Raw material for plastic currently use mostly from plastic waste in order they can sell cheaper than use original plastic seed. The quality of product is not good enough but the price is cheaper than other plastic. Many product sell with bad quality but people only find cheap plastic product don't see the quality of material. The raw material is accumulated from plastic waste material usually from thermoplastic type. This waste then grinding into small piece and then heated, melted and molded into plastic seed material.

Not all plastic waste can be recycled and reprocess into plastic material again, only plastic from thermoplastic source can be recycled again. Other kind of plastic can't be recycled usually they can't melt after heat with certain temperature, they tend to burn and not melt.

The monomer reactivity ratio, r, are the ratio of the rate constant for a radical adding its own monomer to the rate constant for its adding the other monomer. If the r > 1 means the radical M1 prefer to add M2, r < 1 means that it prefers to add M2. In the system styrene (M1) as monomer 1-methyl methacrylate (M2), for example, r1 = 0.52 and r2 = 0.46; each radical adds the other monomer about twice as first its own.

Since the rate constant for initiation and termination do not appear, the composition of the copolymer is independent of overall reaction rate and initiator concentration. The reactivity ratios are unaffected in most cases by the presence of inhibitors, chain transfer agents, or solvents. Even in heterogeneous system they remain unchanged, unless the availability of the monomers is altered by their distribution between phases. A change from a free radical to an ionic mechanism, extensive compilation is given by Young (1975s).

Anionic polymerization was carried out on a commercial scale for many years before the nature of the polymerization was recognized, in the production of the buna-type synthetic rubbers in Germany and Russia by the polymerization of butadiene with sodium or potassium as the catalyst. The first anionic chain reaction to be so identified was the polymerization of methacrylonitrile by sodium in liquid ammonia at -75^oC (Beaman 1948). In modern times, the growth of commercial products of anionic polymerization has been phenomenal (Hsich 1981). Most of these polymerizations are based on the use of organometal catalyst system, which allow unprecedented control over polymer structure.

Mechanism
The conventional method of initiation of ionic chains involves the addition of a negative ion to the monomer, with the opening of a bond or ring and growth at one end:

NH₂^- + CH₂=CHX ──> H₂NCH₂CHX

CH₃O^- + CH₂CH₂=O ──> CH₃OCH₂CH₂O^-

Simultaneous growth from more than one center can be obtained from polyvalent ions such as those derived from:

C [RLi]₄ or N(CH₂CH₂O^-Na⁺)_3-

The more basic the ion, the better it serves to initiate chains. Thus OH^- will not initiate the anionic polymerization of styrene, NH₂^- initiates fairly well, but OCH₂^- is powerful. Similarly, more acid monomers require less basic ions, with the initiation and the stability of the resulting ion.

Initiation can also occur by the transfer of an electron to a monomer of high electron affinity. If D or D^- is an electron donor,

or

D + M ----> D⁺ + M^-
D^- + M ----> D + M^-

Polymer molecular weight can be determined by chemical or physical methods of functional group analysis by measurement of the colligative properties, light scattering, or ultracentrifugation, or by measurement of dilute solution viscosity. All this methods, except the last are, in principle, absoulute: Molecular weight can be calculated without reference to calibration by another method. Dilute of solution viscosity, however, is not a direct measure of molecular weight. Its value lies simplicity of the technique and the fact that it can be related empirically to molecular weight for many systems.

With the exception of some types of end group analysis, all molecular weight method required solubility of the polymer, and all involve extrapolation to infinite dilution or operation in a certain solvent in which ideal solution behavior is attained. The term molar mass is preferred by some authors.

End Group Analysis
Molecular weight determination through group analysis required that the polymer contain a known number of determinable group per molecule. The long chain nature of polymers limits such groups to end groups. Thus the method is called end-group analysis. Since method of end group analysis count the number of molecules in given weight of sample. they yield the number average molecular weight for polydisperse materials. The methods become insensitive at high molecular weight, as the fraction of end groups become too small to be measured with precision. Loss of percision often occurs at molecular weight above 25,000 the limitation being as much o more due to the inability to purify sample and reagents as to lack of sensitivity in the method.

Phenol has been made, over the years, by a variety of process. Many of the companies producing it use it internally and do not sell it on the open market. The principal process in use in the United States is the peroxidation of cumene (isopropyl benzene).

C6H5CH(CH3)2 ----->;; C6H5C(CH3)2 OOH ------>;; C6H5OH + CH3COCH3
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Phenol as Plastic Materials

Plastic industry use chemical intermediate and monomers as plastic raw materials. More detail about these material to produce polymer will write more detail as per groups:

Phenol
Phenol has been made, over the years, by a variety of processes. Many of the companies producing it use it internally and do not sell it on the open market. The principle in use in the United States is the peroxidation of cumene (isopropyl benzene).

C₆H₅CH (CH₃)₂ ----> C₆H₃C (CH₃)₂ OOH -----> C₆H₃OH + CH₃COCH₂

The conversion of cumene to cumene hydrogenperoxide gives a 25 to 50 percent yield per pass. The cumene hydrogenperoxide, which has the dangerous explosive properties of other hydroperoxides, decomposes into acetone and phenol in the presence of sulfuric acid. The by product acetone dominates the acetone market. Phenol can be prepared from toluene, and one small plant in the United States produces it this way. This process is more widely used in Europe.

C₆H₅CH₃ + i.5 O₂ -----> C₆H₅COOH + H₂O

C₆H₅COOH + 0.5 O₂ ------> C₆H₅OH + CO₂