The rheology research in Japan is still young in its history. The interest in rheology, however, has been rapidly promoted among scientists and technologists of this country in these ten years. The rheology symposium was first organized in 1951 as a part of the annual colloid symposium of the Chemical Society of Japan. Since 1952 the rheology symposium has been organized as an independent one every year (excepting 1954) under the joint auspices of the Chemical Society of Japan, the Physical Society of Japan, Highpolymer Society and the Japan Society for Testing Materials. Every annual symposium was attended by participants from all parts of the country, the number of which has increased from about 150 to 300 during ten years period. It may therefore be considered that the trend of the rheology research of this country is reflected in the history of this annual symposium.
In order to have a general scope of its history, a statistical analysis is made for the papers contributed to the symposia, the result of which is shown in Table 1, 2 and 3. Table 1 is a list of symposia during these ten years, where the number of contributed papers and the classification of contributors according to institutions to which they belong are indicated. Table 2 and 3 show the classification of research subjects from the viewpoint of rheological materials and from that of rheological phenomena, respectively. The former table indicates that the number of researchers interested in such materials as fiber, plastic and rubber is relatively large, while that for such materials as foodstuff, paint and asphalt is small. This may be pointed out as a characteristic feature of the rheology research of this country. The latter table indicates, however, that the researcher's interests in rheological phenomena are more evenly distributed. This may be due to the existence of theoretical works of a relatively large number.
For the sake of comparison, the interests of the members of the British Society of Rheology listed in ‘List of Members’ October, 1959 are classified in the same way as above, the result is shown in Table 4 and 5. As the material used for these tables and that for former tables (2, 3) are different in nature, the comparison between two cases cannot be made reasonably. Nevertheless, some idea for the characteristic features of research in Japan and Great Britain may be obtained from the survey of these tables.
It is especially desired that the rheology research in Japan will be developed also in such areas like biological materials in the next ten years.

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Rheological studies on highpolymers have made great progress in recent years, and have obtained a number of excellent results which are being systematized into well refined theories. For instance, the development of the methods for the measurement of relaxation spectra covering a very wide range of time-scale and the establishment of the meaning of spectra are among the outstanding fruits of recent rheological studies on highpolymers, and, so far as the amorphous substances are concerned, the relaxation spectrum supplements a new description of property which is characteristic to the material. However, we are now in the position to pay attention to the fact that the recent development of the knowledge on the fine structure of materials have little been introduced into the analysis of the mechanical properties of the materials. As a matter of fact, in the rheological studies hitherto, the states of materials are only very roughly classified into a few simple types, such as amorphous, crystalline, and mixed system of amorphous and crystalline phases. This formal simplicity has helped thus far the development of rheological studies, but it is now desired to treat the problems from the more real standpoint of view.
This we pointed out five years ago at the 5th Symposium of Rheology of Japan (November, 1956), and showed as examples some of the results of “photo-viscoelastic” studies which had been commenced by us earlier. In these studies the change in birefringence could be measured at the same time as stress and strain. Recently Utsumi supplemented a work with the thin films of slightly vulcanized rubber, which are thought to behave in comformity to the theory of rubber elasticity. According to the theory, it is expected that the birefringence decreases with time in proportion to the relaxation of stress. This is true only in the case of smaller extension, for the theory does not hold in the case of higher extension, as can be seen in Fig. 1. In the latter case the stress relaxes as rapidly as ever, but the change in birefringence becomes smaller, and finally, at a greater extension, it increases with time contrary to the stress. Therefore, the change in birefringence gives us information about the threshold elongation, over which the deformation begins to deviate from the rubber elasticity. The increase in the birefringence with time will mean the spontaneous orientation or crystallization of the stretched rubber molecules, which results in the spontaneous contract of the cross-sectional area of the material. This is one of the origins of stress relaxation. Therefore, the relaxation at a higher extention is not purely caused by the entropy change. In fact, the film which is stretched to a high extent shows the sharp spots due to the crystallites in the x-ray diffraction pattern, as shown in Photo. 1. But for the simultaneous measurements of birefringence, which gives a measure of inner structure of material with respect to the molecular orientation, the stress relaxation at the higher extension could not be distinguished from the usual rubber elastic phenomenon.
The importance of incorporation of structure researches in the rheological studies has remarkably increased, since the characteristic behaviors of polymer molecules at their crystallization have been elucidated recently by many research workers. Without the knowledge of fine structure the mechanical properties of polymers such as polyolefins, polyamides and polyesters which have great importance in practice could not be explained.
For instance, the polyethylene filament or film which has not been subjected to the cold-drawing shows a very small value of Young's modulus such as 10¹⁰ dynes·cm^-2, which is the value as small as about one hundredth of that characteristic to the crystallites of the usual concept heretofore available.

