ASTM D1076-14
Standard Specification for Rubber—Concentrated, Ammonia Preserved, Creamed, and Centrifuged Natural Latex

Standard No.
ASTM D1076-14
Release Date
2014
Published By
American Society for Testing and Materials (ASTM)
Status
Replace By
ASTM D1076-15
Latest
ASTM D1076-23
Scope

4.1 This specification denotes limits on the 4 categories of latex as defined in the scope and defines the test methods to use for the specified properties. These test methods may be used for production control or for referee purposes.

1.1 This specification covers requirements for first grade concentrated natural rubber latex (see Table 1) of the following categories:

(A) Dry rubber content by definition and use is the acid coagulable portion of latex after washing and drying.
(B) It is accepted that KOH numbers for boric acid preserved latices will be higher than normal, equivalent to the amount of boric acid in the latex.
(C) Blue or gray color usually denotes iron contamination caused by improper storage in containers.

Category 1—Centrifuged Hevea natural latex preserved with ammonia only or by formaldehyde followed by ammonia.

Category 2—Creamed Hevea natural latex preserved with ammonia only or by formaldehyde followed by ammonia.

Category 3—Centrifuged Hevea natural latex preserved with low ammonia with other necessary preservatives.

Category 4—Centrifuged, or centrifuged and creamed, guayule latex, or other natural rubber latex, containing less than 200 µg total protein per gram dry weight of latex, with ammonia or other hydroxide, with other necessary preservatives and stabilizers.

Category 5—Centrifuged Hevea natural latex treated with aluminum hydroxide or by other means, preserved with ammonia only or by formaldehyde followed by ammonia containing less than 0.5 % non-rubber content.

1.2 This specification is not necessarily applicable to latices prepared or preserved by other methods, and shall not be construed as limiting the desirability or usefulness of other categories of latices. It does apply to natural latex sources other than Hevea brasiliensis but does not apply to compounded latex concentrates.

1.3 The analytical procedures applicable to the specifications are included and appear in the following order: