The dependence of the peeling strength on the peeling rate is treated in this paper rheologically. First we showed experimentally that the time-temperature superposition principle is applicable to the S-type curve of the peeling strength vs, the rate for the amorphous polymer films (Vinylite) of various plasticizer (DBP) contents above glass transition temperature (T_g). The dependence of the shift factor a_T on the temperature obeyed the W. L. F. equation giving reference temperature T_s considerably lower than T_g+50^°, where T_g is measured dilatometrically. This means that the fractional free volume at T_g is larger than 0.025, in our case showing 0.037. This discrepancy is explained by the theory of Ferry and Stratton on the increase of fractional free volume due to the extension of polymers of Poisson's ratio less than 1/2. The apparent activation energy at T_s evaluated from the dependence of log a_T on temperature, are 46.5-33kcal/mol for samples of plasticizer contents 0-40%, which are reasonable values for the viscous flow of the polymer segments. From these experimental results we conclude that the dependence of the peeling strength on the rate is substantially rheological in character, and that the course of peeling is not governed by the electrostatic mechanism as proposed by Deryagin et al.
Secondly, we derived a theoretical formula relating to the peeling strength to the rate of peeling in adhesive tapes, assuming that the adhesive layer is deformed locally only at the peeling end, and its rhelogical behavior is described by the simple Voigt model. It is also assumed for simplicity that the shape of the bend at the peeling end is regarded as a part of a circle of radius R, which is determined by the peeling force P as R=√E_oI/P, and that the deformation is vertical to the adherend surface. If the peeling proceeds steadily with velocity v, we may represent the initial and proceeding stage after time t of peeling with two circles whose centers are at (O, R) and (vt, R). Then the elongation of the adhesive layer at the origin, y, is given as a function of v, R, and t, with its time derivative, dy/dt, as a function of v, R, and y. Introducing this into Voigt's equation and integrating the equation dW=fdy from f=0 to f=f_b where f_b means the critical surface force, we obtain work of deformation, W_d, at the adhesion break. In the work of deformation, elastic energy W_e must be reserved. Put W_d'=W_d-W_e, then the sum of W_a, work of adhesion, and W_d' equals to the work done by the applied force, that is W_a+W_d'=P(1-cosθ), where θ is peeling angle. Carrying necessary calculation with some reasonable approximations, we obtain the following equation in the case of L-peeling (θ=π/2),
P-C₁P^1/4v+C₂P^1/2v²=W_a,
C₁=2√2h^1/2/3(E_oI)^1/4·(f_b/E)^3/2η,
C₂=2/(E_oI)^1/2(η/E)²f_b,
where E_o is Young's modulus of polymer film which determines the curvature at the peeling end, I, its moment of inertia, h, the thickness of the adhesive layer, η and E, viscosity coefficient and Young's modulus of the adhesive. This equation represents well the S-type curve of logP vs.

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Fibers prepared from mixture of polyvinyl alcohol and polyacrylic acid (PA) were heat-treated and formalized. Resistance of these fibers to water, acid, and alkali was examined with the following results
Resistance of unformalized fibers to water increase with heat-treatment and also with increased amount of PA. Above all, boiling water resistance of fibers containig 25_??_30% PA, subjected to heat-treatment at 220°C, is fairly high and is approximately comparable with resistance of ordinary vinylon. Resistance of formalized fibers to boiling water is good.
Resistance of formalized fibers to hydrochloric acid increases as with content of PA is increased, whereas their resistance to alkali decreases

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加硫反応を速度論的に取扱つた報告は殆どない。純化学的に取扱うには、基礎反応が明かでないため難しいが、加硫による彈性の強化が最も鋭敏で、且測定も比較的簡單である。ここでは彈性とゴムの網目数に関する Flory の関係式と、著者等の実驗結果とを用いてT.T. 單独、MBT及びMBTとDPG混合物と硫黄による加硫の場合、極限の加硫度ν∞、t時間後のそれをν、速度恒数kvとすると次の実驗式が良く合う事が分つた。
dν/dt=kv(ν∞-ν)……(1)
又同硫黄量を用いても促進剤の多い程ν∞が大となる事は、硫黄を多くしたときも同じであるがそれよりも効果が大きい。νの生成に対する硫黄消費量は硫黄單独加硫に比べて、促進剤を用いると少くなり、MBTの場合、加硫ゴム強度と、νの関係から推定した値4)と良く一致する。此の事実はゴムの構造に対する1つの示唆となる。温度の影響はアルレニウスの式に從う。

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アクリル酸ブチル-アクリルニトリル (87/13) 共重合体の未分別物について, 希薄溶液粘度におよぼす, 溶解温度, 溶媒, 温度の依存性を検討し分別物の〔η〕と数平均分子量を浸透圧から決定した.
1) 各種溶媒中の〔η〕の比較-ベンゼン>酢酸エチル>アセトン>トルエン>プロピオン酸ブチル>プロピオンニトリル>ジメチルホルムアミド
2) 沈澱点におけるアセトン溶液に対する非溶媒の容積分率-n-ブタノール>エタノール>n-ヘキサン>メタノール>水
3) これらの共重合体は, 80°C以上の高温で分解するが, ヒドロキノンはこのラジカル分解を阻止する.
4) トルエン溶液の〔η〕の温度依存性から, ポリマー鎖の回転に関する見掛けの活性化エネルギーは, 0.25～0.39Kcal/molである.
5)〔η〕-数平均分子量の関係 (アセトン, 30°C)〔η〕=1.70×10^-5•M_n^0.69