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The stiffening of elastomers by filler loading is both a surface and a volume effects. As expressed in a formula by Guth and Smallwood, volume effect means the increase of the strain energy, and is due to the stress disturbance in the matrix around filler particles. Therefore, a more general formula applicable also to reinforced hard polymers will be derived, provided that the volume dilation term is not omitted when the equation of equilibrium in terms of displacements is solved: The result of our analysis is presented in the text.
The analysis of surface effect has been developed by many investigators. Among them, Furukawa and A.M. Bueche modified the stress equation of rubber elasticity based on the kinetic theory by introducing the term accounting for additional network chains resulting from the adhesion of polymer molecules on filler surfaces. Recently, a more precise equation was derived by Sato which included, besides a surface and a volume effects, a cavity effect due to incomplete wetting.
There were many reports which suggested that the bond between rubber and active fillers, such as fine silica and carbon black, was so strong as to be considered chemical in nature. However, a variety of data suggesting the existence of weak bonds something thixotropic in nature were also presented.
F. Bueche proposed a molecular theory for the softening of filled rubber which was caused by prestretching. He indicated that short chains fastened their both ends to filler particles should be easily broken by a slight stretching owing to stress concentration, even when the adhesion was strong. He also showed that the recovery of hardness in prestretched, filled SBR was a rate process having an activation energy of about 22kcal/mole. Such a method of analysis is of promise for studying the rubber-filler interactions.
Some important reports on viscoelastic behaviour of filler-rubber systems are reviewed. Thomas et al. have accomplished their studies on the rupture of rubber in view of the energy balance theory, which was began about ten years ago. They found that the tearing energy was the order of 10⁶ erg cm^-2, considerably in excess of surface energy, and indicated that the irreversible dissipation of energy due to viscous or viscoelastic deformation around the tip of tearing front governed the rupture process. They also studied the dependence of rupture energy on rate, temperature, and filler loading, and observed a remarkable increase of the tearing energy over a range of rates and temperatures for SBR vulcanizate reinforced with F T black: Since this filler has a limited reinforcing ability, an enormous energy dissipation at the transition region will be ascribed to the increase of internal friction by filler.

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It is known that when barium-ferrite powder mixed in rubber is charged in a strong magnetic field, it turns into an elastic permanent magnet. But, when ferrite powder is mixed at random, the magnet obtained gives the same properties of any directions (isotropy). On the other hand, when the ferrite grains are arranged to line up along a given direction within the base rubber, an anisotropic rubber magnet which has particularly an excellent magnetic property can be obtained. Beside the widely adopted method of moulding in magnetic field for isomering of sintered magnet, we tried the rolling method on a calendering machine in an attempt to make the crystallizing axis of ferrite grains lie along a given direction inside the rubber, and obtained quite a good result. That is, the unvulcanized rubber stock into which the ferrite powder is mixed is thinned down on a calender-roll through repeated operations. The test piece thus processed showed the maximum energy product, (B.H.)_max≈0.7×10⁶
Although it may also differ according to the shape and variation of grain size of ferrite, the muximum mixable quantity into the rubber greatly differs according to kinds of base rubber. Natural rubber, butyl rubber, etc. are considered suitable for high loaded compounds, while silicon rubber, polysulfide rubber, etc. are not suitable for binders. We also made experiment on the relationship between properties magnetic and rubberic, and the mixing quantities of ferrite powder.

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Viscoelastic properties of several kinds of bentonite pastes were measured under constant shearing stresses by the use of a cone-and-plate type viscometer. It was found that the paste had two threshold values of shearing stress which were named“lower limit”and“upper limit, ” and that the viscoelastic behavior appeared markedly between these two limits. Below the lower limit of stress no deformation was observed. The bentonite in swelling liquids showed the viscoelastic behavior is different from that in non-swelling liquids. The upper limit was assumed to be a value above which local breakdown of the structure of paste occurs. This upper limit was compared with the critical value obtained from a uniaxial compression test and that from a direct shear test used in soil mechanics. The upper limit σ₂^* was found to be related to the shear fracture, and was experssed experimentally by the following equation:
σ₂^*=A·exp (k·c)
where c is the concentration of bentonite and A and k are constants. σ₂^* takes a higher value in swelling liquids than in non-swelling liquids.

