Description:TECHNICAL FIELD
The present disclosure relates to polymer chemistry. The disclosure particularly relates to method of detecting popcorn polymer or peroxide radical in a sample. The disclosure also relates to method of separating popcorn polymer from respective parent polymer in a sample. The methods of detecting popcorn polymer or peroxide radical and separating popcorn polymer is simple, economical and effective.

BACKGROUND OF THE DISCLOSURE
1, 3-butadiene (BD) is one of the widely used monomers in elastomer industries. It is an important component in various elastomeric polymers such as polybutadiene, styrene-butadiene rubber or nitrile butadiene rubber. The presence of conjugated double bonds in butadiene makes it extremely reactive towards molecular oxygen (available in air) to form polyperoxides with -O-O- linkages. Such oxidation reactions are tremendously dangerous and exothermic in nature. Therefore, fire and explosions are very common to all butadiene related plants, caused by the BD-polyperoxides. Hence, proper investigation of BD oxidation for peroxide formulation and identification of popcorn polymer are among the major concerns in the elastomer industries to avoid hazardous accidents.

The available method for identification of popcorn polymer is based on the kinetics of styrene polymerization which takes hours (longer duration) for detection of popcorn seeds and it is not feasible for on field detection of the popcorn seeds.

Thus, there is a need for simple and efficient method for detection of popcorn polymer in sample, in significantly reduced time so that such method can be employed for on field detection of popcorn polymer.

STATEMENT OF THE DISCLOSURE
Accordingly, the present disclosure describes a simple, economical and efficient method for detection of popcorn polymer or peroxide radical in a sample, wherein the method does not require any sophisticated instrument and is capable of detecting popcorn polymer or peroxide radical in about 5 minutes.

The method for detecting popcorn polymer or peroxide in a sample, comprises- exposing the sample to combination of light and photochromic compound to detect the popcorn polymer or peroxide radical in the sample.
The present disclosure further describes a method of separating popcorn polymer from respective parent polymer in a sample suspected of having the popcorn polymer, comprises- exposing the sample to combination of light and photochromic compound, followed by separating the popcorn polymer from the respective parent polymer.

BRIEF DESCRIPTION OF THE ACCOMPANYING FIGURES
In order that the present 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 figure. The figure 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:

FIGURE 1 provides a pictograph of (a) butadiene popcorn in water and (b) air dried butadiene popcorn.

FIGURE 2 provides a pictograph of photochromic dye upon irradiation with UV-light having wavelength of about 365 nm for about 1 minute.

FIGURE 3 illustrates change in optical appearances of popcorn polymer (butadiene) and polybutadiene rubber (parent polymer), following combinatorial exposure to photochromic compound and light having wavelength of about 365 nm (UV light).

FIGURE 4 illustrates change in optical appearances of popcorn polymer (butadiene) and polybutadiene rubber (parent polymer), following combinatorial exposure to photochromic compound and light having wavelength of about 365 nm (UV light).

FIGURE 5 illustrates change in optical appearances of popcorn polymer (butadiene) and polybutadiene rubber (parent polymer), following combinatorial exposure to photochromic compound and light having wavelength ranging from about 395 nm to 400 nm (UV light).

FIGURE 6 illustrates change in optical appearances of popcorn polymer (butadiene) and polybutadiene rubber (parent polymer), following combinatorial exposure to photochromic compound, such as spiropyran and full spectrum of sunlight.

FIGURE 7 illustrates change in optical appearances of popcorn polymer (butadiene) and polybutadiene rubber (parent polymer), following combinatorial exposure to photochromic compound, such as spirooxazine and full spectrum of sunlight.

FIGURE 8 illustrates change in optical appearance of peroxide radical, such as benzoyl peroxide (BPO) and photochromic compound alone, following combinatorial exposure to photochromic compound and light having wavelength of about 365 nm (UV light).

FIGURE 9 provides schematic representation of the method for detecting popcorn polymer from the sample by change in the optical appearance.

FIGURE 10 illustrates change in optical appearances of popcorn polymer (styrene butadiene popcorn polymer) and SBR rubber (parent polymer), following combinatorial exposure to photochromic compound, and light.

FIGURE 11 illustrates separation of styrene butadiene rubber part (SBR part) (blue) and SBR popcorn polymer (pink).

DETAILED DESCRIPTION OF THE DISCLOSURE
Unless otherwise defined, all terms used in the disclosure, including technical and scientific terms, have meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. By means of further guidance, term definitions are included for better understanding of the present disclosure.

As used herein, the singular forms ‘a’, ‘an’ and ‘the’ include both singular and plural referents unless the context clearly dictates otherwise.

The term ‘comprising’, ‘comprises’ or ‘comprised of’ as used herein are synonymous with ‘including’, ‘includes’, ‘containing’ or ‘contains’ and are inclusive or open-ended and do not exclude additional, non-recited members, elements or method steps.

The recitation of numerical ranges by endpoints includes all numbers and fractions subsumed within the respective ranges, as well as the recited endpoints.

