Key Advantages of Polycarbonate Windows

Modern polycarbonate has vastly superior impact strength than glass and will not shatter when exposed to high strains or blunt force. Crack resistance is especially valuable – representing just one of the many reasons polycarbonate is used in fighter jet canopies and windows. Polycarbonate windows can be coated to a hardness comparable to glass. Therefore, these windows resist scratching, and many chemicals commonly used to wash vehicles or clean glass.

Furthermore, laminated glass is also subject to delamination – where the bonding between layers fails – displaying unsightly patterns known as “traveling air pockets.” Aside from being aesthetically unpleasant, over time, these air pockets can seriously diminish visibility around the edges of the affected transparencies.

At less than half the weight of glass — (SG: 1.2 vs. 2.45) — polycarbonate is an excellent alternative, especially where weight plays a key factor in design. With current trends erring towards ever more efficient, environmentally conscious manufacturing processes for vehicles, designers are becoming ever more focused on shedding as much weight as possible to achieve greater performance and fuel efficiency.

Generally, flat unprocessed glass is less expensive to purchase than polycarbonate. However, the tempered glass used in most vehicles is about equivalent in cost. Nevertheless, formed and/or laminated glass will be far more costly to produce than modern polymers.

Above all, if a window is to have a more defined shape, with complex curvatures, the forming tools for glass are usually made from steel or ceramic and become very expensive.

By contrast, the tools used for forming polycarbonate windows are generally made of fiberglass-reinforced resin. As such, the difference in tooling costs can be substantial; a consideration that becomes far more important for low-volume production.

Although glass can be formed into curved shapes – due to its restrictive malleability – the finished shape will be quite limited, with complex shapes being far more challenging and costly to achieve.

By contrast, modern polycarbonate can be easily formed into far more radical compound shapes while retaining excellent optical properties and minimum aberration.

Polycarbonate transmits more light than glass; in fact, up to 90% of visible light. By contrast, mineral glass transmits between 80-90%, depending on the type of glass.

In cases where laminated glass has several layers, such as ballistic formulations, the image observed through the pane tends to adopt a greenish hue, whilst polycarbonate remains neutral.

The thermal conductivity of polycarbonate is considerably superior to laminated glass. This is advantageous for insulation, resulting in lower running costs for heating and air-conditioning.

Equally, Polycarbonate offers 99.99% UV blocking as compared to 25% for glass. Similarly, up to 40% of infra-red is blocked compared to 0% for glass, depending on the tint being used. This is especially important for equipment operating in a hot environment or under strong sunshine. Furthermore, these specialty grades also protect interior electronic components and upholstery from excessive heat and fading.

Although polycarbonate is softer by nature in its raw form, thanks to the many advances achieved with technology, and through the application of silicate coating, polycarbonate can achieve a hardness approaching that of glass.

The silicate coating affords far superior protection, thus resisting most scratches and making the transparencies impervious to yellowing and chemical attacks.