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By the use of the direct shear test, the internal friction was determined. The shearing stress increases pulsatively with the increase of shearing displacement and saturate gradually. This phenomenon is connected with the inordinary flow of powdered bed in the shear box. In general, the vertical height of packed powder gradually decrease with the increase of shearing displacement, while the powder composed of cubical particles, such as sugar, expands its volume during shearing. This is a kind of dilatancy. The internal friction of powdered foodstuff was found to be ranging from 0.23 to 0.70.
It was established that when a powder is mechanically tapped, the relation between the strain γ and the number of times of tapping N is represented by the equation, γ=abN/(1+bN), where a and b are the material constants of infinite compressibility and flowbility respectively. The value of a was ranging from 0.9×10^-1 to 3.3×10^-1 and the b value from 2.3×10^-2 to 17.5×10^-2.
When the bed of powder is compressed, strain γ for stress σ and loading time t are connected by Nutting's equation, γ=∅^-1σβt^κ, where ∅, β and κ are constants. The logarithmic ∅ was ranging from 4.0 to 16.0, the β from 0.3 to 2.0 and κ from 0.2 to 0.35 respectively. Thus the loosing bed of powder has the flow property of intermediate material.
The a value is proportional to β and logarithmic ∅, and decreased with the increase of the internal friction of powder. In the case of powdered bed, ∅ value called“firmness”by G. W. Scott Blair is a material constant that is proportional to internal friction of powder.

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In the previous papers some flow properties of several clay suspensions were measured, using a coaxial cylindrical viscometer, and viscosity coefficients, yield properties, thixotropic levels, and the concentration dependence of these properties were also determined. In this report, the relation between these fundamental properties and the casting characteristics of these suspensions are investigated. Results obtained are as follows:
(1) the moderate viscosity fit for the forming in the casting mold ranges between 1500 and 3000cp,
(2) the moderate yield values possessed by the casting bodies are 100 dyne/cm²,
(3) the thixotropic levels suitable to perform the solid casting are 400cp.

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By the use of the coaxial cylinder rheometer, the viscoelastic properties of reconstituted skim milk and renneted milk gel have been measured under various temperatures, concentration of skim milk and rennet.
The aqueous solutions of skim milk in the concentration range from 35 to 50 weight percent show a remarkable non-Newtonian behavior over a frequency range between 10^-4 and 10^-1cps. The viscosity at the zero frequency, therefore, could not be measured. According to Ferry's reduction method, however, the master curves for the reduced viscosity and rigidity have been obtained for both the temperature and concentration relationships. The activation energy calculated from the linear relation between log a_T and 1/T is 93kcal/mol.
As skim milk coagulates by adding commercial rennet, the viscoelasticity of renneted milk gel increases at the lapse of setting time. The velocity of gelation varies with the concentration of skim milk, the temperature of setting and the concentration of added rennet. The velocity constant K of gelation was defined as the reciprocal of the setting time when the value of viscosity and rigidity reaches the half value of maximum respectively. It has been found that log K increases linearly with temperature above about 25°C, below which the enzyme action of rennet is inactive. The activation energy for gelation is about 59kcal/mol.
The relation between K and the concentration of rennet c, is represented by an equation K=K_∞(1-e^-kc), where K_∞ is the maximum velocity constant and k is a constant. The gelation of milk seems to be caused primarily by the adsorption of rennet to casein molecules which is followed by the denaturation.

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In the previous paper of this series, the tensile stress relaxation behavior of polyvinyl alcohol derivatives was investigated in order to clarify the validity of time-temperature superposition for the crystalline polymer systems ranging from semi- to quasi- crystalline.
It was concluded that the hypothesis of time-temperature superposition should be invalid over the glass-transition and the leathery (rubbery) regions in contrast to the amorphous polymers, even if the hypothesis was valid within the respective regions, separetely.
In this paper the tensile stress relaxation behavior of several types of polyethylene having different degree of branching has been investigated at various temperatures from -30°C to near melting point within the limit of linear viscoelasticity and the validity of time-temperature superposition for the highly crystalline system having degree of crystallinity more than 50% has been examined.
As is well known, the degree of crystallinity of polyethylene changes with temperature even in a temperature range considerably lower than the melting point, and this necessitates some corrections on the temperature dependence of relaxation modulus. Unless otherwise, the procedure of time-temperature superposition can not be carried out, actually.
The correction with the change of degree of crystallinity, which was estimated from specific volume-temperature curve, was tried by using a method proposed by Takemura, however the correction failed in the range near melting point.
After the correction except for the higher temperature range as above, the master relaxation curve was composed within temperature range from -30 to 100°C for linear polyethylenes and to 90°C for branched ones, and the temperature dependence of shift factor a_T(T) and the apparent activation energy of relaxation process ΔH_a were evaluated.
The apparent activation energy ranged within reasonable values when compared with literatured ones, showing a broad maximum at about 10°C, of which maximum value increased with increasing the degree of branching. The temperature dependnce of shift factor a_T(T) gave a straight line when plotted in T-T₀/log a_T vs. T for the branched polymer, whereas two segments of straight line jointed at about 40°C for the linear polymer.
This anomaly for the linear polymer should be interpreted in terms of more prominent existence of disordering transition of crystalline phase observed on the temperature dispersion of dynamic modulus than the branched polymer, and suggests the invalidity of time-temperature superposition over the glass transition and the leathery regions.