The term ‘about’ as used herein when referring to a measurable value such as a parameter, an amount, a temporal duration, and the like, is meant to encompass variations of ±10% or less, preferably ±5% or less, more preferably ±1% or less and still more preferably ±0.1% or less of and from the specified value, insofar such variations are appropriate to perform the present disclosure. It is to be understood that the value to which the modifier ‘about’ refers is itself also specifically, and preferably disclosed.

Reference throughout this specification to ‘some embodiments’, ‘one embodiment’ or ‘an embodiment’ means that a particular feature, structure or characteristic described in connection with the embodiment may be included in at least one embodiment of the present disclosure. thus, the appearances of the phrases ‘in some embodiments’, ‘in one embodiment’ or ‘in an embodiment’ in various places throughout this specification may not necessarily all refer to the same embodiment. It is appreciated that certain features of the disclosure, which are for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the disclosure, which are, for brevity described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.

As used herein ‘popcorn polymer’ refers to polymeric resinous material which resembles popcorn in appearance. It is a porous material, like a macroporous copolymer with a small specific inner surface. Popcorn polymers are known to have formed due to free radical mechanism. In the present disclosure, the popcorn polymer refers to those derived during polymerization of monomers including but it is not limited to Styrene, divinylbenzene, methyl acrylate, butadiene, isoprene and N- vinyl-2-pyrrolidone.

As used herein ‘change in optimal appearance’ refers to change in the colour of the popcorn polymer upon exposure to photochromic compound when compared to parent polymer. For instance, distinct colour noted in the popcorn polymer includes but it is not limited to pink, Violet, Indigo, Blue, green, yellow, orange, red and any combination of these colours when compared to parent polymer.

The present disclosure relates to simple, economical and environmentally friendly process for detecting popcorn polymer or peroxide radical in a sample suspected of having popcorn polymer or peroxide radical.
In some embodiments of the present disclosure, the method of detecting the popcorn polymer in a sample suspected of having popcorn polymer, comprises- exposing the sample to combination of light and photochromic compound to detect the popcorn polymer in the sample

In some embodiment of the present disclosure, the photochromic compound is selected from a group comprising Spiropyran, Spirooxazine, Dithienylethene, dihydroazulene, indoline,naphthopyran, dihydropyrene, phenoxynaphthacenequinone, azobenzene, fulgimide, semicarbazones, bianthrone, phenylhydrazine, phenylosazone, naphthalenone, 2,3,4,4-tetrachloronaphthalen-1-(4H)-one, azines, thioindigoides, dinitrobenzylpyridine, Fulgides, derivatives thereof and any combination thereof.

In some embodiments of the present disclosure, the photochromic compound is in an amount ranging from about 0.001 wt% to 10 wt%, including all the values in the range, for instance, 0.002 wt%, 0.003 wt%, 0.004 wt%, 0.005 wt% and so on and so forth.

In some embodiments of the present disclosure, the light is selected from a group comprising UV light, visible light and light emitted from electronic devices. In some embodiments, the visible light is full spectrum sunlight.

In some embodiment of the present disclosure, the light is UV light having wavelength ranging from about 250 nm to 400 nm, including all the values in the range, for instance, 251 nm, 252 nm, 253 nm, 254 nm and so on and so forth.

In some embodiments of the present disclosure, the light is visible light having wavelength ranging from about 400 nm to 750 nm, including all the values in the range, for instance, 401 nm, 402 nm, 403 nm, 404 nm and so on and so forth.

In some embodiments of the present disclosure, the light is from any source or combination of sources having frequency range of about 1 Hz to 1000 Hz and radiation intensity range of about 1 watt to 1000 watt.

In some embodiments of the present disclosure, the exposing described in the method comprises-
a) contacting the sample with the photochromic compound; and
b) irradiating the sample with light.

In some embodiments of the present disclosure, the contacting comprises- mixing the sample with about 0.001 wt% to 10 wt% of the photochromic compound. In an embodiment, the photochromic compound is present in any value within the range of about 0.001 wt% to 10 wt%, for instance, 0.001 wt%, 0.002 wt%, 0.003 wt%, 0.004 wt% and so on and so forth.

In an exemplary embodiment, the photochromic compound is dissolved in solvent prior to mixing with the sample to obtain solution of photochromic compound. In an embodiment, the solvent is selected from a group comprising, toluene, cyclohexane, tetrahydrofuran, chloroform, dichloromethane, hexane, benzene, chlorobenzene, dichlorobenzene, diethyl ether, ethyl acetate, acetone and any combination thereof. In an embodiment, the photochromic compound in the solution is in an amount ranging from about 0.001 wt% to 10 wt%, including all the values in the range, for instance, 0.001 wt%, 0.002 wt%, 0.003 wt%, 0.004 wt% and so on and so forth.

