Claims:We Claim:
1. A process for preparing epoxidized rubber comprising reacting rubber with an oxidizing agent in presence of an acid catalyst,
wherein the process is carried out by sonication,
wherein the rubber is polybutadiene rubber (PBR), styrene-butadiene rubber (SBR) or butyl rubber (BR),
and wherein the epoxidized rubber is epoxidized polybutadiene rubber, epoxidized styrene-butadiene rubber or epoxidized butyl rubber.

2. The process as claimed in claim 1, wherein the process comprises reacting polybutadiene rubber (PBR) with an oxidizing agent in presence of an acid catalyst to obtain epoxidized polybutadiene rubber, wherein the process is carried out by sonication.

3. The process as claimed in claim 1, wherein the process comprises reacting styrene-butadiene rubber (SBR) with an oxidizing agent in presence of an acid catalyst to obtain epoxidized styrene-butadiene rubber, wherein the process is carried out by sonication.

4. The process as claimed in claim 1, wherein the process comprises reacting butyl rubber (BR) with an oxidizing agent in presence of an acid catalyst to obtain epoxidized butyl rubber, wherein the process is carried out by sonication.

5. The process as claimed in claim 1, wherein the sonication is ultrasonication; and wherein the ultrasonication employs a frequency ranging from about 10 kHz to 50 kHz.

6. The process as claimed in any of the preceding claims, wherein said process is carried out at room temperature.

7. The process as claimed in any of the preceding claims, wherein said process is carried out at a temperature ranging from about 15 ? to 30 ?, preferably about 25 ?.

8. The process as claimed in any of the preceding claims, wherein said process is carried out for a time period ranging from about 10 minutes to 60 minutes, preferably about 15 minutes to about 60 minutes.

9. The process as claimed in any of the preceding claims, wherein the oxidizing agent is a peroxide selected from a group consisting of hydrogen peroxide, peracetic acid, oxone, peracids and combinations thereof.

10. The process as claimed in any of the preceding claims, wherein the acid catalyst is selected from a group consisting of formic acid, acetic acid, aliphatic acids, aromatic acids and combinations thereof.

11. The process as claimed in any of the preceding claims, wherein the process comprises employing a solvent selected from a group consisting of benzene, toluene, cyclohexane, chloroform, tetrahydrofuran, aromatic hydrocarbon, aliphatic cyclic hydrocarbon and combinations thereof.

12. The process as claimed in any of the preceding claims, wherein the rubber is dissolved in a solvent selected from a group consisting of toluene, cyclohexane, chloroform, tetrahydrofuran and combinations thereof, to obtain a reactant rubber solution.

13. The process as claimed in any of the preceding claims, wherein the epoxidized rubber is isolated and optionally purified; and wherein said isolation and purification is carried out by acts selected from a group consisting of solvent extraction or precipitation of the product, filtration, washing, drying and combinations thereof, preferably a combination of precipitation using alcohol, filtration, washing and drying.

14. The process as claimed in any of the preceding claims, wherein the process comprises reacting rubber, hydrogen peroxide and formic acid, and subjecting the reaction to sonication to obtain epoxidized rubber; and wherein the process is carried out at room temperature for a time-period ranging from about 10 minutes to 60 minutes.

15. The process as claimed in any of the preceding claims, wherein the process comprises:
a) adding a mixture of formic acid and hydrogen peroxide to a solution of rubber, wherein the rubber is polybutadiene rubber (PBR), styrene-butadiene rubber (SBR) or butyl rubber (BR); and
b) subjecting the reaction mixture to ultrasonication to obtain the epoxidized rubber,
wherein the process is carried out at room temperature for a time-period ranging from about 10 minutes to 60 minutes.

16. The process as claimed in any of the preceding claims, wherein the process achieves epoxidation of rubber from about 1% to 50 %, and yield of the epoxidized rubber product ranges from about 50% to 95%.
, Description:TECHNICAL FIELD
[001]. The instant disclosure is in the field of chemical sciences, more particularly to synthetic chemistry and polymer science. The present disclosure relates to a process of epoxidation of rubbers. In an exemplary embodiment, the disclosure relates to a method of synthesizing epoxidized rubbers via. sonication.

