Natural rubber pale crepe

Ex. 1. Natural rubber (pale crepe or smoked inbbcr Rayon to neoprene 30 21 39 33 12... 

Natural rubber pale crepe was cured in the presence of 0.59 1.0, 2.0, 3.0, U.O, 10.0 and 20.0 parts dicumyl peroxide per h mdred parts of rubber (p.h.r.) at lU5°C for approximately ko minutes. Poly-cis-1, -butadiene samples were cured with 0.5 1.0, 2.0 and U.O p.h.r. dicumyl peroxide under similar conditions. 

In solid form, the natural rubber is graded according to the content of dirt remaining from the precipitation of latex at the plantation. Eight basic NR types have been traditionally recognized internationally. Only the so-called ribbed smoked sheets and the pale crepes are normally used for adhesives. The predominant grade system, the Standard Malaysian Rubber system, has been used since 1965. 

Oxidation of Natural Rubber (NR) Pale Crepe at 46°C, Accelerated by Ultraviolet (UV) Light... 

Any form of natural rubber which is marketed with the rough surface produced by passing the rubber through a series of mills with grooved rolls travelling at differential speeds. The main types are pale crepe, sole crepe, brown crepe and flat bark crepe. 

An efficient peptising agent for natural rubber it is also used as a bleaching agent in the preparation of pale crepe rubber. 

Raw rubber can be either natural or synthetic. The standard grades of natural rubber are smoked sheets and pale crepe. For high grade products, first grade smoked sheets, namely RMAIX or Pale Crepe, is used. Pale Crepe is practically colourless and is preferred in products where delicate colour, extreme whiteness or transparency... 

Natural Rubbers (NR). The chemical name for NR is polyisoprene, which is a homopolymer of isoprene. It has the cis-1,4 configuration. In addition, the polymer contains small amounts of non-rubber substances, notably fatty acids, proteins, and resinous materials that function as mild accelerators and activators for vulcanization. Raw materials for the production of NR must be derived from trees of the Hevea Brasiliensis species. NR is available in a variety of types and grades, including smoked sheets, air-dried sheets, and pale crepes. 

Pale crepe Light, unsmoked natural rubber —... 

White and pale crepe Coagulated natural rubber latex milled to produce a crepe... 

Natural Rubber. Natural rubber (NR), all cw-1,4-polyisoprene, is available as the natural latex, but the major raw material for PSAs is the recovered solid, or baled gum rubber. The principal types of NR used for PSAs are pale crepe or ribbed smoked sheet, which is less expensive but of darker color. The baled rubber must be masticated to lower its molecular weight before use. 

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