The present invention relates to recovery of polymers from laminated glass, in particular to a process for recovering polyvinyl butyral polymer(s) (PVB) from windshields.
BACKGROUND OF THE INVENTION
Laminated glass consists of two or more layers of glass, between them one or more layers of polyvinyl butyral (PVB) are sandwiched. Such that for laminated glass first-use polyvinyl butyral (PVB) is used for as the layer in between due to its excellent features: great adherence to glass, high impact strength, high flexibility, excellent optical clarity, high stability (especially against ultraviolet rays), thermal stability or insensitivity to moisture.
The windshield or windscreen of an aircraft, car, bus, motorbike or tram is the front window, which provides visibility whilst protecting occupants from the elements.
Modern windshields are generally made of laminated safety glass, a type of treated glass, which consists of, typically, two curved sheets of glass with a plastic layer laminated between them for safety, and bonded into the window frame.
Polyvinyl butyral (or PVB) is a resin mostly used for applications that require strong binding, optical clarity, adhesion to many surfaces, toughness and flexibility. It is prepared from polyvinyl alcohol by reaction with butyraldehyde. The major application is laminated safety glass for automobile windshields. The manufacture of polyvinyl butyral (PVB) is expensive, however with recycling process, a product with a high degree of added value and purity can be produced.

The above processes do not achieve a degree of purity high enough for the reuse thereof as polyvinyl butyral (PVB) sheets for manufacturing laminated glass.
Therefore, it is readily apparent that there is a need for a process for recovering polyvinyl butyral polymer(s) (PVB) by recycling windshields of automobiles.
OBJECTIVE OF THE INVENTION
The principal objective of the present invention is to overcome the disadvantages of the conventional processes.
An objective of the present invention is to provide a process for recovering polyvinyl butyral polymer(s) (PVB) by recycling laminated glass of automobiles, particularly cars.
Another objective of the present invention is to provide a process for recovering polyvinyl butyral polymer(s) (PVB), wherein the polymer so produced is employed for preparing car mats, red oxide paint/primer or as raw material in footwears, adhesive and other industry.
Another objective of the present invention is to provide a process for recovering polyvinyl butyral polymer(s) (PVB), wherein the windshields are either damaged or accidental windshield glasses of cars.
Yet another objective of the present invention is to provide a process that is simple in design and easy to implement.
The foregoing and other objects of the present invention will become readily apparent upon further review of the following detailed description of the preferred embodiment as illustrated in the accompanying drawings.

SUMMARY OF THE INVENTION
The present invention is directed to a process for recovering polyvinyl butyral polymer(s) (PVB) by recycling damaged laminated glass of cars.
According to an embodiment of the present invention, the process for manufacturing polyvinyl butyral polymer(s) (PVB) by recycling laminated glass of automobiles, comprises the steps of; crushing laminated glass to obtain a crushed laminated glass; moisturing/watering/humdification the crushed laminated glass by adding suitable chemical( such as a detergent powder) to form a humidified glass-polymer mixture; storing the humidified glass-polymer mixture under ambient moisture and temperature to maintain humidifying conditions; and separating the polymer from the laminated glass by treating the humidified glass-polymer mixture.
In another embodiment, about 90 to 93% of glass cullet and the polymer along with rubber bidding is obtained and the polymer is separated from the laminated glass by treating the humidified glass-polymer mixture in an extruder machine.
According to another embodiment of the present invention, the process for recovery of polyvinyl butyral (PVB) granules from a windshield glass, comprises the steps of ; crushing the windshield glass to obtain crushed windshield glass; humidifying the windshield glass to obtain humidified glass-PVB mixture; separating PVB from the humidified glass-PVB mixture; and pelletizing the PVB to produces PVB granules.
While the invention has been described and shown with particular reference to the preferred embodiment, it will be apparent that variations might be possible that would fall within the scope of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS
These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings where:
Figure 1A-1B illustrates flow of the process according to an embodiment herein.
DETAILED DESCRIPTION OF THE INVENTION
The following description includes the preferred best mode of one embodiment of the present invention. It will be clear from this description of the invention that the invention is not limited to these illustrated embodiments but that the invention also includes a variety of modifications and embodiments thereto. Therefore the present description should be seen as illustrative and not limiting. While the invention is susceptible to various modifications and alternative constructions, it should be understood, that there is no intention to limit the invention to the specific form disclosed, but, on the contrary, the invention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the invention as defined in the claims.
In any embodiment described herein, the open-ended terms "comprising," "comprises," and the like (which are synonymous with "including," "having" and "characterized by") may be replaced by the respective partially closed phrases "consisting essentially of," consists essentially of," and the like or the respective closed phrases "consisting of," "consists of, the like.
As used herein, the singular forms "a," "an," and "the" designate both the singular and the plural, unless expressly stated to designate the singular only.
The present invention is directed to a process for recovering polyvinyl butyral