In some embodiments of the present disclosure, irradiating the sample with the light is carried out for a duration ranging from about 1 second to 60 minutes, including all the values in the range, for instance, 2 second, 3 second, 4 second, 5 second and so on and so forth. In an embodiment, the light is UV light having wavelength ranging from about 250 nm to 400 nm, including all the values in the range for instance, 251 nm, 252 nm, 253 nm, 254 nm and so on and so forth. In an alternate embodiment, the light is visible light having wavelength ranging from about 400 nm to 750 nm, including all the values in the range, for instance, 401 nm, 402 nm, 403 nm, 404 nm and so on and so forth. Inventors have identified that duration of irradiation is dependent on size of the sample and nature of the sample employed, and intensity of the light employed. However, about 5 minutes of irradiation is preferred for detection of popcorn polymer or peroxide radical from any time of sample by employing UV light having wavelength ranging from about 250 nm to 400 nm or visible light having wavelength ranging from about 400 nm to 750 nm.

In some embodiments of the present disclosure, the exposing comprises:
a) irradiating the sample with light;
b) contacting the sample with the photochromic compound; and
c) irradiating the sample with light again.
In some embodiments of the present disclosure, the irradiating in the step a) is carried out for a duration ranging from about 1 second to 60 minutes. In an embodiment, irradiation is by UV light having wavelength ranging from about 250 nm to 400 nm, including all the values in the range for instance, 251 nm, 252 nm, 253 nm, 254 nm and so on and so forth. In an alternate embodiment, the irradiation is by visible light having wavelength ranging from about 400 nm to 750 nm, including all the values in the range, for instance, 401 nm, 402 nm, 403 nm, 404 nm and so on and so forth.

In some embodiments of the present disclosure, the contacting in the step b) comprises mixing the sample with about 0.001 wt% to 10 wt% of the photochromic compound. In an embodiment, the photochromic compound is present in any value within the range of about 0.001 wt% to 10 wt%, for instance, 0.001 wt%, 0.002 wt%, 0.003 wt%, 0.004 wt% and so on and so forth.

In an exemplary embodiment, the photochromic compound is dissolved in solvent prior to mixing with the sample to obtain solution of photochromic compound. In an embodiment, the solvent is selected from a group comprising, toluene, cyclohexane, tetrahydrofuran, chloroform, dichloromethane, hexane, benzene, chlorobenzene, dichlorobenzene, diethyl ether, ethyl acetate, acetone, and any combination thereof. In an embodiment, the photochromic compound in the solution in an amount ranging from about 0.001 wt% to 10 wt%, including all the values in the range, for instance, 0.001 wt%, 0.002 wt%, 0.003 wt%, 0.004 wt% and so on and so forth.

In some embodiments of the present disclosure, the irradiating in the step c) is carried out for a duration ranging from about 1 second to 60 minutes. In an embodiment, irradiation is by UV light having wavelength ranging from about 250 nm to 400 nm, including all the values in the range for instance, 251 nm, 252 nm, 253 nm, 254 nm and so on and so forth. In an alternate embodiment, the irradiation is by visible light having wavelength ranging from about 400 nm to 750 nm, including all the values in the range, for instance, 401 nm, 402 nm, 403 nm, 404 nm and so on and so forth.

In some embodiments of the present disclosure, the detecting popcorn polymer according to the above described method is carried out by colour appearance of the popcorn polymer, wherein the colour of the popcorn polymer is different from the colour of non-popcorn polymer or respective parent polymer in the sample. That is, there is change in optical appearances of popcorn polymer and respective parent polymer in the sample.

In an exemplary embodiment, the popcorn polymer appears pink in colour upon exposing the sample to combination of the light and the photochromic compound. In an exemplary embodiment, the parent polymer appears blue in colour upon exposing the sample to combination of the light and the photochromic compound. Thus, there is evident change in optical appearance of the popcorn polymer and the parent polymer, enabling efficient detection of the popcorn polymer in the sample according to the above described method.

In an embodiment, the popcorn polymer detected according to the method of the present disclosure includes but it is not limited to butadiene popcorn polymer, styrene butadiene popcorn polymer. Change in the optical appearance of the popcorn polymer from their respective parent polymer, such as polybutadiene and styrene butadiene rubber enable simple and efficient detection of the popcorn polymer.

The inventors have identified that the radicals on the popcorn polymer reacts effectively with the zwitter ionic isomers of photochromic compounds in presence of light, such as UV light and/or visible light (sun light, i.e., full spectrum of sunlight). Thus, there is change in the colour of the photochromic compound on the popcorn polymer. However, the parent polymer of the popcorn does not contain any radicals, as a result, the parent polymer takes up the colour of the photochromic compound in presence of light, such as UV light and/or visible light. Thus, there is change in the optical appearance of the popcorn polymer (e.g., pink in colour) and parent polymer (blue in colour, which is the colour of the photochromic compound). Further, the Inventors identified that when the sample is irradiated with full spectrum of sunlight, the -O-O bonds in the sample (popcorn polymer) absorb UV part of the full spectrum and form radicals that lead to change in optical appearance.