BACKGROUND OF THE DISCLOSURE
[002]. Polybutadiene rubber (PBR) is a synthetic rubber/polymer formed from the polymerization of the monomer 1,3-butadiene. PBR is one of the most produced synthetic rubber after styrene-butadiene rubber (SBR), and is largely employed in applications related to automobile tires and plastics, amongst others.

[003]. Among various functionalizations of elastomers, epoxidation is a wonderful synthetic tool for introduction of versatile functionality to the rubber chain. Epoxidation is usually carried out to serve dual purpose, to improve the functionality, and also to enhance the polar character of the non-polar rubber and polymer chains. However, the known processes of functionalization/epoxidation of elastomers, especially PBR, SBR and butyl rubber (BR) adopt conventional refluxing and batch process which makes the synthesis complex as well as time consuming.

[004]. Therefore, there is a need to develop a simple, cost-effective and more efficient process for functionalization of rubbers, more particularly epoxidation of PBR, SBR and BR. The present disclosure tries to address said need.

SUMMARY OF THE DISCLOSURE
[005]. The present disclosure relates to a process for preparing epoxidized rubbers including epoxidized polybutadiene rubber, epoxidized styrene-butadiene rubber and epoxidized butyl rubber.

[006]. In an embodiment, the disclosure relates to a process for preparation of epoxidized rubbers by sonication.

[007]. In another embodiment, the present process for preparation of epoxidized rubber comprises reacting the rubber including polybutadiene rubber (PBR), styrene-butadiene rubber (SBR) or butyl rubber (BR) with an oxidizing agent in presence of an acid catalyst, wherein the process/reaction is carried out by sonication.

[008]. In yet another embodiment, the present process for preparation of epoxidized rubber is carried out at room temperature.

[009]. In still another embodiment, the present process for preparation of epoxidized rubber is carried out for a time period ranging from about 10 minutes to 60 minutes.

BRIEF DESCRIPTION OF THE ACCOMPANYING FIGURES
[0010]. In order that the disclosure may be readily understood and put into practical effect, reference will now be made to exemplary embodiments as illustrated with reference to the accompanying figures. The figures together with detailed description below, are incorporated in and form part of the specification, and serve to further illustrate the embodiments and explain various principles and advantages, where:

[0011]. Figure 1 depicts pictorial representation of the present process/set-up for preparing epoxidized polybutadiene rubber.

[0012]. Figure 2 depicts the NMR spectra of polybutadiene rubber (PBR).

[0013]. Figure 3 depicts the NMR spectra of epoxidized polybutadiene rubber at 60th minute [Figure 3(a)], 50th minute [Figure 3(b)], 45th minute [Figure 3(c)], and 40th minute [Figure 3(d)], respectively.

[0014]. Figure 4 depicts the NMR spectra of styrene-butadiene rubber (SBR).

[0015]. Figure 5 depicts the NMR spectra of epoxidized styrene-butadiene rubber at 60th minute.

[0016]. Figure 6 depicts the NMR spectra of epoxidized styrene-butadiene rubber at 30th minute.

[0017]. Figure 7 depicts the NMR spectra of butyl rubber (BR).

[0018]. Figure 8 depicts the NMR spectra of epoxidized butyl rubber at 60th minute.

[0019]. Figure 9 depicts the NMR spectra of epoxidized butyl rubber at 30th minute.

STATMENT OF THE DISCLOSURE
[0020]. The present disclosure relates to a process for preparing epoxidized rubber comprising reacting rubber with an oxidizing agent in presence of an acid catalyst; wherein the process is carried out by sonication; wherein the rubber is polybutadiene rubber (PBR), styrene-butadiene rubber (SBR) or butyl rubber (BR); and wherein the epoxidized rubber is epoxidized polybutadiene rubber, epoxidized styrene-butadiene rubber or epoxidized butyl rubber.

DESCRIPTION OF THE DISCLOSURE
[0021]. As used herein, the terms/phrases ‘polybutadiene’, ‘polybutadiene rubber’ and ‘PBR’ are employed interchangeably in the present disclosure.

[0022]. As used herein, the terms/phrases ‘styrene-butadiene’, ‘styrene-butadiene rubber’ and ‘SBR’ are employed interchangeably in the present disclosure.

