Rubber-degrading

Tsuchii, A. and Takeda, K., Rubber-degrading enzyme from a bacterial culture, Appl. Bnviron. Microbiol, 56, 269, 1990. 

Cyclic Chain Termination in Oxidized Polypropylene Inhibition of Synthetic Rubber Degradation... 

Rubber degradation in the sealing system occurs when in contact with high pH (basic) and low pH (acidic) fluids in the systems. 

Whereas Redfern [57] has pointed out the advantages of simultaneous thermal analysis techniques (particularly TG-DSC and TG-DTA) over techniques conducted singly, an even more complete thermal profile is provided when a thermal analyser is coupled to some form of gas analyser (MS or FTIR). Mohler and co-workers [51] have reported TG-DSC-MS of the thermal decomposition of the vulcanisation accelerator tetramethyl thiuram disulphide (TMTD) in rubber degradation of TMTD starts at about 155 °C, as evidenced by m/z 76 (CS2) and 44 (radical of the secondary dimethylamine). 

Isayev, A.I. Yashin, V.V. A model for rubber degradation under ultrasonic treatment part I. Acoustic cavitation in viscoelastic solid. Rubber Chem. Technol. 1999, 72, 741. 

Yet in the presence of sulfuric acd, silicone rubber degrades at room temperature (J ). 

The mechanism of the antiozonant protection has been the matter of studies and discussions for a long time [3,4,18,21,31] and it is still an area of active research. Due to the diversity of the deteriogens and reactive products of rubber degradation involved in ozone ageing, more concerted protective mechanisms are certainly included [247], The antiozonant activity accounts for a combination of a direct scavenging of ozone by the chemical AOZ and formation of... 

Chapter 6 deals with hydrogenation processes, usually based on the use of bifunctional catalysts. Plastic and rubber degradation in a hydrogen atmosphere is an effective treatment yielding highly saturated oils. Coliquefaction of plastics or rubber with coal is also considered. 

Polydiene rubbers were used for many years in low voltage electrical insulation because of their low electrical conductivity and flexibility. However, the traditional rubbers degrade by peroxidation relatively rapidly even when stabilised with antioxidants. This frequently leads to fires due to electrical shortage and, in recent decades, they have been largely replaced with saturated elastomeric materials e.g. EP rubbers... 

Unlike rubber-degrading actinomycete colonies, fungal colonies on latex-agar plates are not surro mded by transparent zones [5]. Superficial growth of fungi on NR films has been observed with a negligible consumption of the rubber [10]. Growth of the molds on rubber may have proceeded at the expense of the non-rubber constituents, like proteins in these cases. 

The rate of changes in modulus resulted from accelerated aging expressed by (Table 3.11). Those at 0.75 phr fullerene suggest that this filler substantially reduced the effects of rubber degradation. 

Since the near infrared Raman system used here is equipped with a microscope, the rubber degradation can be analysed with a spatial resolution of 1 pm. This section describes some of the areas related to the analysis of its blend and its IPN NR and its blend which have been investigated using this technique. 

Problems caused by rubber degradation occur when a seal is assembled into a component (such as a fuel pump or hydraulic system), especially, when that assembly goes into service. 

Undoubtedly, it is represented as a good potential for the conceptualization of CNTs-filled nitrile rubber for many reasons included, nitrile rubber degradation process occurred meanwhile the melt mixing procedure results in the formation of free-radicals on chains of polymer (Fang et al. 2011). This, in turn, increases the... 

Thermal degradation of rubber vulcanizates involves scission and cross-linking reactions. Tobolsky [9] did a kinetic study of rubber degradation and derived the following simple Maxwellian relation between the stress and the rate constant, k, based on the theory of rubber elasticity ... 

Mohler et al. [234] have reported TG-DSC-MS of the thermal decomposition of the vulcanisation accelerator tetramethylthiuramdisulfide (TMTD) in rubber degradation of TMTD starts at about 155°C, as evidenced by m/z 76 (CS2) and 44 (radical of the secondary dimethylamine). 

An examination is made of the mechanisms of rubber degradation, types of antiozonants and antioxidants used in rubbers, and the mechanisms by which they prevent polymer degradation. 10 refs. 

Butyl rubber is very resistant to water as well as to aqueous solutions of inorganic salts, acids, and alkalis, even at elevated temperature [32]. Strong acids and bases as well as strongly oxidizing solutions do not attack butyl rubber. Degradation occurs in strongly oxidizing acids, but not in their dilute solutions [697]. 

---