Industrial cellulose diacetate flakes (commonly used in the manufacture of cellulose acetate, plastics, films, cigarette tow, etc.) have extremely stringent requirements for wood pulp, as its quality directly determines the performance, quality, and processing efficiency of the final product.

The following are detailed requirements for wood pulp selection in industrial cellulose diacetate flakes, which can be divided into two main categories: core indicators and auxiliary requirements:

I. Core Chemical Indicators

This is of paramount importance in wood pulp selection, directly affecting the smooth progress of the acetylation reaction and the quality of the final acetate.

1. High α-cellulose content

Requirement: Typically ≥95%, high-quality pulp can reach 96%-98%.

2. Low hemicellulose content

Requirement: Typically <4%, the lower the better.

3. Extremely low lignin content

Requirement: Typically <0.1%, or even undetectable.

4. Suitable degree of polymerization and molecular weight distribution

Requirement: Degree of polymerization (DP) is typically between 600-1100, depending on the intended use of the final product (e.g., films require high degree of polymerization, some plastics require medium). The molecular weight distribution should be as narrow as possible.

5. Low Ash Content

Requirement: Generally <0.1%, high-quality pulp requires <0.05%.

II. Physical and Appearance Indicators

These indicators affect the operability of production and the appearance of the final product.

1. High Whiteness

Requirement: Generally ≥88%

2. Good Liquid Absorption

Requirement: The pulp board should be loose and porous, capable of quickly and uniformly absorbing activators (glacial acetic acid) and catalysts (sulfuric acid).

In summary, wood pulp used for industrial cellulose diacetate flakes is essentially a high-purity cellulose raw material. The core selection criteria are "high purity, high reactivity, and high uniformity." Any deviation will amplify its negative impact exponentially in subsequent chemical processing and product applications.