The flow behavior of phenolic molding compound in the moldflowchannel is much concerned with the material temperature.
Then, about the phenolic molding compound on the market, we used the constant-rate plunger flow tester for the purpose of taking the informations of flow behavior, and tried to observe the outflowing material temperature by changing with nozzle diameter, nozzle length, wall temperature of the nozzle and flow rate of material.
And we compared the observed value with the theoretically calculated material temperature at the nozzle outlet.
Thus under the following conditions, 1) the flow behavior of melting material follows the Ostwald-de Waele (Power law) model (Fig. 7), tw=mγw_n
2) the temperature dependence of the parameter m in the above equation follows Arrhenius' law, m=m^*exp (Ef/R_oT)
We tried to calculate the outflowing material temperature by considering the changge of the parameter mowing to radial temperature distribution in the nozzle, from the simultaneous equations (the energy equation and the kinetic equation) as follows, ρC_pu∂T/∂Z=k [1/r (∂T/∂r) + (∂²T/∂r²)] +μ (∂u/∂r) ²
∂P/∂Z=1∂/r∂r [γμ (∂u/∂r)]
As a result, the agreement between the calculated and the observed outflowing material temperature was confirmed within an error of + 2%. (Fig. 9)
In addition, under the condition of rapid flow in the moldflow channel, frictional heat generation by viscous dissipation was great and could be estimated from the following function of the Eckert number in all our experiments.

T_fL (cal) -To/T_L/T_L (cal) -To/T_Lexp [0.137lnEc.+3.25]

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The curing behavior of phenolic molding compounds was studied under the heating and pressing conditions with the JSR-curelastometer and the phase angle indicator.
In addition, the viscoelastic behavior of the materials was tried to analyze during the curing process by assuming two elements Maxwell-model as the viscoelastic model, and by considering heat transfer through the material from the die. As the results, complex elastic modulus G of the material could be calculated with the following equation (W_o' is the force detected actually with the load-cell), G= (9.09X 10⁴) W_o' and the viscoelastic properties of the material during the molding process could be approximated, with practically sufficient precision, by the simple two elements model. (Fig.11)
And the change of element-parameters (elastic coefficient G, viscosity coefficient n) with time were individually estimated with the following equations.
(t is the molding-time)
G=Gm [1-exp {-k_G (t-t_GO)}]
n=nm [1-exp {-kn (t-tno)}]
As a rule, kn was greater than k_G and the temperature dependence of them was represented witth the following equation. (Fig. 7, Fig. 9, and Fig.10)
k=k*exp (-Ec/R_oT)
Tin the above equation is the average material temperature and could be calculated with the following equation. (a is the mean thermal diffusivity)
T≅T_w-0.811 (Tw-To) exp [- (2.47 X10⁶) αt

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Unsaturated polyester resin has 27 years history in Japan. The total production in 1979 was 200,000 metric tons and third biggest production in thermosetting resins following to Phenolic and Urea resins.
More than 75% of consumption is for FRP, in which market of 1979 35% is residential housing, 25% is marine, 11% is tank & vessel, 8 % is construction and appliances.
Owing to the skyrocketing prices of major raw materials, industries of FRP are compelled to make much more efforts than ever to find the advantages of total cost performance and of typical characteristics against competitive materials.
In these economical and industrial situations for FRP, we describe recent technical progresses and developments on unsaturated polyester resins, molding compounds, molding methods, and applications primarily for FRP.

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In 1940, reacting resorcinol with saturated aliphatic aldehydes, J.B. Niederl and H.J. Vogel obtained high melting crystalline condensation products, to which they assigned a ring structure as “porphyrin”.Then, Niederl and J.S. McCoy (1943) re-examined the famous experiment of M. Koebner, who obtained a linear tri-nuclear compound by reacting p-cresol with p-cresoldialcohol, and they suggested that the Koebner's product is not linear, but cyclic four-nuclear compound. In this review, those works of Niederl and co-workers are abstracted with the opposite opinions of S.R. Finn and G.L. Lewis (1950) and H.M. Foster and D.W. Hein (1961). Finally, the rational synthesis of a “cyclic” tetra-nuclear p-cresol novolak by B.T. Hayes, R. F. Hunter (1958) is described rather minutely.

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The useful test methods, Disk cure test and Rockwell hardness test with a cone indenter at an elevated temperature, have been recently developed for evaluating the moldability and deciding the optimum cure time, respectively. The present article describes the features and availability of them, as compared with the other conventional tests, such as Brabender plastograph, Curelastometry, solvent extraction, and Barcol hardness test at an elevated temperature.

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