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Structure of fibers of isotactic polypropylene (PP) was investigated by the effects of isotacticity of raw materials and extraction with several solvents upon temperature characteristics of dynamic modulus, E', and dynamic loss, E".
E' and E" of PP fibers were measured at 100c/s using the direct reading dynamic viscoelastometer. The specimens were prepared by drawing the quenched film to the seven times of the original length at 95°C. Two remarkable absorptions were observed for all specimens: the α_a absorption located at about 20°C ascribed to the amorphous region and the α_c absorption located at about 100°C ascribed to the crystalline region. The intensities and temperatures of these absorption maxima are shown in Table 2.
In the extreme case, where the amorphous region (A) and the crystalline region (C) have the respective characteristic relaxation mechanisms and are combined in parallel with respect to transmission of applied stress, there consists the fundamental relation that two absorptions appear at temperatures characteristic of the regions of A and C and their intensities are proportional to the volume fraction of each corresponding phase. On the contrary, only one absorption appears in the A-C series model. The relations of Fig. 1 are qualitatively interpreted by the A-C parallel model. In this case, it is essential for appearance of the α_c absorption that the fibrils formed with continuous crystalline phase, scarcely interrupted by the amorphous region in the course of stress-transmission, exists in the structure of fiber, while some defects of crystal lattice may be contained within the fibrils. On the other hand, the amorphous region causing the α_a absorption will exist in the interfibrillar space and also perhaps between crystallites as seen in the fringed micell model heretofore accepted.
Fig. 4 shows temperature characteristics of E'and E" for specimens separately extracted with ether, acetone or n-hexane on the seven times drawn PP fibers (the sample D in Table 1). According to Fig. 4, the intensity of the α_a absorption decreases and the value of E' increases systematically with proceeding of extraction. From these results, it is clear that selective extraction of the amorphous region took place. The invariance of locations of the α_a absorptions with extraction shows the fact that the state of aggregation of unextractable amorphous chains, e.g. due to anchoring a part of the chains in the crystal lattice of fibril, are in the same state as in that of the extractable amorphous chains consisting chiefly of atactic structure.
The E' vs. temperature curves scattered in Fig. 4 meet together in Fig. 5 at temperatures above that of the α_a absorption, when E' and E" of the extracted specimens are calculated with the use of the same cross sectional area as that of the original specimen. This fact could be easily understood, if the region causing the α_a absorption combines in parallel with fibrils causing the α_c absorption with regard to stress-transmission, as illustrated in Fig. 6 schematically. It is difficult to consider that the regions capable of the micro-Brownian movement and causing the α_a absorption are contained within the continuous crystalline phase of fibrils. From these, the separate existence of the continuous crystalline phase, or fibril, are reasonably understood, although some defects may exist within it.
In the structure of fibers, there will also be contained such a region as expressed by the fringed micell model as an intermediate structure besides the above mentioned continuous crystalline fibrils and the isolated amorphous phase.