In an embodiment, the Figures 3 and 4 illustrate change in optical appearances of popcorn polymer and polybutadiene (parent polymer) upon following the steps described in the method described above. The difference in the optical appearance of the popcorn polymer (pink in colour) and polybutadiene enables efficient detection of the popcorn polymer from polybutadiene (blue in colour).

In an embodiment, the Figure 5 illustrates illustrate change in optical appearances of popcorn polymer and polybutadiene (parent polymer) upon following the steps described in the method described above. The difference in the optical appearance of the popcorn polymer (pink in colour) and polybutadiene enables efficient detection of the popcorn polymer from polybutadiene (blue in colour).

In an embodiment, the Figures 6 and 7 illustrates change in optical appearances of popcorn polymer (butadiene) and polybutadiene (parent polymer), following combinatorial exposure to spiropyran and spirooxazine, individually and light, respectively.

In an embodiment, the Figure 9 provides schematic representation of the method of detecting popcorn polymer from the sample according to the present disclosure. The Figure 9 illustrates that there is change in optical appearance of the popcorn polymer and the parent polymer in the sample.

In some embodiments, the present disclosure relates to method of detecting peroxide radical in a sample suspected of having peroxide radical, said method comprises- exposing the sample to combination of light and photochromic compound to detect the peroxide radical in the sample.

In some embodiments of the present disclosure, the peroxide radical includes but it is not limited to benzoyl peroxide (BPO), hydrogen peroxide, benzoyl peroxide, dicumyl peroxide, acetyl acetone peroxide, acetyl benzoyl peroxide, ascaridole, tert-Butyl hydroperoxide, di-(1-naphthoyl)peroxide, diacetyl peroxide, ethyl hydroperoxide, methyl ethyl ketone peroxide, and any combination thereof.

In some embodiments of the present disclosure, in the method of detecting the peroxide radical, the photochromic compound is selected from a group comprising Spiropyran, Spirooxazine, Dithienylethene, dihydroazulene, indoline,naphthopyran, dihydropyrene, and phenoxynaphthacenequinone, azobenzene, fulgimide, semicarbazones, bianthrone, phenylhydrazine, phenylosazone, and naphthalenone, 2,3,4,4-tetrachloronaphthalen-1-(4H)-one, azines and thioindigoides, dinitrobenzylpyridine, Fulgides, derivatives thereof or any combination thereof. In an embodiment, the photochromic compound is in an amount ranging from about 0.001 wt% to 10 wt%, including all the values in the range, for instance, 0.002 wt%, 0.003 wt%, 0.004 wt%, 0.005 wt% and so on and so forth.
In some embodiments of the present disclosure, in the method of detecting the peroxide radical, the light is UV light having wavelength ranging from about 250 nm to 400 nm, including all the values in the range, for instance, 251 nm, 252 nm, 253 nm, 254 nm and so on and so forth.

In some embodiments of the present disclosure, in the method of detecting the peroxide radical,
the light is visible light having wavelength ranging from about 400 nm to 750 nm, including all the values in the range, for instance, 401 nm, 402 nm, 403 nm, 404 nm and so on and so forth.

In some embodiments of the present disclosure, in the method of detecting the peroxide radical, the exposing comprises-
a) contacting the sample with the photochromic compound; and
b) irradiating the sample with light.

In some embodiments of the present disclosure, in the method of detecting the peroxide radical, the contacting comprises- mixing the sample with about 0.001 wt% to 10 wt% of the photochromic compound. In an embodiment, the photochromic compound is present in any value within the range of about 0.001 wt% to 10 wt%, for instance, 0.001 wt%, 0.002 wt%, 0.003 wt%, 0.004 wt% and so on and so forth. In an alternate embodiment, the contacting involves- spreading the photochromic compound in solution form or in solid form (solid powder).

In some embodiments of the present disclosure, in the method of detecting the peroxide radical, irradiating the sample with the light is carried out for a duration ranging from about 1 second to 60 minutes. In an embodiment, the light is UV light having wavelength ranging from about 250 nm to 40nm, including all the values in the range for instance, 251 nm, 252 nm, 253 nm, 254 nm and so on and so forth. In an alternate embodiment, the light is visible light having wavelength ranging from about 400 nm to 750 nm, including all the values in the range, for instance, 401 nm, 402 nm, 403 nm, 404 nm and so on and so forth.

In some embodiments of the present disclosure, in the method of detecting the peroxide radical, the exposing comprises-
a) irradiating the sample with light;
b) contacting the sample with the photochromic compound; and
c) irradiating the sample with light again.

In some embodiments of the present disclosure, in the method of detecting the peroxide radical, the irradiating in the step a) is carried out for a duration ranging from about 1 second to 60 minutes. In an embodiment, irradiation is by UV light having wavelength ranging from about 250 nm to 400 nm, including all the values in the range for instance, 251 nm, 252 nm, 253 nm, 254 nm and so on and so forth. In an alternate embodiment, the irradiation is by visible light having wavelength ranging from about 400 nm to 750 nm, including all the values in the range, for instance, 401 nm, 402 nm, 403 nm, 404 nm and so on and so forth.