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素ねりしたアクリル酸ブチル-アクリルニトリル (87/13) 共重合体の濃厚溶液粘度を, アセトンおよびトルエン溶液中で, B型粘度計を用いて測定した. 粘度におよぼす, ずり速度, 濃度 (6～24%), 分子量 (2.5×10⁶～0.47×10⁶), 温度 (30～70°C) および溶液の安定性について検討した.
1) ずり速度 (D) の影響 D=1/η_A•Sⁿ
ただし S: ずり応力∝粘度計の目盛
D∝粘度計の回転数
η_A: 見掛けの粘度
n: 非ニユートン流動に関する恒数
2) 濃度 (C) の影響 η′∝exp.K_c•C
ただしη′: 1rpmにおける見掛けの粘度
K_c=2.35×10⁷•M_v+0.15
3) 分子量 (M_v)の影響η′∝M_v^3.4
4) 温度 (T) の影響η′∝exp.1/T
分子量1.08×10⁶～0.47×10⁶で, 10%トルエン溶液の見掛けの流動の活性化エネルギーは, 2.8～3.1kcal/molである.

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Effects of organosulfur compounds (thioethers, thiophosphites, and thiophosphates) and organotin compounds as additives on the thermal decomposition of polypropylene were studied. Organosulfur compounds which have electron-donating substituents to sulfur atoms accelerated the thermal decomposition of polypropylene. Apparent activation energies for the scission of the main chain of polypropylene at 250-280°C in vacuum were about 52 and 35kcal/mol in the absence and presence of additives, respectively. The organosulfur compounds used in this study did not decompose during the thermal treatment, and gave no smell of sulfur compounds and showed no coloration. On the other hand, organotin compounds decomposed during the thermal treatment. It was considered that these compounds formed radicals on heating and accelerated the thermal decomposition of polypropylene.

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The stationary viscoelastic properties of general purpose polystyrene (GPPS) and high impact polystyrene (HIPS) melts were measured by means of a screwless extruder. Since the cone rim pressure was not equal to the atmospheric pressure, some theoretical considerations were necessary to derive an approximate relation for calculating the first normal stress difference from the profile of Weissenberg's pressure and the value of pressure at the cone rim.
Measurements of Weissenberg's pressure were performed in a stationary state which occurred at 7∼10min after the starting of the rotor and continued for about 5min. The first normal stress difference observed for low density polyethylene (M.I.=2.0, 190°C) showed a fairly good agreement with the literature values. The first normal stress difference for GPPS was slightly greater than that for HIPS at the same shear rate.
Some flow properties were measured with an extruder-type rheometer according to both Bagley's and the pressure gradient methods, which gave the same results. The apparent viscosity of HIPS was somewhat greater than that of GPPS at the same shear rate. The rigidity, calculated from the first normal stress difference and the apparent viscosity for HIPS, was considerably higher than that for GPPS at the same shear rate. The correlation between the Weissenberg effect data and the exit pressure data was also examined.

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Graft copolymers of methyl acrylate-g-(2-vinylpyridinium bromide-co-vinylalcohol) were prepared by the reaction of (2-vinylpyridinium bromide-co-vinylalcohol) with methyl acrylate. The flocculating abilities for 5% aqueous kaolin suspension were investigated in the reiation to the structures by measuring the sedimentation rate, the sedimentation volume, and the turbidity. The results obtained are as follows. 1) For every graft copolymer, the optimum copolymer concentration required to flocculate 5% kaolin suspension was 6-50ppm, and under these conditions, the electrophoretic mobility of kaolin was relatively small. 2) Suitable mole fraction of vinylalcohol (F_VA) and that of ionization group (F_I2VP) in copolymer were 0.15 and 0.25 respectively. 3) Flocculating action increased with increase of mole fraction of methyl acrylate (F_MA) in copolymer. 4) Flocculating ability of each copolymer increased with increasing inherent viscosity. 5) Suitable pH values for the flocculating action were in the range of about 2-12. 6) An isoelectric point was found in the vicin ity of pH 4 and optimum flocculating ability was observed in the pH range of 4-10. 7) Copolymers were more effective for typical commercial flocculants such as Sumifioc-FC, PAS-A, and Himoloc Neo 600.

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ポリクロロプレン分別物の流動性を高化式フローテスターを用いて測定し, 毛細管流動特性に及ぼす分子量の効果を検討した.
毛細管流動でのパラメータである押出し圧P, 臨界ずり速度γ_cと重量平均分子量M_wとの間には次のような関係があることが判明した.
logP∝logM, logγ_c∝-logM_w
またダイ•スウェル (D/D₀), 臨界ダイ•スウェル (D/D₀)_cはともに重量平均分子量M_wとの間に正の相関関係があることが認められた.
そしてあるずり速度のもとでダイ•スウェルが1 (ふくらみがなくなる) になるように補外して得られる分子量を臨界分子量と名称することを提案した.

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