[0023]. As used herein, the terms/phrases ‘butyl rubber’ and ‘BR’ are employed interchangeably in the present disclosure.

[0024]. In the present disclosure, a method is provided to functionalize elastomers at olefinic moiety. In particular, in order to address the limitations as stated in the background, the present disclosure provides a simple and efficient process for epoxidation of rubbers including polybutadiene rubber (PBR), styrene-butadiene rubber (SBR) and butyl rubber (BR).

[0025]. The present disclosure provides a process of epoxidation of rubbers wherein said process is performed via. sonication. In other words, sonication method is employed in the present process to catalyze the epoxidation of rubbers including PBR, SBR and BR. The employment of sonication, more particularly ultrasonication in chemical reactions give rise to a physical phenomenon between molecules known as acoustic cavitation. When ultrasound is applied in a solvent, there exists equilibrium of compression and expansion of liquid in which sudden drop in pressure generates small and oscillating bubbles of gaseous substances. These bubbles continuously expand with each cycle of sonication until they reach unstable size, and at this point they tend to collide or violently collapse. Such collapses explicitly bring reagent molecules for effective collision with efficiency superior than collision that occurs in conventional processes. Furthermore, sonication was found to be very effective in the present epoxidation reactions which employ both organic and aqueous phases and do not require any phase transfer catalysts.

[0026]. In an exemplary embodiment, the present disclosure provides a process for preparing epoxidized polybutadiene rubber comprising reacting polybutadiene rubber (PBR) with an oxidizing agent in presence of an acid catalyst, wherein the process is carried out by sonication.

[0027]. In an embodiment of the present disclosure, any known polybutadiene rubber (PBR) can be employed in the present process of epoxidized PBR synthesis. Typically, polybutadiene rubber having average molecular weight ranging from 2 × 105 to 5 × 105 g/mol can be employed in the present process.

[0028]. In another exemplary embodiment, the present disclosure provides a process for preparing epoxidized styrene-butadiene rubber comprising reacting styrene-butadiene rubber (SBR) with an oxidizing agent in presence of an acid catalyst, wherein the process is carried out by sonication.

[0029]. In an embodiment of the present disclosure, any known styrene-butadiene rubber (SBR) can be employed in the present process of epoxidized styrene-butadiene rubber synthesis. Typically, styrene-butadiene rubber having average molecular weight ranging from 4 × 105 to 7 × 105 g/mol can be employed in the present process.

[0030]. In another exemplary embodiment, the present disclosure provides a process for preparing epoxidized butyl rubber comprising reacting butyl rubber (BR) with an oxidizing agent in presence of an acid catalyst, wherein the process is carried out by sonication.

[0031]. In an embodiment of the present disclosure, any known butyl rubber (BR) can be employed in the present process of epoxidized butyl rubber synthesis. Typically, butyl rubber having average molecular weight ranging from 2 × 105 to 6 × 105 g/mol can be employed in the present process.

[0032]. In another embodiment of the present disclosure, the sonication employed in the process of epoxidized rubber synthesis including epoxidized PBR, epoxidized SBR or epoxidized BR, is ultrasonication.

[0033]. In yet another embodiment of the present disclosure, the ultrasonication is employed at a frequency ranging from about 10 kHz to 50 kHz.

[0034]. In a preferred embodiment of the present disclosure, the process of epoxidized rubber synthesis including epoxidized PBR, epoxidized SBR or epoxidized BR, is carried out at room temperature.

[0035]. In another embodiment of the present disclosure, the process of epoxidized rubber synthesis including epoxidized PBR, epoxidized SBR or epoxidized BR, is carried out at a temperature ranging from about 15 ? to 30 ?, preferably 25 ? to 30 ?.

[0036]. In an exemplary embodiment of the present disclosure, the process of epoxidized rubber synthesis including epoxidized PBR, epoxidized SBR or epoxidized BR, is carried out at about 25 ?.

[0037]. In a preferred embodiment of the present disclosure, the process of epoxidized rubber synthesis including epoxidized PBR, epoxidized SBR or epoxidized BR, is completed in a time period ranging from about 10 minutes to 60 minutes, preferably 15 minutes to 60 minutes.