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There are three difficult points in the studies on the filler reinforcement: (1) the formulation concerned with the internal deformation which must be distinct from the external one, (2) the quantitative representation of the boundary state between the filler and the rubbery medium, which is not easy of the scarcity of experimental information, (3) the formulation of the cavitation caused by elongation which is observed only in filler-reinforced vulcanized rubber.
As have already been treated in our several foregoing papers, the above mentioned difficulties may be solved as follows: the actual adhesion state is approximated by a mixed system comprising both the idealized state of perfect adhesion and the idealized state of perfect non-adhesion; a ratio of the former to the latter is (1-ζ):ζ, where ζ denotes a certain parameter characteristic of the actual adhesion state in question.
By means of this method the internal mechanism of the filler reinforcement may be understood in all the aspects, especially it is made clear that the reinforcement consists of three effects: the volume effect, the surface effect and the cavitation effect.
Although two parameters K₀ (that is g_f^(m)/(g_rd), which is a ratio of the surface density to the volume density)and (1-ζ)in this theory have been hitherto determined only by the mechanical experiment, we will compare in the present study the two pairs of parameters, the parameters which are determined from the mechanical data and the ones which are determined from optical data.
The filled specimens containing various concentrations of basic magnesium carbonate as filler; X=0, 0.084, 0.168, 0.252, 0.336 and 0.42 have been examined here.
From the analysis of both experimental data by means of this theory, we have obtained the common value K₀=2.3, and made clear that the degree of adhesion (1-ζ) tends towards the saturate value, already at the second elongation, in the mechanical experiment, and that the strain birefringence is independent of the repeating times and filler concentration X.
Since the isochromatic lines for the specimens having higher concentration, such as X=0.336, 0.42, are not clear and moreover the transparency of the above specimens are bad, the optical data cannot be analyzed in the present study. We are going to perfrom a more accurate study before long by the use of more transparent specimens.
This theory has been found to be comparatively satisfactory from the viewpoint also of the data of the above experiments.

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Two sorts of dielectic absorption coming from the amorphous part are observed in each of the usual solid linear high polymers. The absorption of the high temperature (low frequency) side is called the α_a-absorption and that of the low temperature (high frequency) side the β_a-absorption.
The shapes of the α_a- and β_a-absorptions are discussed both in experimental and theoretical ways with respect to the dependences of the width and the asymmetry of the absorption curves upon the degree of crystallinity and the chemical structure. Cole-Cole's parameter β and the parameter of the sech-law α are adopted in this paper for representing the characteristic features of the shape of the dielectric absorption curve semi-quantitatively. The shape of the α_a-absorption is discussed at much higher temperatures than T_g and the shape of the β_a-absorption at much lower temperatures than T_g, because the shape of the absorption curve scarecely changes with temperature at these respective temperature ranges.
The observed results are as follows: (α.1) Cole-Cole's parameter β for the α_a-absorption curve of the typical amorphous polymer takes the value of 0.7∼0.8, where β becomes a little smaller with the increase of the steric effect, at least for the polymers which have resemble chemical structures. The β of the polymer which seems to lie between the amorphous and the crystalline polymer (such as PVC and PAN) takes the value of 0.5∼0.6. The value of β decreases with the increase of the degree of crystallinity in the typical crystalline polymer and tends to the value of 0.2∼0.3. (α.2) The α_a-absorption curve shows a little asymmetrical shape if it is plotted in logarithm of the frequency scale. The higher frequency side of the absorption curve is a little gentler than the lower frequency side for the amorphous polymer. With the increase of the degree of crystallinity, the α_a-absorption curve becomes symmetric and, finally, the lower frequency side becomes gentler. (β.1) The β of the β_a-absorption curve takes the value of 0.2∼ 0.4 irrespectively with the degree of crystallinity and with the chemical structure. (β.2) The shape of the β_a-absorption is relatively symmetrical excepting the cases of aromatic polyesters.
The theoretical expressions of the shapes of the α_a-and β_a-absorptions are derived. The calculation is made on the basis of the following mechanisms; that is, the α_a-absorption is due to the segmental micro-Brownian motions of the main chains in the amorphous part and the β_a-absorption is due to the local motions of the main chains in the amorphous part such as the local distortions of the chains in the frozen state. The agreements between the theory and the observations are satisfactory.