In some embodiments of the present disclosure, in the method of detecting the peroxide radical, the contacting in the step b) comprises mixing the sample with about 0.001 wt% to 10 wt% of the photochromic compound. In an embodiment, the photochromic compound is any value within the range of about 0.001 wt% to 10 wt%, for instance, 0.001 wt%, 0.002 wt%, 0.003 wt%, 0.004 wt% and so on and so forth.

In some embodiments of the present disclosure, in the method of detecting the peroxide radical, the irradiating in the step c) is carried out for a duration ranging from about 1 second to 60 minutes. In an embodiment, irradiation is by UV light having wavelength ranging from about 250 nm to 400 nm, including all the values in the range for instance, 251 nm, 252 nm, 253 nm, 254 nm and so on and so forth. In an alternate embodiment, the irradiation is by visible light having wavelength ranging from about 400 nm to 750 nm, including all the values in the range, for instance, 401 nm, 402 nm, 403 nm, 404 nm and so on and so forth.

In some embodiments of the present disclosure, the detecting peroxide radical according to the above described method is carried out by colour appearance of the peroxide radical, wherein the colour of the peroxide radical is different from the colour of components apart from peroxide radical in the sample. That is, there is change in optical appearances of peroxide radical and other components in the sample.

In an embodiment, Figure 8 illustrates change in optical appearance of peroxide radical, such as benzoyl peroxide (BPO) and photochromic compound alone, following combinatorial exposure to photochromic compound and light having wavelength of about 365 nm (UV light).

The present disclosure further relates to method of separating popcorn polymer from the respective parent polymer in a sample suspected of having popcorn polymer.

In some embodiments of the present disclosure, the method of separating popcorn polymer in a sample suspected of having popcorn polymer from the respective parent polymer, comprises- exposing the sample to combination of light and photochromic compound, followed by separating the popcorn polymer from the respective parent polymer.

In some embodiment of the present disclosure, the photochromic compound is selected from a group comprising Spiropyran, Spirooxazine, Dithienylethene, dihydroazulene, indoline,naphthopyran, dihydropyrene, phenoxynaphthacenequinone, azobenzene, fulgimide, semicarbazones, bianthrone, phenylhydrazine, phenylosazone, and naphthalenone, 2,3,4,4-tetrachloronaphthalen-1-(4H)-one, azines, thioindigoides, dinitrobenzylpyridine, Fulgides, derivatives thereof or any combination thereof.

In some embodiments of the present disclosure, the photochromic compound is in an amount ranging from about 0.001 wt% to 10 wt%, including all the values in the range, for instance, 0.002 wt%, 0.003 wt%, 0.004 wt%, 0.005 wt% and so on and so forth.

In some embodiment of the present disclosure, the light is UV light having wavelength ranging from about 250 nm to 400 nm, including all the values in the range, for instance, 251 nm, 252 nm, 253 nm, 254 nm and so on and so forth.

In some embodiments of the present disclosure, the light is visible light having wavelength ranging from about 400 nm to 750 nm, including all the values in the range, for instance, 401 nm, 402 nm, 403 nm, 404 nm and so on and so forth.

In some embodiments of the present disclosure, the exposing described in the method comprises-
a) contacting the sample with the photochromic compound; and
b) irradiating the sample with light.

In some embodiments of the present disclosure, the contacting comprises- mixing the sample with about 0.001 wt% to 10 wt% of the photochromic compound. In an embodiment, the photochromic compound is present in any value within the range of about 0.001 wt% to 10 wt%, for instance, 0.001 wt%, 0.002 wt%, 0.003 wt%, 0.004 wt% and so on and so forth.

In an exemplary embodiment, the photochromic compound is dissolved in solvent prior to mixing with the sample to obtain solution of photochromic compound. In an embodiment, the solvent is selected from a group comprising, toluene, cyclohexane, tetrahydrofuran, chloroform, dichloromethane, hexane, benzene, chlorobenzene, dichlorobenzene, diethyl ether, ethyl acetate, acetone, and any combination thereof. In an embodiment, the photochromic compound in the solution is in an amount ranging from about 0.001 wt% to 10 wt%, including all the values in the range, for instance, 0.001 wt%, 0.002 wt%, 0.003 wt%, 0.004 wt% and so on and so forth.

In some embodiments of the present disclosure, irradiating the sample with the light is carried out for a duration ranging from about 1 second to 60 minutes. In an embodiment, the light is UV light having wavelength ranging from about 250 nm to 400 nm, including all the values in the range for instance, 251 nm, 252 nm, 253 nm, 254 nm and so on and so forth. In an alternate embodiment, the light is visible light having wavelength ranging from about 400 nm to 750 nm, including all the values in the range, for instance, 401 nm, 402 nm, 403 nm, 404 nm and so on and so forth.

In some embodiments of the present disclosure, the exposing comprises:
a) irradiating the sample with light;
b) contacting the sample with the photochromic compound; and
c) irradiating the sample with light again.