[0038]. In an exemplary embodiment of the present disclosure, the process of epoxidized rubber synthesis including epoxidized PBR, epoxidized SBR or epoxidized BR, is carried out for about 30 minutes.

[0039]. In an exemplary embodiment of the present disclosure, the process of epoxidized rubber synthesis including epoxidized PBR, epoxidized SBR or epoxidized BR, is carried out for about 45 minutes.

[0040]. In another exemplary embodiment of the present disclosure, the process of epoxidized synthesis including epoxidized PBR, epoxidized SBR or epoxidized BR, is carried out for about 60 minutes.

[0041]. In another exemplary embodiment of the present disclosure, the process of epoxidized rubber synthesis including epoxidized PBR, epoxidized SBR or epoxidized BR, is completed in about 40 minutes to 60 minutes.

[0042]. In an embodiment of the present disclosure, the oxidizing agent employed in the process is a peroxide selected from a group consisting of hydrogen peroxide, peracetic acid, oxone, peracids and combinations thereof.

[0043]. In another embodiment of the present disclosure, the acid catalyst employed in the process is selected from a group consisting of formic acid, acetic acid, aliphatic acids and combinations thereof.

[0044]. In yet another embodiment of the present disclosure, the process of epoxidized rubber synthesis including epoxidized PBR, epoxidized SBR or epoxidized BR, employs a solvent selected from a group consisting of benzene, toluene, cyclohexane, chloroform, tetrahydrofuran, aromatic hydrocarbon, aliphatic cyclic hydrocarbon and combinations thereof.

[0045]. In an exemplary embodiment of the present disclosure, the process of synthesizing epoxidized rubber including epoxidized PBR, epoxidized SBR or epoxidized BR further comprises dissolving the rubber in a solvent selected from a group consisting of toluene, cyclohexane, chloroform, tetrahydrofuran and combinations thereof, to obtain a rubber solution, wherein said solution is employed along with oxidizing agent and acid catalyst for epoxidized rubber synthesis.

[0046]. In another embodiment of the present disclosure, the synthesized epoxidized rubber including epoxidized PBR, epoxidized SBR or epoxidized BR is isolated and optionally purified.

[0047]. In yet another embodiment of the present disclosure, the isolation and purification of the synthesized epoxidized rubber is carried out by acts selected from a group consisting of solvent extraction or precipitation of the product, filtration, washing, drying and combinations thereof.

[0048]. In an exemplary embodiment of the present disclosure, the synthesized epoxidized rubber is precipitated using alcohol, filtered, washed and dried.

[0049]. In an embodiment, the present process/set-up for preparing epoxidized rubber is pictorially represented in Figure 1.

[0050]. In an exemplary embodiment of the present disclosure, reaction scheme depicting the present process of preparation of epoxidized rubber including epoxidized PBR, epoxidized SBR or epoxidized BR via. sonication technique is provided below under Scheme 1.

Scheme 1: Reaction scheme depicting the process of present invention

[0051]. In the general process of the present disclosure, rubber (PBR, SBR or BR) is dissolved in a solvent to obtain a rubber solution. To this solution, mixture of oxidizing agent and acid catalyst is added drop wise. Solution is subjected to sonication for about 10 minutes to 60 minutes at room temperature from the time of addition completion. The reaction suspension is then added to methanol to precipitate out the epoxide product, followed by filtration and drying the product.

[0052]. In an embodiment of the present process, the rubber solution of PBR, SBR or BR is prepared by dissolving/solubilizing the rubber in presence of a solvent, preferably toluene.

[0053]. In an exemplary embodiment of the present process, the epoxidation of rubber including PBR, SBR or BR, is performed at room temperature or at a temperature between 15 oC to 30 oC by employing hydrogen peroxide as the oxidizing agent and formic acid as the acid catalyst and using an ultrasonication equipment.

[0054]. In another exemplary embodiment of the present process, the epoxidation of rubber including PBR, SBR or BR, is performed at room temperature or at a temperature between 15 oC to 30 oC for a time-period of about 10 minutes to 60 minutes, by employing hydrogen peroxide as the oxidizing agent and formic acid as the acid catalyst and using an ultrasonication equipment.