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Many studies on the breaking behaviour of high polymer has been done due to its large practical meaning. But the discussion concerning the internal structure is very little due its complexity. Although, the fringe micellar structure is not accepted for all polymers at present, it is proper to think of it for the internal structure of the fiber. According to this structure, there is a wide distribution of lateral order from perfectly ordered state in the crystalline region to random state in the amorahous region. The shape of this distribution differs according to the manufacturing process. The fiber possesses a net-work structure if both ends of the chain molecule are caught in the high lateral ordered region. If some proper swelling agent (NaOH so1. for rayon) is applied to such net-work structure, it relaxes and get freed from low lateral ordered region to high lateral ordered region gradually with the increase of the concentration of the solution, and there by the junction point of the net-work structure remains in more high lateral ordered region. The tensile strength of fiber in such condition is controlled mainly by the number of chain molecules caught by the junction point. The distribution of chain length of the chain molecule caught at both ends has much influence. The maximum valus of the number of molecules in the distribution of chain lengths of chain molecule is related to the tensile strength. The amount relating to the maximum value of the chain length of chain molecule caught at both ends in the high lateral ordered region can be determined from the difference of tensile strength when the concentration of the applying swelling agent is changed. The relation between the amount related to the maximum value of chain length in the high region and lateral order can be determined. In case of ordinary viscose rayon or bemberg, a large peak in the distribution occurs at the low lateral ordered region, which shows a discontinuous state of micelle. In case of all-skin type high tenacity rayon, there is no distribution at the low lateral ordered and the distribution in concentrated highly at the right peak region of high lateral ordered region. Fortisan shows a wide distribution and is distributed up to the very high lateral ordered region. The distribution at the low lateral ordered region increases gradually with the decrease of the thickness of skin layer for four types of rayon having different ratio of skin and core. When this behaviour is compared with that of ordinary viscose rayon, discussed before, the core part is related to the low ordered region and the skin part to the high lateral ordered region. In case of all-skin type high tenacity rayon, the chain molecule is quite similar in length and the mechanical properties of it is supposed to be good due to the equal distribution of forces to each molecule. The fatigue behaviour four types of high tenacity rayon has been examined as above. Although there were differences in the fatigue life of the four types of high tenacity rayon, on such large differences of tenacity could be seen in the dry state, but there were clear differences in the swelling tensile behaviour. When the distribution of tensile strength in respect to lateral order is determined, the fiber of short fatigue life shows a large distribution of chain molecule at the low lateral ordered region, and for that of long fatigue life the distribution is large at the high lateral ordered region. In case of repeating extension, it is necessary to distribute the forces to each chain molecule effectively, and in case of low ordered region the distribution is not sufficient, while the distribution is effective in the high region and the concentration of force is avoided.

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The Second Congress on Cohesion and Adhesion was held at the research center of General Motors Co. (G. M.) in Detroit on July 24 and 25 under the sponsorship of G. M. There were about a hundred attendants including P. Debye (Cornell Univ.), H. Mark (Brooklyn Polytech.), M. Bueche (G. E.), Bikerman (MIT), de Bruyne (Aero Research Ltd.), Bowden (Cambridge Univ.), Zisman (Naval Research Lab.) and other prominent researchers. The Congress involved several problems, such as the nature of intermolecular force, statics for adhesives, surface chemistry and adhesion, and rheology of adhesion. Some interesting suggestions concerning experimental method or theoretical treatment were offered and valuable conclusions were drawn, but the problems seemed to be still complicated and were not yet settled so clearly in comparison to other rheological studies. The following is the list of papers read at the Congress.
Dr. L. R. Hafstad, Vice President (G. M.), “Welcoming Remarks”
Prof. P. J. W. Debye (Cornell Univ.), “Interatomic and Intermolecular Forces in Adhesion and Cohesion”
Dr. A. M. Bueche and Dr. J. P. Berry (G. E.), “Ultimate Strength of Polymers”
Prof. J. J. Bikerman (MIT), “Science of Adhesive Joints”
Dr. N. A. de Bruyne (Aero Research), “The Measurement of the Strength of Adhesive and Cohesive Joints”
D. H. Kaelble (Minnesota Mining and Manufacturing Co.), “Theory and Analysis of Peel Adhesion”
Dr. R. N. Fitzwater and J. H. Engel (G. M.), “Adhesion of Surface Coatings as Determined by the Peel Method”
Dr. W. K. Asbeck (U. C. C.), “Forces in Coatings Removal by the Cutting Mechanism”
Prof. D. J. Harvey (G. M.), “The Wetting of Metals by Lead Alloys”
Dr. S. L. Reegen and G. A. lkka (G. M.), “Adhesion of Polyurethanes to Metals”
Dr. W. A. Zisman (Naval Research Laboratories), “Constitutional Effects on Adhesion and Cohesion”
Dr. T. J. Mao and Dr. S. L. Reegen (G. M.), “Adhesion of Some Acrylic Polymers and Copolymers”
Dr. S. B. Newman (National Bureau of Standards), “Microscopical Studies of Failure in Polymers”
Prof. H. F. Mark (Polytechnic Institute of Brooklyn), “Future Trends for Improvement of Cohesive and Adhesive Strength”

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