polymer(s) (PVB) by recycling damaged laminated glass of cars.
The process for manufacturing polyvinyl butyral polymer(s) (PVB) by recycling laminated glass of automobiles, comprises the steps of; crushing (102) laminated glass to obtain a crushed laminated glass; moisturising/watering/humidifying (104) the crushed laminated glass by adding suitable chemical( such as a detergent powder) to form a humidified glass-polymer mixture; storing (106) the humidified glass-polymer mixture under ambient moisture and temperature to maintain humidifying conditions; and separating (108) the polymer from the laminated glass by treating the humidified glass-polymer mixture as illustrated in Figure 1A. In an embodiment, the humidified glass-polymer mixture is subjected to acidic conditions. In an embodiment, the pH of the acidic condition is preferable between 3 and 7. The remaining mixture, obtained after separation of glass from the humidified polymer-glass mix is then subjected to pelletising treatment or extrusion treatment or both. After the removal of glass contamination, the granules of the polymer may be made by adding any chemical or filler.
In an embodiment, the glass may be crushed manually using hammers or in a crushing machine. In an embodiment, the glass-polymer humidified mixture can be separated into its constituents manually or in a separator machine. In an embodiment, the moisturisation is done under acidic conditions. In an embodiment, a detergent or a buffer may be added while the crushed glass is subjected to humidifying or moisturising conditions.
In an embodiment, about 90 to 93% of glass cullet and the polymer along with rubber bidding is obtained and the polymer is separated from the laminated glass by treating the humidified glass-polymer mixture in an extruder machine. The polymer so obtained from the humidified glass-polymer mixture, may still contain contamination of glass particles.

The process for recovery of polyvinyl butyral (PVB) granules from a windshield glass, comprises the steps of ; crushing (110) the windshield glass to obtain crushed windshield glass; humidifying (112) the windshield glass to obtain humidified glass-PVB mixture; separating (114) PVB from the humidified glass-PVB mixture; and pelletizing (116) the PVB to produce PVB granules as illustrated in Figure IB. In an embodiment, the humidified PVB-glass mixture is subjected to acidic conditions to ease the coming off of PVB from the glass. In an embodiment, the pH of the acidic condition is preferable between 3 and 7. In an embodiment, the windshield may be crushed manually using hammers or in a crushing machine. In an embodiment, the glass-PVB humidified mixture can be separated into its constituents manually or in a separator machine.
The crushed glass is used to make glass sheets and other items.
The moisture level of the crushed winshield glass is maintained for 2 to 3 weeks or as per the time and temperature of the weather. In an embodiment, the process may be accelerated under hotter conditions.
The polyvinyl butyral polymer(s) (PVB) is employed for preparing car mats, red-oxide paint/primer and PVB compound for footwear, adhesive, paint and other industries.
The windshields used in the present invention are either damaged or accidental windshield glasses of cars.
While the disclosure has been presented with respect to certain specific embodiments, it will be appreciated that many modifications and changes may be made by those skilled in the art without departing from the spirit and scope of the disclosure. It is intended, therefore, by the appended claims to cover all such modifications and changes as fall within the true spirit and scope of the disclosure.

WE Claim :
1. A process for recovering a polymer from a laminated glass, comprising the
steps of;
crushing (102) laminated glass to obtain a crushed laminated glass;
moisturing/watering/humdifying (104) the crushed laminated glass by adding suitable chemical( such as a detergent powder) to form a humidified glass-polymer mixture;
storing (106) the humidified glass-polymer mixture under ambient moisture and temperature to maintain humidifying conditions; and
separating (108) the polymer from the laminated glass by treating the humidified glass-polymer mixture.
2. The process as claimed in claim 1, wherein the polymer is polyvinyl butyral.
3. The process as claimed in Claim 1, wherein about 90 to 93% of glass cullet and the polymer along with rubber bidding is obtained.
4. The process as claimed in claim 1, wherein the polymer is separated from the laminated glass by treating the humidified glass-polymer mixture in an extruder machine.
5. The process as claimed in claim 1, further comprising pelletizing the polymer to obtain polymeric granules.
6. A process for recovery of polyvinyl butyral (PVB) granules from a windshield glass, comprises the steps of;
crushing (110) the windshield glass to obtain crushed windshield glass;
humidifying (114) the windshield glass to obtain humidified glass-PVB mixture;
separating (116) PVB from the humidified glass-PVB mixture; and

pelletizing (118) the PVB to produces PVB granules.
7. The process as claimed in claim 1, wherein the PVB is separated from glass-PVB mixture in an extruder machine.
8. The process as claimed in Claim 1 or 4, wherein said PVB produced is employed further for preparing car mats, red oxide paint/primer, PVB Compound for footwear, adhesive, ink and other industries.
9. The process as claimed in Claim 1, wherein about 90 to 93% of glass cullet and the PVB along with rubber bidding is obtained.