[0055]. In a preferred embodiment of the present disclosure, the process of preparing epoxidized rubber including epoxidized PBR, epoxidized SBR or epoxidized BR, via. ultrasonication comprises reacting the rubber (PBR, SBR or BR), hydrogen peroxide and formic acid wherein the reaction is catalyzed by ultrasonication, to obtain the epoxidized rubber, and wherein said process is carried out at room temperature for a time-period of about 10 minutes to 60 minutes.

[0056]. Additional embodiments and features of the present disclosure will be apparent to one of ordinary skill in art based upon description provided herein. The embodiments herein provide various features and advantageous details thereof in the description. Descriptions of well-known/conventional methods/steps and techniques are omitted so as to not unnecessarily obscure the embodiments herein. Further, the disclosure herein provides for examples illustrating the above described embodiments, and in order to illustrate the embodiments of the present disclosure certain aspects have been employed. The examples used herein for such illustration are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the following examples should not be construed as limiting the scope of the embodiments herein.

EXAMPLES
[0057]. Exemplary experiments were performed with hydrogen peroxide as the oxidizing agent, formic acid as the catalyst and toluene as the solvent. The reagents and the concentrations employed are - hydrogen peroxide: 50 %, PBR, SBR, BR solution: 5 %, formic acid: 98 %, and methanol & toluene as coagulating agent and solvent respectively are AR grade.

EXAMPLE 1:
Synthesis of epoxidized polybutadiene rubber by heating
[0058]. Polybutadiene rubber (5 g) was dissolved in 100 mL of toluene. This solution was taken in a 500 mL conical flask and to this suspension a mixture formic acid (HCOOH, about 2.8 mL; 0.74 mol) and hydrogen peroxide (H2O2) in water of 50 % (about 1.8 mL; 0.074 mol) was added via. additional funnel drop wise. Reaction mixture was heated at about 80 oC for about 7 hours, cooled and coagulated by adding methanol. The product was washed three times with water and dried in vacuum oven.

[0059]. EXAMPLE 2:
Synthesis of epoxidized polybutadiene rubber by sonication
[0060]. In all the experiments, polybutadiene rubber (PBR) was dissolved in 100 mL of toluene. This solution was taken in a 500 mL conical flask and to this suspension a mixture formic acid (HCOOH, about 2.8 mL; 0.74 mol, or 11.2 mL) and hydrogen peroxide (H2O2) in water of 50 % (about 1.8 mL; 0.074 mol, or 6.8 mL) was added via. additional funnel drop wise and sonicated. Ultrasonication was performed at room temperature (15? to 30?) for a time period of about 10 minutes to 60 minutes. The obtained reaction suspension was then added to methanol to precipitate out the epoxide product. The epoxide product was washed with water three times, filtered and dried to get polymer yield between 50% to 95% with epoxidation content between 1% to 22%. The experiments indicating the process conditions and the quantities of PBR, H2O2 and HCOOH, and the corresponding results are provided in Table 1 below.

Table 1: Synthesis of epoxidized polybutadiene rubber by sonication

Experiment
No. PBR
(g) H2O2
(mL) HCOOH
(mL) Solvent Reaction
method Reaction
time Remarks Yield
(%) Epoxidation
(%)
1 5 1.8 2.8 Toluene Heating 7 hours Epoxidation 86 16
2 5 1.8 2.8 Toluene Sonication 40 minutes Epoxidation 82 7
3 5 1.8 2.8 Toluene Sonication 45 minutes Epoxidation 89 9
4 5 1.8 2.8 Toluene Sonication 50 minutes Epoxidation 85 14
5 5 1.8 2.8 Toluene Sonication 60 minutes Epoxidation 81 22
6 20 6.8 11.2 Toluene Sonication 60 minutes Epoxidation 90 18

[0061]. As observed from the above experimental results, the present epoxidation process employing sonication method successfully yielded epoxidized product when the present process/reaction was carried out at room temperature for a shorter time-period such as between 10 minutes to 60 minutes. The obtained epoxidized product was further characterized by IR Spectroscopy and NMR Spectroscopy to confirm the formation of epoxidized polybutadiene rubber. The spectral diagrams showcasing polybutadiene rubber and the formation of epoxidized polybutadiene rubber at various time-periods (eg. 40th minute, 45th minute, 50th minute, and 60th minute) are provided under Figures 2 and 3, respectively. On the other hand, the conventional process (heating method) required higher temperature and a longer time duration to obtain the epoxidized product.

