|
Term |
Definition |
|
Cavity Pressure
|
The force that is operating directly on the moulding material at a specific mould location and time during the moulding cycle.
|
|
CD
|
Compact Disk
|
|
CE
|
Cellulose plastics, general
|
|
Cell
|
A small particle or completely enclosed cavity
|
|
Cell (closed)
|
A cell totally enclosed by its walls and hence not interconnecting with other cells. (See Cell and Cell, open).
|
|
Cell (open)
|
A cell not totally enclosed by its walls and hence interconnecting with other cells. (See Cell and Cell, closed).
|
|
Cellular Plastics
|
Plastics containing numerous small cavities (cells), interconnecting or not distributed throughout the mass.
|
|
Celluloid
|
A thermoplastic material made by the intimate blending of cellulose nitrate, with camphor. Alcohol is normally employed as a volatile solvent to assist plasticisation, and its subsequently removed.
|
|
Cellulose
|
A natural high polymeric carbohydrate found in most plants; the main constituent of dried woods, jute, flax, hemp, ramie etc. Cotton is almost pure cellulose; Most commonly occurring carbohydrate; cotton, jute, flax, and hemp are almost pure cellulose
|
|
Cellulose Acetate
|
An acetic acid ester of cellulose. It is obtained by the action, under rigidly controlled conditions, of acetic acid and acetic anhydride on purified cellulose usually obtained from cotton linters. All three available hydroxyl groups in each glucose unit of the cellulose can be acetylated but in the material normally used for plastics it is usual to acetylate fully and then to lower the acetyl value (expressed as acetic acid) to 52-56% by partial hydrolysis. When compounded with suitable plasticisers it gives a tough thermoplastic material.
|
|
Cellulose Acetate Butyrate
|
An ester of cellulose made by the action of a mixture of acetic and butyric acids and their anhydrides on purified cellulose. It is used in the manufacture of plastics which are similar in general properties to cellulose acetate but are tougher and have better moisture resistance and dimensional stability.
|
|
Cellulose Ester
|
A derivative of cellulose in which the free hydroxyl groups attached to the cellulose chain have been replaced wholly or in part by acetic groups, eg nitrate, acetate, or stearate groups. Esterification is effected by the use of a mixture of an acid with its anhydride in the presence of a catalyst, such as sulfuric acid. Mixed esters of cellulose, eg cellulose acetate butyrate, are prepared by the use of mixed acids and mixed anhydrides. Esters and mixed esters, a wide range of which is known, differ in their compatibility with plasticisers, in moulding properties, and in physical characteristics. These esters and mixed esters are used in the manufacture of thermoplastic moulding compositions.
|
|
Cellulose Nitrate (nitrocellulose)
|
A nitric acid ester of cellulose manufactured by the action of a mixture of sulfuric acid and nitric acid on cellulose, such as purified cotton linters. The type of cellulose nitrate used for celluloid manufacture usually contains 10.8-11.1% of nitrogen. The latter figure is the nitrogen content of the dinitrate.
|
|
Cellulose Propionate
|
An ester of cellulose made by the action of propionic acid and its anhydride on purified cellulose. It is used as the basis of a thermoplastic moulding material.
|
|
Cellulose Triacetate
|
A cellulosic material made by reacting purified cellulose with acetic anhydride in the presence of a catalyst. It is used in the form of film and fibres. Films an sheet are cast from clear solutions on to drums with highly polished surfaces. The film, which is of excellent clarity, has high tensile strength, and good heat resistance and dimensional stability. Applications include book jackets, magnetic recording tapes, and various types of packaging. Cellulose triacetate sheet has somewhat similar properties to those of the film and is used to make such articles as safety goggles, map wallets and transparent covers of many kinds.
|
|
Cellulosics
|
Cellulosics go back to the very start of the plastics indusry when John Wesley Hyatt created the first commercial U.S. plastic, cellulose nitrate, in 1868. Several other important members of the cellulosics family, each with its distinct properties, were introduced in the 1900s. Since then, cellulosics have been used to make knobs, appliance housings, handles, toys, packaging, consumer products, and automotive parts, among many other products. Cellulosics are thermoplastic resins manufactured by chemical modification of cellulose [(C6H10O5)n]. Included are: cellophane-regenerated cellulose made by mixing cellulose xanthate [ROCSSH] with a dilute sodium hydroxide [NaOH] solution to form a viscose, then extruding the viscose into an acid bath for regeneration; cellulose acetate-an acetic acid ester [CH3COOC2H5] of cellulose; cellulose acetate butyrate-a mixed ester produced by treating fibrous cellulose with butyric acid [CH3CH2CH2COOH], butyric anhydride [(CH3CH2CH2CO)2O], acetic acid [CH3COOH] and acetic anhydride [(CH3CO)2O] in the presence of sulfuric acid [H2SO4]; cellulose propionate- formed by treating fibrous cellulose with propionic acid [CH3CH2CO2H] and acetic acid and anhydrides in the presence of sulfuric acid; cellulose nitrate-made by treating fibrous cellulosic materials with a mixture of nitric [HNO3] and sulfuric acids.
|
|
Center Gated Mould
|
An injection mould wherein the cavity is filled with resin through an orifice interconnecting the nozzle and the centre of the cavity area. Normally, this orifice is located at the bottom of the cavity when forming items such as containers, tumblers, bowls etc.
|
|
Centrifugal Casting
|
A method of forming thermoplastic resins in which the granular resin is placed in a rotatable container, heated to a molten condition by the transfer of heat through the walls of the container, and rotated so that the centrifugal force induced will force the molten resin to conform to the configuration of the interior surface of the container. Used to fabricate large diameter pipes and similar cylindrical items.
|
|
CF
|
Cresol-formaldehyde
|
|
Chain Length
|
See 'Degree of Polymerisation'
|
Page 9 of 76
[1 2 3 4 5 6 7 8 9 10] Next : Last
|
What does that mean?!