Code: GB/T 33317-2025

Standard Type: National standards

Standard Status: Active

is_force_gb: no

CCS Name: Basic standards and general methods for synthetic resins and plastics

ICS Name: Thermosetting plastics

Publish Date: 2025-10-05

Implement Date: 2026-05-01

Pages: 12 pages

Scope

This document describes three methods for determining the content of hexamethylene tetramine in phenolic resins. These three methods are equivalent.
The Kjeldahl nitrogen determination method is not suitable for phenolic resins containing other nitrogen compounds, nor for resins containing additives that can be oxidized by perchloric acid. The perchloric acid method is not suitable for phenolic resins containing other acidic or alkaline substances, nor for resins containing additives that can be oxidized by perchloric acid. The hydrochloric acid method is not suitable for phenolic resins containing other acidic or alkaline substances.