[0062]. EXAMPLE 3:
Synthesis of epoxidized styrene-butadiene rubber by sonication
[0063]. Styrene butadiene (SBR) (5 g) was dissolved in 100 mL of toluene in a 500 mL conical flask, and to this suspension a mixture of formic acid (HCOOH, 1.4 mL; 0.02 mol) and hydrogen peroxide (H2O2) in water of 50 % (1.16 mL; 0.02 mol) was added via. additional funnel drop wise and sonicated. Ultrasonication was performed at room temperature (15? to 30?) for a time period of about 30 minutes to 60 minutes. The obtained reaction suspension was then added to methanol to precipitate out the epoxide product. The epoxide product was washed with water three times, filtered and dried to get polymer yield of 89 % with epoxidation content of 17 %. The obtained epoxidized product was further characterized by NMR Spectroscopy to confirm the formation of epoxidized styrene butadiene rubber. The spectral diagrams are provided under Figures 4-6.

[0064]. EXAMPLE 4:
Synthesis of epoxidized butyl rubber by sonication
[0065]. Butyl rubber (BR) (5 g) dissolved in 100 mL of toluene in a 500 mL conical flask and to this suspension a mixture of formic acid (HCOOH, 1.36 mL; 0.03 mol) and hydrogen peroxide (H2O2) in water of 50 % (1.67 mL; 0.03 mol,) was added via. additional funnel drop wise and sonicated. Ultrasonication was performed at room temperature (15? to 30?) for a time period of about 30 minutes to 60 minutes. The obtained reaction suspension was then added to methanol to precipitate out the epoxide product. The epoxide product was washed with water three times, filtered and dried to get polymer yield of 86 % with epoxidation content of 0.56 %. It has to be noted here that 0.56 % epoxidation content is because butyl rubber has maximum double bonds of about only 2 % since butyl rubber is a copolymer of 98 % isobutylene and 2 % of isoprene. The obtained epoxidized product was further characterized by NMR Spectroscopy to confirm the formation of epoxidized butyl rubber. The spectral diagrams are provided under Figures 7-9.

ADVANTAGES
[0066]. The present disclosure provides advantages including but not limiting to the following:
(a) the present process utilizing ultrasonication technique is a simple and alternate method when compared to the complex and conventional batch process for functionalization/epoxidation of rubbers including PBR, SBR and BR.
(b) the present process requires low temperature, particularly room temperature or a temperature ranging from about 15 ? to 30? to complete the epoxidation process in contrast to a temperature requirement of about 70? or more in conventional methods (eg. heating method).
(c) since a powerful oxidizing agent such as peroxide is employed in the reaction mixture, performing the epoxidation reaction at lower temperature is highly beneficial.
(d) time consumption for the present process is minimal, wherein the process is completed in about 10 minutes to 1 hour compared to batch process which takes much longer time for completion.
(e) the present process occurs under mild conditions (eg. under room temperature) which avoids degradation of material(s) during the course of reaction.
(f) the requirement of phase transfer catalyst(s) is avoided in the present process as sonication is very effective for two phase reactions.
(g) the present process is cleaner and green process as is operates at lower temperature and at reduced time.
(h) The present process is cost effective/economical due to the above-mentioned features.

[0067]. Additional embodiments and features of the present disclosure will be apparent to one of ordinary skill in art based on the description provided herein. The embodiments herein provide various features and advantageous details thereof in the description. Descriptions of well-known/conventional methods and techniques are omitted so as to not unnecessarily obscure the embodiments herein.

[0068]. The foregoing description of the specific embodiments fully reveals the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments in this disclosure have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

[0069]. Throughout this specification, the word “comprise”, or variations such as “comprises” or “comprising” wherever used, will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

[0070]. With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

[0071]. Any discussion of documents, acts, materials, devices, articles and the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.

[0072]. While considerable emphasis has been placed herein on the particular features of this disclosure, it will be appreciated that various modifications can be made, and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other modifications in the nature of the disclosure or the preferred embodiments will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.