For procurement professionals in the chemical and plastics industries, a deep understanding of material specifications is essential for making informed purchasing decisions. Chlorinated Polyethylene (CPE) 135A is a highly versatile additive, but its performance in applications like PVC modification and cable jacketing hinges on its precise technical characteristics. This guide outlines the key specifications that buyers should look for when sourcing CPE 135A from manufacturers and suppliers.

What is CPE 135A?

CPE 135A is a type of chlorinated polyethylene, produced by substituting hydrogen atoms in high-density polyethylene (HDPE) with chlorine atoms. This process results in a polymer with a unique balance of properties, making it an excellent impact modifier and a robust material for various industrial uses. Its CAS number is 63231-66-3.

Critical Specifications for Procurement:

1. Chlorine Content: This is a fundamental parameter that dictates many of CPE's properties. For CPE 135A, the typical chlorine content ranges from 34% to 37%. A higher chlorine content generally enhances flame retardancy and oil resistance but can also affect flexibility. Buyers should confirm this range with their chosen supplier to ensure it aligns with their application requirements.
2. Tensile Strength: This measures the maximum stress a material can withstand before it breaks. For CPE 135A, a tensile strength of typically ≥10.0 MPa is desirable, indicating its ability to withstand pulling forces without failing. This is crucial for applications where structural integrity under stress is important, such as in cable jacketing or robust plastic profiles.
3. Elongation at Break: This refers to the percentage by which a material can stretch before breaking. CPE 135A often shows an elongation of ≥600%, signifying its flexibility and ability to deform significantly without fracturing. This property is vital for applications requiring ductility and impact absorption.
4. Shore Hardness (A): Hardness is a measure of a material's resistance to indentation. For CPE 135A, a Shore Hardness (A) of ≤64% is common, indicating a relatively soft, rubber-like consistency that contributes to its impact modifying capabilities.
5. Heat of Fusion: This parameter, often measured in J/g, indicates the energy required to melt the crystalline structure of the polymer. For CPE 135A, a low heat of fusion (≤2.0 J/g) suggests good processability and a lower tendency to degrade under heat.
6. Volatile Content: This refers to the amount of residual moisture or low molecular weight components in the material. A low volatile content (e.g., ≤0.74%) is important for product stability, processing, and preventing defects like voids or porosity.
7. Residue on Sieve (0.9mm): This test indicates the presence of undispersed particles or impurities. A low residue percentage (e.g., ≤2.0%) from a reputable manufacturer suggests a clean, well-processed product.
8. Mooney Viscosity: This measures the viscosity of the rubber compound. A Mooney viscosity of ≤96 ML(1+4) at 125°C for CPE 135A is typical and provides an indication of its processability and molecular weight.

Making an Informed Purchase Decision

When you are ready to buy Chlorinated Polyethylene, engaging with your potential supplier to thoroughly review these specifications is crucial. Understanding these parameters will help you select the most suitable grade of CPE 135A for your specific application and ensure you are sourcing from a reliable manufacturer in China or globally. High-quality CPE 135A is a valuable investment that can significantly enhance the performance and durability of your finished products.