In some embodiments of the present disclosure, the irradiating in the step a) is carried out for a duration ranging from about 1 second to 60 minutes. In an embodiment, irradiation is by UV light having wavelength ranging from about 250 nm to 400 nm, including all the values in the range for instance, 251 nm, 252 nm, 253 nm, 254 nm and so on and so forth. In an alternate embodiment, the irradiation is by visible light having wavelength ranging from about 400 nm to 750 nm, including all the values in the range, for instance, 401 nm, 402 nm, 403 nm, 404 nm and so on and so forth.

In some embodiments of the present disclosure, the contacting in the step b) comprises mixing the sample with about 0.001 wt% to 10 wt% of the photochromic compound. In an embodiment, the photochromic compound is present in any value within the range of about 0.001 wt% to 10 wt%, for instance, 0.001 wt%, 0.002 wt%, 0.003 wt%, 0.004 wt% and so on and so forth.

In an exemplary embodiment, the photochromic compound is dissolved in solvent prior to mixing with the sample to obtain solution of photochromic compound. In an embodiment, the solvent is selected from a group comprising, toluene, cyclohexane tetrahydrofuran, chloroform, dichloromethane, hexane, benzene, chlorobenzene, dichlorobenzene, diethyl ether, ethyl acetate, acetone, and any combination thereof. In an embodiment, the photochromic compound in the solution in an amount ranging from about 0.001 wt% to 10 wt%, including all the values in the range, for instance, 0.001 wt%, 0.002 wt%, 0.003 wt%, 0.004 wt% and so on and so forth.

In some embodiments of the present disclosure, the irradiating in the step c) is carried out for a duration ranging from about 1 second to 60 minutes. In an embodiment, irradiation is by UV light having wavelength ranging from about 250 nm to 400 nm, including all the values in the range for instance, 251 nm, 252 nm, 253 nm, 254 nm and so on and so forth. In an alternate embodiment, the irradiation is by visible light having wavelength ranging from about 400 nm to 750 nm, including all the values in the range, for instance, 401 nm, 402 nm, 403 nm, 404 nm and so on and so forth.

In some embodiments of the present disclosure, separating the popcorn polymer according to the above described method is carried out by colour appearance of the popcorn polymer, wherein the colour of the popcorn polymer is different from the colour of the respective parent polymer in the sample. That is, there is change in optical appearances of popcorn polymer and respective parent polymer in the sample.

In an exemplary embodiment, the popcorn polymer appears pink in colour upon exposing the sample to combination of the light and the photochromic compound. In an exemplary embodiment, the parent polymer appears blue in colour upon exposing the sample to combination of the light and the photochromic compound. Thus, there is evident change in optical appearance of the popcorn polymer and parent polymer, enabling efficient separation of the popcorn polymer from the respective parent polymer according to the above described method.

In an embodiment, the popcorn polymer separated according to the method of the present disclosure includes but it is not limited to butadiene popcorn polymer, styrene butadiene popcorn polymer. Change in the optical appearance of the popcorn polymer from their respective parent polymer, such as polybutadiene and styrene butadiene rubber enable simple and efficient separation of the popcorn polymer.

In an embodiment of the present disclosure, the popcorn polymer is separated from their respective parent polymer by technique including but it is not limited to physical separation.

The inventors have identified that the radicals on the popcorn polymer reacts effectively with the zwitter ionic isomers of photochromic compounds in presence of light, such as UV light and/or visible light (sun light). Thus, there is change in the colour of the photochromic compound on the popcorn polymer. However, the parent polymer of the popcorn does not contain any radicals, as a result, the parent polymer takes up the colour of the photochromic compound in presence of light, such as UV light and/or visible light. Thus, there is change in the optical appearance of the popcorn polymer (pink in colour) and parent polymer (blue in colour, which is colour of the photochromic compound). This mechanism enables simple and efficient separation of the popcorn polymer from their respective parent polymer.

In an embodiment, the Figure 11 illustrates separation of styrene butadiene part (parent polymer) from the SBR popcorn polymer (pink) by physical separation technique. The separation of the popcorn polymer and the respective parent polymer was possible due to change in the optical appearance of the popcorn polymer and the respective parent polymer.

It is to be understood that the foregoing description is illustrative not a limitation. While considerable emphasis has been placed herein on 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. 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. Similarly, additional embodiments and features of the present disclosure will be apparent to one of ordinary skill in art based upon description provided herein.

The methods of the present disclosure provide following advantages:
- The method is simple and economical. No sophisticated instrument is required to carry out the method.
- The method is capable of detect small quantities (about 1 gm) of popcorn polymer from the sample.
- Minimum quantity of the photochromic compound solution is sufficient to carry out the method

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 may be practiced and to further enable those of skill in the art to practice the embodiments. Accordingly, following examples should not be construed as limiting the scope of the embodiments herein.

EXAMPLES

Example 1: Preparation of photochromic compound solution
About 0.5 gm of photochromic compound was dissolved in about 1 ml of AR grade toluene in an aluminium foil covered test tube to obtain the photochromic compound solution.

