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1.根据烃类在自动催化氧化过程中的退化支链反应机理;并考虑到过氧化氢物的分解既可生成游离基,也可形成稳定产物;同时还考虑到高分子固体的反应特征,其中终止反应应包括单基终止这一步骤,因之本文作者重新推导在一定温度下聚合物吸氧动力学的方程式如下: lnV_t/V_∞/(1-V_t/V_∞)=(αk_3N_0-yk_5)_t+C其中α=xk_7/(xk_7+(1-x)k_8);x为支化分数,y为单基终止分数。 V_t——在时间为t时聚合物的吸氧量(毫升O_2/克聚合物); V_∞——聚合物在整个吸氧过程中的极限吸氧量(毫升O_2/克聚合物); k_7及k_8——过氧化氢物分解成游离基及生成稳定产物的速度常数; k_5及k_6-——链的单基及双基终止速度常数; k_3——链的增长速度常数。 2.上述方程式可用顺-1,4-聚丁二烯在不同实验温度和不同品种及浓度的添加剂存在时的吸氧数据来验证,因为这些可变因素可以直接影响α及y值的变化,而这些数值反映了自催化过程的有效支链反应程度。对于某一给定条件下所得的数据,若按上述方程式作lnV_t/V_∞/(1-V_t/V_∞)-t图便可得到两个不同的斜率,即反应的前期斜率较低,后期斜率较高,这假设为α及y值在反应前期及后期有所改变。因之,若以斜率较大者作基础,就可求得前后期不同斜率的比值γ_r,并可定义为有效支链反应程度的相对系数,
1. According to the degradation of branched chain reaction mechanism in the process of automatic catalytic oxidation of hydrocarbons, and taking into account the decomposition of hydrogen peroxide can generate free radicals, but also the formation of stable products; also taking into account the reaction characteristics of polymer solids, Among them, the termination of the reaction should include a single base to terminate this step, so the author of the paper to re-derive at a certain temperature polymer oxygen kinetics equation is as follows: lnV_t / V_∞ / (1-V_t / V_∞) = (αk_3N_0-yk_5 ) _t + C where α = xk_7 / (xk_7 + (1-x) k_8); x is the branching fraction and y is the monostatic termination fraction. V_t - oxygen uptake of polymer at time t (ml_O_2 / g polymer); V_∞ - ultimate oxygen uptake (ml_O_2 / g polymer) of the polymer throughout the oxygen uptake; k_7 And k_8 - the decomposition rate of hydrogen peroxide into free radicals and the formation of stable products of the rate constant; k_5 and k_6 --- chain of single and double base constant rate of termination; k_3 - chain growth rate constant. 2. The above equations can be validated by the oxygen uptake data of cis-1,4-polybutadiene in the presence of different experimental temperatures and additives of different species and concentrations because these variables can directly affect the changes of α and γ, These values reflect the degree of efficient branching reactions in the autocatalytic process. For the data obtained under a given condition, two different slopes can be obtained according to the above equation: lnV_t / V_∞ / (1-V_t / V_∞) -t. That is, the slope of the initial stage of the reaction is low, The slope is higher, which assumes that the values of α and y change during the early and late stages of the reaction. Therefore, if the slope is larger, the ratio γ_r of different slopes can be obtained before and after the period, and can be defined as the relative coefficient of the degree of effective branching reaction.