ASTM D1505-18 PDF

Full title and description

Standard Test Method for Density of Plastics by the Density-Gradient Technique — ASTM D1505-18. This test method specifies determination of the density (specific gravity) of solid plastics by observing the level to which a test specimen sinks in a liquid column exhibiting a carefully prepared density gradient; it is intended to provide high-precision density values (design accuracy approximately 0.05%).

Abstract

ASTM D1505-18 (designation D1505 − 18, DOI 10.1520/D1505-18) defines apparatus, calibration (glass floats), temperature control and procedure for producing and reading a density gradient column to measure the density of solid plastics. The method is equivalent to ISO 1183‑2 and is commonly used for films, plaques and molded specimens where accurate density is required. The published 2018 edition is 7 pages long.

General information

• Status: Superseded (original D1505-18 edition published 2018; later revised by ASTM D1505-25).
• Publication date: Approved April 1, 2018 (published April 2018).
• Publisher: ASTM International (American Society for Testing and Materials).
• ICS / categories: 83.080.01 — Plastics in general (density and relative density test methods).
• Edition / version: D1505-18 (designation D1505 − 18).
• Number of pages: 7 pages.

Scope

This test method covers determination of the density of solid plastics by the density‑gradient technique: a specimen is introduced into a liquid column that has a continuous or stepwise density gradient and the level at which the specimen floats is compared to calibrated glass floats or standards of known density. The method states SI units as standard and notes equivalence with ISO 1183‑2. It is intended for films, plaques, molded and machined specimens where the density of the solid material is required.

Key topics and requirements

• Principle: observation of flotation level in a density‑gradient column compared to calibrated standards (glass floats).
• Apparatus: density‑gradient tube, calibrated glass floats, thermostatted bath or means to maintain 23.0 ± 0.1 °C where specified, and means to prepare reproducible gradient liquids.
• Accuracy and sensitivity: method designed for accuracy better than about 0.05 % when appropriate gradient/tube sensitivity is used; guidance given on tube construction for required sensitivity.
• Calibration and verification: use of calibrated floats and standards; recommendations for construction and marking of gradient tubes to achieve required density resolution.
• Reporting: specimen identification, method version (D1505-18), temperature, calibration details, calculated density (g·cm−3) and uncertainty/precision information.

Typical use and users

Used by materials test laboratories, quality control and R&D teams in polymer and plastics manufacturing (polyethylene, polypropylene, polyolefins, engineering plastics), by standards organizations and by regulatory or procurement bodies that need a reproducible reference density method. Typical applications include raw material verification, process control, batch uniformity checks and specification compliance.

Related standards

ISO 1183‑2 (equivalent method), and related ASTM methods for plastics density and related measurements such as D792 (density and specific gravity by displacement). Other ASTM practices and test methods that reference or work alongside D1505 include procedures for specimen preparation and interlaboratory precision studies. The D1505-18 edition has been superseded by a later D1505 revision (D1505-25).

Keywords

density; density‑gradient; specific gravity; plastics; polyethylene; polypropylene; gradient tube; glass floats; ISO 1183‑2; ASTM D1505.

FAQ

Q: What is this standard?

A: ASTM D1505-18 is the 2018 edition of the Standard Test Method for Density of Plastics by the Density‑Gradient Technique, providing the procedure and requirements to measure density of solid plastics using a density‑gradient column.

Q: What does it cover?

A: It covers apparatus, calibration (glass floats/standards), gradient preparation, test procedure, precision/accuracy guidance and reporting for determining density of solid plastics; it is equivalent to ISO 1183‑2.

Q: Who typically uses it?

A: Test laboratories, polymer R&D and QC teams, materials engineers, purchasing/specification writers and regulatory bodies that require a reproducible, high‑precision density measurement for plastics.

Q: Is it current or superseded?

A: The D1505-18 edition was published in 2018; the D1505 family has a later revision (D1505-25) published in 2025 that supersedes the 2018 edition. Users needing the latest normative text should consult ASTM International for the current active designation.

Q: Is it part of a series?

A: Yes — D1505 is a long‑running ASTM test method with prior and subsequent editions (for example D1505-10, D1505-03) and is referenced by other ASTM standards and specifications for plastics; it is also aligned with international methods (ISO 1183‑2).

Q: What are the key keywords?

A: density, density‑gradient technique, specific gravity, plastics testing, glass floats, gradient tube, polyethylene, polypropylene, ISO 1183‑2.