Example 2: Detection of butadiene popcorn polymer
A sample suspected of comprising butadiene popcorn polymer was mixed with about 2 drops (for 1 gm of sample) of spiropyran having concentration of about 0.5 mg/ml (in tetrahydrofuran), followed by exposing the sample to UV light having wavelength of about 365 nm, for a duration of 1 minute.
Figure 3 illustrates the change in the optical appearances of butadiene popcorn (pink colour) and polybutadiene polymer (parent polymer) (blue colour). The difference in the colour enabled simple and efficient detection of the butadiene popcorn polymer.
Example 3: Detection of butadiene popcorn polymer
A sample suspected of comprising butadiene popcorn polymer was exposed to UV light having wavelength of about 365 nm for a duration of about 1 minute, followed by mixing the sample with about 2 drops (for 1 gm of sample) spiropyran having concentration of about 0.5mg/ml (in tetrahydrofuran). Further, the sample was again exposed to UV light having wavelength of about 365 nm for a duration of about 1 minute.
Figure 4 illustrates the change in the optical appearances of butadiene popcorn (pink colour) and polybutadiene polymer (parent polymer) (blue colour). The difference in the colour enabled simple and efficient detection of the butadiene popcorn polymer.

Example 4: Detection of butadiene popcorn polymer
A sample suspected of comprising butadiene popcorn polymer was mixed with about 2 drops (for 1 gm of sample) of spiropyran having concentration of about 0.5 mg/ml (in tetrahydrofuran), followed by exposing the sample to visible light (full spectrum sunlight) for a duration of 5 minutes.
Figure 6 illustrates the change in the optical appearances of butadiene popcorn (pink colour) and polybutadiene polymer (parent polymer) (blue colour). The difference in the colour enabled simple and efficient detection of the butadiene popcorn polymer.

Example 5: Detection of butadiene popcorn polymer
A sample suspected of comprising butadiene popcorn polymer was mixed with about 2 drops (for 1 gm of sample) of spiropyran having concentration of about 3 mg/ml (in cyclohexane), followed by exposing the sample to visible light (full spectrum sunlight) for a duration of 5 minutes.
Figure 7 illustrates the change in the optical appearances of butadiene popcorn (pink colour) and polybutadiene polymer (parent polymer) (blue colour). The difference in the colour enabled simple and efficient detection of the butadiene popcorn polymer.

Example 6: Detection of benzoyl peroxide (BPO) radical
A sample suspected of comprising benzoyl peroxide (BPO) radical contacted with photochromic compound having concentration of about 0.5 mg/ml, followed by exposing the sample to UV light having wavelength of about 365 nm for a duration of about 1 minute. Change in the optical appearance of the BPO radical from other components in the sample enable detection of the BPO radical.
Figure 8 illustrates the colour change BPO radical upon combinatorial exposure to photochromic compound and light.

Example 7: Detection of butadiene popcorn polymer
A sample suspected of comprising butadiene popcorn polymer was mixed with about 2 drops (for 1 gm of sample) of spiropyran having concentration of about 0.5 mg/ml (in tetrahydrofuran), followed by exposing the sample to UV light having wavelength of about 395 nm to 400 nm, for a duration of 1 minute.
Figure 5 illustrates the change in the optical appearances of butadiene popcorn (pink colour) and polybutadiene polymer (parent polymer) (blue colour). The difference in the colour enabled simple and efficient detection of the butadiene popcorn polymer.

Example 7: Separation of styrene butadiene rubber (SBR) popcorn from respective styrene butadiene rubber (parent polymer)
A sample suspected of comprising SBR popcorn was mixed with about 2 drops (for 1 gm of sample) of spiropyran having concentration of about 0.5 mg/ml (in tetrahydrofuran), followed by exposing the sample to UV light having wavelength of about 365 nm, for a duration of 1 minute. Thereafter, SBR popcorn was separated from SBR by physical means.

Figure11 illustrates physical separation of styrene butadiene part (parent polymer) from the SBR popcorn polymer (pink) by physical separation technique. The separation of the popcorn polymer and the respective parent polymer was possible due to change in the optical appearance of the popcorn polymer and the respective parent polymer.

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.

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.

As regards the embodiments characterized in this specification, it is intended that each embodiment be read independently as well as in combination with another embodiment. For example, in case of an embodiment 1 reciting 3 alternatives A, B and C, an embodiment 2 reciting 3 alternatives D, E and F and an embodiment 3 reciting 3 alternatives G, H and I, it is to be understood that the specification unambiguously discloses embodiments corresponding to combinations A, D, G; A, D, H; A, D, I; A, E, G; A, E, H; A, E, I; A, F, G; A, F, H; A, F, I; B, D, G; B, D, H; B, D, I; B, E, G; B, E, H; B, E, I; B, F, G; B, F, H; B, F, I; C, D, G; C, D, H; C, D, I; C, E, G; C, E, H; C, E, I; C, F, G; C, F, H; C, F, I, unless specifically mentioned otherwise.

