BS 6057-1.2-1990 pdf free.Rubber latices — Specification and coding — Section 1.2 Specification for evaporated, preserved natural rubberlatices.
BS 6057-1.2 Standard gives specifications fornatural rubber latex concentrate which has been concentrated by evaporation. It does not apply tonatural rubber latex concentrates which have beenconcentrated by centrifuging or creaming, or tolatices from natural sources other than Heveabrasiliensis, or to compounded latex or vulcanizedlatex.
This International Standard covers requirementsfor evaporated natural rubber latex concentrates ofthe following types:
NR latex,type HA evaporated: Evaporatedlatex concentrate preserved with ammonia onlyor with ammonia together with other
preservative(s), with an alkalinity of at least 0,60 % (mlm) with respect to the latex.
NR latex,type KHS evaporated: Evaporatedlatex concentrate preserved with potassium
hydroxide and having a nominal total solidscontent of 73 % (m/m).
NR latex, type KLS evaporated: Evaporatedlatex concentrate preserved with potassium
hydroxide and having a nominal total solidscontent of 68 % (m/m).
Normative references The following standards contain provisions which,through reference in this text, constitute provisionsof this International Standard.At the time of publication, the editions indicated were valid.Allstandards are subject to revision, and parties toagreements based on this International Standardare encouraged to investigate the possibility ofapplying the most recent editions of the standards indicated below. Members of IEC and ISO maintainregisters of currently valid International Standards.
ISO35:1989,Natural rubber latex concentrate — Determination of mechanical stability.
ISO 123:1985, Rubber latex-Sampling.
ISO 124:1985,Rubber latices— Determination oftotal solids content.
ISO 125:1990,Natural rubber latex concentrate —Determination of alkalinity.
ISO 126:1989,Natural rubber latex concentrate —Determination of dry rubber content.
ISO 506:1985,Natural rubber latex concentrate —Determination of volatile fatty acid number.
ISO 706:1985,Rubber latex -Determination ofcoagulum content (sieve residue).
ISO 2005:1985,Natural rubber latex concentrate—Determination of sludge content.
ISO 7780:1987, Rubbers and rubber latices ——Determination of manganese content – Sodiumperiodate photometric methods.
ISO 8053:1986, Rubber and latex — Determinationof copper content — Photometric method.
The latex concentrate shall conform to therequirements given in Table 1.
In the case of NR latex concentrate,type HA evaporated, the chemical nature and approximatequantity of any preservative(s) other than ammoniashall be stated. NR latex concentrate, type HA evaporated, shall not contain fixed alkali added atany stage in its production.BS 6057-1.2 pdf download.