Amount of monomer reacted

A PTHF with acetoxy end groups (structure 7.13) is obtained. The monomer is consumed more rapidly than the anhydride, because it is much more basic and much more nucleophilic. The degree of polymerisation of the resulting PTHF is controlled by the ratio between the amount of monomer reacted and the sum of the anhydride and the superacid used in the initiation system (relationship 7.14) [2, 3, 7, 35, 36]. 

The weight distribution, dj, of the total polymeric product may be calculated from the ratio of the amount of Rj produced to.the amount of monomer reacted... 

If the polymerisation heat is consumed for heating of a reaction volume and no heat transfer through the outer wall occurs, there will be a definite relationship between the average temperature T in zone, the initial temperature Tq and amount of monomer reacted in all previous zones including the zone ... 

A constant fraction of the monomer is converted to graft copolymer for the reactions of methyl methacrylate and methyl acrylate with SBS this is independent of the amount of monomer and the amount of initiator. Both homopolymer and graft copolymer are formed and 25 - 30% of the monomeric methyl methacrylate reacts to form the graft copolymer while the remainder forms homopolymer the fraction of graft copolymer is close to 40% for methyl acrylate. This is also true for the reaction of acrylonitrile with polystyryllithium, here the amount of graft copolymer is a little lower, in the range of 15 - 20%. ... 

Nd-based catalyst systems comprise a variety of catalyst components. Therefore, the order of addition of these components to the monomer solution is not trivial. The situation is even more complicated as some or even all of the catalyst components can be prereacted prior to the addition to the monomer solution. In catalyst prereaction which is also referred to as catalyst preformation or catalyst aging the catalyst components are mixed and reacted prior to the addition to the monomer solution. Reaction time, reaction temperature and the presence of small amounts of monomer play decisive roles. Alternatively, the catalyst components are separately added to the monomer solution. In this approach the active catalyst is generated in-situ . 

One of the first thioaldehydes stabilized by an aromatic system and by heteroatoms was 2-ethoxynaphthalene-l-thiocarboxaldehyde (2), which was isolated as a trimer by reacting the corresponding aldehyde with H2S in alcohol under acidic conditions. By heating the trimer, it was possible to distill a small amount of monomer, which, however, polymerized after a few hours at room temperature (37JA1721). 

The monomer conversion using the mixture of styrene and maleic anhydride is much higher than in the other cases. This value does not truly represent monomer conversion but, instead, the amount of monomer not lost during treatment. Thus, both reacted monomers and non-volatilized monomers are present in the reported value. The values obtained with maleic anhydride alone represent a large amount of unreacted maleic anhydride, as indicated by the amount extracted and the acid value of the polymer after extraction. In any event, the recovery with styrene-maleic anhydride is considerably higher than in all the other cases. 

Biological degradation of the monomer by means of adding a peroxide-generating enzyme has been shown to reduce the amount of monomer in a latex, as the latter reacts with the radicals originating from the peroxides. This process runs at ambient temperatures, but generally takes days to weeks to reduce the amount of monomer to an acceptable level [6]. 

The dependence of the risk parameters on process variables such as the concentrations of monomer, polymer, initiator or catalyst, solvent, water and particle size (in emulsion) and MWD are of paramount importance to establish the safe operation regions of polymerization reactors, and furthermore to develop optimal control strategies imder safe conditions. The maximum pressure, Pmax> and maximum temperature, Tmax achieved during the runaway depends on the process conditions (e.g., the higher the amount of monomer in the reactor and the process temperature, the higher Pmax and Tmax)- Also important is the rate at which the runaway reaches the maximum pressures and temperatures. This rate will provide an indication of the time that the operator/control system of the plant has to react in order to keep the polymerization imder safe conditions. 

In this case, at time , by removing the unit volume of PMPh-/3=l, the amount of monomer is equal to [Mj ]. At time T > r we obtained < 1, and the amount of monomer in a unit volume is equal to Via time dr an amount d[MJ of monomer will be reacted... 

Fig. 6. Relationship between the ratio of reacted amounts of monomers and the composition of PPO-PEO block copol5nner.

Their data were used to calculate the specific reaction rate constant of the oligomer with molybdate by assuming that the time required to reach maximum color was when 99% had reacted and by taking into account the amount of monomer originally present. It is assumed that at any one time the oligomer molecules are all about the same size, since otherwise spontaneous particle growth... 

Structure and Nomenclature The principal method of polymerizing monomers by the chain kinetic scheme involves the opening of double bonds to form a linear molecule. In a reacting mixture, monomer, fully reacted polymer, and only a small amount of rapidly reacting species are present. Once the polymer terminates, it is dead and cannot react further by the synthesis scheme outlined previously. 

The difficulty concerning the initiation on an industrial scale is that the actual initiation of the polymerization must be recognized before a great amount of monomer is added to the reactor. This can be realized either by chemical in-line analysis, or by a heat balance on the industrial reactor [43]. If the initiation fails and the feed is continued, it may lead to an accumulation of monomer that could react spontaneously in an uncontrolled way. Thus the process becomes a batch reaction, for which the reactor is not designed. 

Consider a batch consisting of a total of M moles of monomer (M = My + M2). At time /, the monomer has a composition /y. In the time interval dt, dM moles of monomer polymerize to form copolymer with a composition Fy. Therefore, at time t + dt, there are (M dM) moles of monomer left whose composition has been changed to (fy — dfi). Writing a material balance on monomer 1 gives that the initial amount of monomer either remains or is reacted (dMy) ... 

The product from emulsion polymerization reactors usually contains a small amount of non-reacted monomers, along with volatile impurities from many sources. Such impurities may include a range of solvents originating from various raw materials, dimers and co-dimers either present in monomers or formed during the polymerization, alcohols from hydrolysis of vinyl esters, products formed from... 

If one reacts butyl lithium (BuLi) with a small amount of monomer, a seed of living polymer is produced. 

In the presence of any substantial amount of oxygen this reaction is extremely rapid, but the terminal peroxy radical formed reacts slowly with monomer and has a relatively rapid termination rate. 

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