About solid surface: 

From an installer's viewpoint solid surface is very similar to wood with regard to its ability to be cut and joined. Seams are virtually invisible which allows large expanses of countertop space to be connected with no visible joints. This nice feature also means that a solid surface sink can be joined to the countertop for a seamless installation, with no discernible edge between the countertop and the sink.

GENERAL :

Standard Type
Standard Type solid surface sheets are designed for horizontal, vertical, wet, and dry applications. Standard Type solid surface sheets do not require a full substrate to perform in horizontal applications.

Special Purpose Type
Special Purpose Type solid surface sheets are similar to Standard Type, however, the composition of the sheets may be altered to meet specific aesthetic requirements. This change in composition may affect the performance properties of the sheets. Special Purpose Type solid surface sheets may not be suitable for certain applications.

Veneer Type
Veneer Type solid surface sheets are similar to Standard or Special Purpose Type in composition. Due to their thickness, they must be laminated onto a substrate to perform in horizontal applications. Veneer Type solid surface sheets may not be suitable for certain applications.

What is the difference between acrylic and polyester?  
Acrylic and polyester solid surface have many similarities. Acrylic solid surface can be thermoformed to the most demanding radiuses, while polyesters cannot be shaped to as tight a radius. Both acrylic and polyester products will scorch if a hot item is placed on the surface. Both acrylic and polyester can achieve a matte, satin, and high polished finish. Polyester products polish more easily and have the ability to achieve a translucent appearance in a satin or high polish finish.

Material - It's Chemistry .......... the  Technical’s:

Solid surface is made up of two main constituents called a "filler" and a "binder". The filler in most cases is a substance known as "ATH" or Alumina Trihydrate. ATH is a natural mineral that's in the form of a white powder when used in the manufacture of solid surface.
This sometimes results in scratches that show up as white or light-colored lines, particularly in darker surfaces. The scratch accentuates the ATH used in the makeup of the surfacing material. ATH is also a natural fire-retardant which gives solid surface countertops good fire-resistance.
The binder that's used to hold the ATH and any other secondary ingredients together is a resin that's either pure acrylic or polyester or a combination of both. This is another important point because there are differences between the two materials. Each has its own characteristics that impact the look, fabrication and in some cases, the durability of the solid surface. 

Acrylic: 

Acrylic-based material was the first type of solid surface, formulated by the DuPont® company. Acrylic enjoys several advantages over polyester in that it's harder, more impact resistant and less brittle than polyester. It won't fade or discolor from exposure to ultraviolet light whereas polyester has less resistance to UV light. Acrylic also has greater thermo formability - meaning it can be formed and shaped with heat more easily than polyester. This is important during the fabrication of your countertops should your design incorporate any bends or other features that require the material to be formed.

Polyester:

Polyester on the other hand is more chemical resistant particularly with regard to acrylic-based chemicals such as acetone and nail polish remover. Polyester can also achieve a higher polish than acrylic and offers a greater ability for achieving a translucent effect. 
Beyond these main ingredients solid surface manufacturers include numerous additives aimed at enhancing various aspects of the material. Each has their own "recipe" based on various attributes they're trying to achieve.

What Do I Need To Know About It?

Fabrication - Who Installs it and How It's Installed is Important
Solid surface installation is not for the do-it-yourselfers, at least if you want a durable, long-lasting countertop. The fabrication and installation of solid surface countertops requires craftsmen that are trained in the skills necessary to install them. The process involves cutting, routing and bonding various pieces together to create the final product.

Positives and Negatives .......... important stuff:

Solid surface countertops look good and perform well but they're not perfect. These highs and lows are meant to offer some perspective but don't consider them as purely black and white. In some cases, one person's positive will be another's negative. It all depends on your view and expectations.

 The Positives: 

•Non-Porous - Resists stains and food-borne bacteria and doesn't require any sealing
•Durable - Impact resistant
•Renewable and Restorable - Scratches can be sanded out and more significant damage can be repaired with 'seamless' patches
•Long Lasting - Because it's renewable it can be maintained for a long period of time.
•Seamless Joints - Allows for expansive stretches of countertop without visible seams and integral sinks with no visible joints (other than the delineation between a sink and countertop of different colors).
•Waterproof - No worries about water damage in the proximity of sinks
•Wide Manufacturer Base - Numerous makers typically result in a wide color selection and price competitiveness
•Warm Feel - Doesn't feel as cold to the touch as stone, metal or tile
•Homogeneous - The color and pattern goes all the way through the material so that it maintains it's look even if it needs sanding or renewing

...And The Negatives:

•Not Tolerant to High Heat - Being a plastic, it's not immune to high heat sources or possible damage from the application of a hot pan
•Glossy Surfaces Limit Practicality - Glossy surfaces will tend to show scratches and dull more easily than matte or satin finishes and aren't very practical for high-use areas
•Susceptible to Scratches and Cuts - Plastic is obviously softer than metal, stone and tile and will need more care to avoid this type of wear and tear
•Requires Skilled Fabricators - Longevity, quality and sometimes warranty depend on the skills and qualifications of the fabricator installing the countertop

Brand Choices - Are They All The Same? ... are you brand conscious?

Since solid surface was first introduced by the DuPont® company numerous manufacturers have come on line with their own products. Each has their own unique formulation and method of manufacture but virtually all of them use the same primary ingredients of fillers and resin binders.

So you may ask, are they all the same? The problem with the answer to this question is that it's not that black-and-white. The best answer may lie with an analogy to something we're all familiar with, such as car brands.

Each auto manufacturer can make a car that operates satisfactorily, incorporates the necessary operational and safety features and can transport us where we want to go with reasonable reliability. The same is true about similar 'commodities' like solid surface countertops. The differences lie in the details and that's where being an educated buyer proves it's worth in sorting through all the choices.

So what makes them different? Consider the following:

Colors: 

The quantity of colors and patterns varies among manufacturers. Each brand will have their own different color categories and while there are similarities, there are differences as well. Some specialize in very unique colors not offered by other manufacturers. If you fall in love with one particular color or style that you can't find anywhere else you may end up choosing that brand over all the others, regardless of other considerations.

Cost:

Cost will vary somewhat among manufacturers and even between color and pattern selections within a particular brand selection. One key point to keep in mind is that if you have your mind set on one particular color but think it's too expensive you may be able to find the same or a very similar color or pattern at a lower price from a different manufacturer. There are similarities among the colors and patterns produced by the various manufacturers so it pays to shop around.

...do you want a modern kitchen countertop that doesn’t cost like a car? use Solid Surface