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.
, Claims:1. A method for detecting popcorn polymer or peroxide radical in a sample suspected of having popcorn polymer or peroxide radical, said method comprises-
exposing the sample to combination of light and photochromic compound to detect the popcorn polymer or peroxide radical in the sample.

2. The method as claimed in claim 1, wherein the exposing comprises:
a) contacting the sample with the photochromic compound; and
b) irradiating the sample with light having wavelength ranging from about 250 nm to 750 nm.

3. The method as claimed in claim 1, wherein the exposing comprises:
a) irradiating the sample with light having wavelength ranging from about 250 nm to 750 nm;
b) contacting the sample with the photochromic compound; and
c) irradiating the sample with light having wavelength ranging from about 250 nm to 750 nm.

4. The method as claimed in claim any one of claims 1 to 3, wherein the photochromic compound is selected from a group comprising Spiropyran, Spirooxazine, Dithienylethene, dihydroazulene, indoline,naphthopyran, dihydropyrene, phenoxynaphthacenequinone, azobenzene, fulgimide, semicarbazones, bianthrone, phenylhydrazine, phenylosazone, naphthalenone, 2,3,4,4-tetrachloronaphthalen-1-(4H)-one, azines and thioindigoides, dinitrobenzylpyridine, Fulgides and combination thereof.

5. The method as claimed in claim 2, wherein the photochromic compound is in an amount ranging from about 0.001 wt% to 10 wt%.

6. The method as claimed in claim 2, wherein the irradiating is carried out with UV light having wavelength ranging from about 250 nm to 400 nm or visible light having intensity ranging from about 400 nm to 750 nm.

7. The method as claimed in claim 2, wherein the irradiating is carried out for a duration ranging from about 1 second to 60 minutes.

8. The method as claimed in claim 3, wherein the irradiating in step a) is carried out with UV light having wavelength ranging from about 250 nm to 400 nm or with visible light having intensity ranging from about 400 nm to 750 nm.

9. The method as claimed in claim 3, wherein the irradiating in step c) is carried out with UV light having wavelength ranging from about 250 nm to 400 nm or with visible light having intensity ranging from about 400 nm to 750 nm.

10. The method as claimed in claim 3, wherein the irradiating in step a) is carried out for a duration ranging from about 1 second to 60 minutes.

11. The method as claimed in claim 3, wherein the irradiating in step c) is carried out for a duration ranging from about 1 second to 60 minutes.

12. The method as claimed in claim 3, wherein the photochromic compound is in an amount ranging from about 0.001 wt% to 10 wt%.

13. The method as claimed in claim 1, wherein the detecting is carried out by colour appearance of the popcorn polymer, wherein the colour of the popcorn polymer is different from the colour of non-popcorn polymer or parent polymer in the sample.

14. A method of separating popcorn polymer from parent polymer, said method comprises-
exposing sample suspected of having popcorn polymer to combination of light and photochromic compound, followed by separating the popcorn polymer from the parent polymer.

15. The method as claimed in claim 14, wherein the exposing comprises:
a) contacting the sample with the photochromic compound; and
b) irradiating the sample with light having wavelength ranging from about 250 nm to 750 nm.

16. The method as claimed in claim 14, wherein the exposing comprises:
a) irradiating the sample with light having wavelength ranging from about 250 nm to 750 nm;
b) contacting the sample with the photochromic compound; and
c) irradiating the sample with light having wavelength ranging from about 250 nm to 750 nm.

17. The method as claimed in any one of claims 14 to 16, wherein the photochromic compound selected from a group comprising spiropyran, spirooxazine and combination thereof.

18. The method as claimed in claim 15, wherein the photochromic compound is in an amount ranging from about 0.001 wt% to 10 wt%.

19. The method as claimed in claim 15, wherein the irradiating is carried out with UV light having wavelength ranging from about 250 nm to 400 nm or with visible light having wavelength ranging from about 400 nm to 750 nm.

20. The method as claimed in claim 15, wherein the irradiating is carried out for a duration ranging from about 1 second to 60 minutes.

21. The method as claimed in claim 16, wherein the irradiating in step a) is carried out with UV light having wavelength ranging from about 365 nm to 400 nm or with visible light having wavelength ranging from about 400 nm to 750 nm.

22. The method as claimed in claim 16, wherein the irradiating in step c) is carried out with UV light having wavelength ranging from about 365 nm to 400 nm or with visible light having wavelength ranging from about 400 nm to 750 nm.

23. The method as claimed in claim 16, wherein the irradiating in step a) is carried out for a duration ranging from about 1 second to 60 minutes.

24. The method as claimed in claim 16, wherein the irradiating in step c) is carried out for a duration ranging from about 1 second to 60 minutes.

25. The method as claimed in claim 16, wherein the photochromic compound is in an amount ranging from about 0.001 wt% to 10 wt%.

26. The method as claimed in claim 14, wherein the separating the popcorn polymer from the parent polymer is carried out based on distinct colour appearance of the popcorn polymer from the parent polymer.